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CHAPTER XI
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    Priestley as a man of science—His characteristics as a philosopher—Experiments and Observations on Different Kinds of Air—His discovery of the influence of vegetation on vitiated air—Atmospheric1 air not elementary—His researches on nitric oxide2—Eudiometry—Nitrous oxide—Discovers hydrogen chloride—Prepares oxygen from nitre (1771)—Isolates ammonia gas—Discovers sulphur dioxide—Dephlogisticated air (oxygen)—Discovers silicon4 fluoride—Intra-diffusion5 of gases—Respiration6—Priestley’s opinions of the value of experimental science in education—Discovers nitrosulphuric acid—Notes the constancy of composition of the atmosphere—Prepares chlorine—Sound in “air”—Experiments relating to phlogiston—The seeming conversion7 of water into air—Watt8 and the compound nature of water—Discovers sulphuretted hydrogen—Priestley’s confession9 of faith in phlogiston.

Priestley’s position in the history of science mainly rests on his discoveries in pneumatic chemistry. The course of inquiry10 which he began at Leeds was continued by him, with characteristic assiduity and conspicuous11 success, at Calne, and his labours added largely to the number of the aeriform bodies which were clearly recognised as distinct substances, essentially12 differing from each other, and not merely modifications14 of a common principle, modified or affected16 by properties more or less fortuitous and accidental. The old idea of the nature of “air” had its origin in the doctrine17 of the Four Elements. It is Priestley’s merit that he, more than any man of his time, contributed to the overthrow18 of this conception as the basis of a philosophical19 system of the constitution of the material universe. 168 Although Priestley could not be unmindful that his claim to scientific fame was to be found in the succession of volumes which he called Experiments and Observations on Different Kinds of Air, the very title suggests that he, at all events in the outset, was hardly conscious of the magnitude and true significance of his work. Priestley was in no real sense a speculative20 philosopher: he was indeed pre-eminently21 the type of man whom Hobbes disparaged23 as an “experimentarian philosopher,” and an experimentarian philosopher he remained to the end of his days. He was aware of his limitations, and many passages from his works, and especially from his correspondence, might be quoted in proof of this fact. His simple, unaffected candour was indeed one of the charms of his character and the secret of much of his influence. It is reflected in every page of his scientific writings. His own discoveries, taken collectively, did more than those of any one of his contemporaries to uproot26 and destroy the only generalisation by which his immediate27 predecessors28 had sought to group and connect the phenomena29 of chemistry, but he was wholly unable to perceive this fact. A patient and industrious30 observer, absolutely truthful31, and, as he hoped and believed, unbiassed and impartial33, he was nevertheless entirely34 lacking in the higher qualities of the imagination or in that power of divination35 which is the characteristic of men of the type of Newton. The contrast between Priestley—the social, political and theological reformer, always in advance of his times, receptive, fearless and insistent36; and Priestley the man of science—timorous and halting when he might well be bold, conservative and orthodox when almost every other active worker was heterodox and progressive—is most striking. And 169 yet, such is the irony37 of circumstance, Priestley’s name mainly lives as that of a chemical philosopher. When men have desired to do him honour, and have sought to perpetuate38 his memory by statues in public places, he is generally represented as making a chemical experiment. In reality, great as Priestley’s merit is as an experimentarian philosopher, his greater claim on our regard and esteem39 rests upon his struggles and his sufferings in the cause of civil, political and religious liberty.

The years which Priestley spent at Calne constitute the most fruitful period of his scientific career. Practically all that he did in the way of solid achievement and of addition to the armoury of science was effected during that time. Although, after leaving Lord Shelburne, he continued to pursue scientific inquiry with his wonted zeal40 and industry, doubtless adding thereby41 to his fame among his contemporaries, posterity42 has set the true measure of appreciation43 to his later efforts. He doubtless made many hundreds of experiments in connection with more or less well-defined trains of inquiry; nevertheless, it cannot be maintained that during his subsequent period he added many first-rate facts to our knowledge, or indeed discovered any facts at all comparable in importance with those he ascertained45 during his life in Wiltshire. On the contrary, what he did observe—as for example the seeming conversion of water into air—too frequently led him astray and was the cause of error to himself and others. Thus Watt’s claim to be considered as an independent, if not the first and true, discoverer of the real chemical nature of water is based upon Priestley’s experimental blunders. Watt was undoubtedly47 accurate in his surmise48, but the surmise was right in spite of, and 170 not by reason of, Priestley’s experimental evidence. Priestley recorded his experiments with such fulness that it is now easy to perceive where he went wrong. He was constantly on the verge49 of a discovery, sometimes indeed of a discovery of cardinal50 importance, but as constantly it eluded51 his grasp. The experiments on the seeming conversion of water into air might have led him, when he got over his chagrin52 on the detection of the real cause of his error, to the recognition of the underlying53 truth in it, namely, the principle of the diffusion of gases. He was, of course, familiar with the fact that the various gases he discovered, or which were known to him, differed in relative density54, and he knew perfectly55 well that they tended to escape from the bottles in which they were contained if these were uncovered and freely exposed to the air. But, so far as we can learn, he never seems to have pondered on these facts, or noted56 their connection with the phenomena he observed in the course of his many experiments with Wedgwood’s retorts, and of the interchange of the water vapour he introduced into them with the gases of the fire which heated them. And yet, had he perceived even a glimmer57 of the truth he had sufficient means at his disposal, and sufficient knowledge from his own work and that of his contemporaries, to make the great step which it was reserved to Graham to accomplish half a century later.

Whilst the chief importance of the Experiments and Observations on Different Kinds of Air is that it is Priestley’s magnum opus, to his biographer it has the additional interest of affording an insight into the personal character and intellectual attributes of its author. Few writers on scientific subjects have ever 171 taken their readers so completely into their confidence as Priestley. Whatever he knows or thinks he tells: doubts, perplexities, blunders are set down with the most refreshing58 candour; one forgives the prolixity59 and occasional tediousness, even the little touches of self-satisfaction, in view of the transparent61 honesty of purpose, the single-minded pursuit of truth for its own sake, wholly apart from preconception or bias32 of dogma which shine on every page. As key-notes to character, even the dedications62 and prefaces to the several volumes have their peculiar64 value and charm, as evidence of the workings of an ingenuous65 mind.

The publication of the six volumes comprising the original work—the edition of greatest value to Priestley’s biographer—extended from 1775 to 1786. Although the space at our disposal precludes66 any attempt at a full account of the contents, it is necessary to set these out in such detail as may serve to afford a just idea of their value, and with such comment as may be necessary to elucidate67 their significance.

In the preface to the first volume, which made its appearance in 1775, with a dedication63 to Lord Shelburne, Priestley thinks it necessary to explain why he has decided68, contrary to his original intention, but with the approbation69 of the President and of his friends in the Royal Society, not to send them any more papers on the subject of “Air” at present but to make immediate publication of all he has done with respect to it. In view, he says, of the rapid progress that has been made and may be expected to be made in this branch of knowledge, “unnecessary delays in the publication of experiments relating to it are peculiarly unjustifiable.”

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    “When, for the sake of a little more reputation, men can keep brooding over a new fact, in the discovery of which they might possibly have very little real merit, till they think they can astonish the world with a system as complete as it is new, and give mankind a prodigious71 idea of their judgment72 and penetration73, they are justly punished for their ingratitude74 to the fountain of all knowledge, and for the want of a genuine love of science and of mankind in finding their boasted discoveries anticipated and the field of honest fame pre-occupied by men who, from a natural ardour of mind, engage in philosophical pursuits, and with an ingenuous simplicity76 immediately communicate to others whatever occurs to them in their inquiries77.”

Priestley’s productions, from the very nature of the case make no pretensions78 to completeness.

    “In completing one discovery we never fail to get an imperfect knowledge of others of which we could have no idea before, so that we cannot solve one doubt without creating several new ones.”

He farther observes that a person who means to serve the cause of science effectually must hazard his own reputation so far as to risk even mistakes in things of less moment.

    “Among a multiplicity of new objects and new relations some will necessarily pass without sufficient attention; but if a man be not mistaken in the principal objects of his pursuits he has no occasion to distress79 himself about lesser80 things.

    “In the progress of his inquiries he will generally be able to rectify81 his own mistakes; or if little and envious82 souls should take a malignant83 pleasure in detecting them for him and endeavouring to expose him, he is not worthy84 of the name of a philosopher if he has not strength of mind sufficient to enable him not to be disturbed at it. He who does not foolishly affect to be above the failings of humanity will not be mortified85 when it is proved that he is but a man.”

He made it a rule to disclose the real views with which he made his experiments. Although, he says, 173 by following a contrary maxim86 he might have acquired a character of greater sagacity, he thought that two good ends were secured by his method—one as tending to make his narrative87 more interesting, and the other as encouraging other adventurers in experimental philosophy by showing them that by pursuing even false lights real and important truths may be discovered, and that in seeking one thing we often find another. He believes, however, that he writes more concisely88 than is usual with those who publish accounts of their experiments, and in thus refraining from swelling89 his book “to a pompous90 and respectable size” he trusts he will earn the gratitude75 of those philosophers who, having but little time to spare for reading, which is always the case with those who do much themselves, will thereby be kept not too long from their own pursuits. He then comments on what he justly considers the amazing improvements in natural knowledge which have been made within the century, and contrasts these with the comparative poverty as regards scientific results of the many preceding ages, which yet abounded92 with men who had no other object but study; and he rejoices to think that this rapid progress of knowledge, extending itself not this way or that way only, but in all directions, will be the means of extirpating93 all error and prejudice and of putting an end to all undue94 and usurped95 authority in the business of religion as well as of science.

    “It was ill policy in Leo the Tenth to patronise polite literature. He was cherishing an enemy in disguise. And the English hierarchy96 (if there be anything unsound in its constitution) has equal reason to tremble even at an air-pump or an electrical machine.”

He regrets that the rich and great in this country, unmindful 174 of the example of Bacon, give less attention to these matters than do men of rank and fortune in other countries: he contrasts the pleasure of the pursuit of science with the pains and penalties of the pursuit of politics.

    “If extensive and lasting97 fame be at all an object, literary, and especially scientifical, pursuits are preferable to political ones in a variety of respects.... If extensive usefulness be the object, science has the same advantage over politics. The greatest success in the latter seldom extends farther than one particular country and one particular age, whereas a successful pursuit of science makes a man the benefactor98 of all mankind and of every age. How trifling99 is the fame of any statesman that this country has ever produced to that of Lord Bacon, of Newton, or of Boyle; and how much greater are our obligations to such men as these than to any other in the whole Biographia Britannica.”

It would be interesting to know the sentiments of Lord Shelburne, then in the cold shade of retirement100, as he perused101 these passages, and whether he realised the truth of the little homily from his “tame philosopher.”

The preface is followed by an introduction, in which Priestley gives a rapid and confessedly imperfect survey of the state of knowledge concerning “air” prior to 1774. He gives to Boyle the credit of first clearly recognising that elastic102 fluids exist differing essentially from the air of the atmosphere, but agreeing with it in the properties of weight, elasticity103 and transparency. But he also points out that two remarkable104 kinds of factitious air had long been known to miners, viz., choke damp, which is heavier than air, which lies at the bottom of pits, extinguishes flame and kills animals; and the other, called fire damp, which is lighter105 than common air, is found, therefore, near the roofs of subterraneous 175 places and is liable to take fire and explode like gunpowder106. “The word damp signifies vapour or exhalation in the German and Saxon languages.”

    “Air of the former kind, besides having been discovered in various caverns107, particularly the Grotta del Cane108 in Italy, had also been observed on the surface of fermenting109 liquors, and had been called gas (which is the same with geist, or spirit) by Van Helmont and other German chemists; but afterwards it obtained the name of fixed110 air, especially after it had been discovered by Dr Black of Edinburgh to exist, in a fixed state, in alkaline salts, chalk, and other calcareous substances.”

Black’s work is dealt with in half a dozen lines, and a passing reference is made to Macbride and Brownrigg. A very imperfect account is given of the work of Hales, although it is stated that “his experiments are so numerous and various that they are justly esteemed111 to be the solid foundation of all our knowledge of this subject.” This section concludes with the mention of Cavendish’s determinations of the relative weights of fixed air (carbon dioxide), and inflammable air from metals (hydrogen), and of Lane’s observations that water charged with carbonic acid will dissolve iron, “and thereby become a strong chalybeate.”

Priestley was the last man in the world to seek to disparage24 the work of his predecessors or to minimise what was due to them. In reality he had the intention, as he distinctly states, to write at his leisure the history and present state of discoveries relating to air, in a manner similar to his History of Electricity, and of the Discoveries Relating to Vision, Light and Colours, when no doubt he would have done full justice to all concerned. In the meantime he gives only such particulars as are necessary, in his judgment, to the understanding of his own work.

The remaining section of the introduction deals with 176 his method of experimenting and with the apparatus113 he employed. It is of historical interest as containing a description of that most useful article of chemical furniture, his well-known pneumatic trough. He explains its use and gives details of his modes of manipulation. What an advance these were in simplicity, ingenuity114 and convenience can only be fully115 realised by comparing his methods with those of Hales. Not the least of Priestley’s services to science were the improvements he effected in that section of operative chemistry which is concerned with the preparation, collection and storage of gaseous116 substances.

The main body of the volume is divided into two parts—the first dealing117 with observations made in and before 1772, the second with observations made in the year 1773 and in the beginning of 1774. In the outset Priestley finds himself at a disadvantage in regard to the only terms at that time in vogue118 for the factitious airs, viz., fixed, mephitic and inflammable, which, he rightly says, are not sufficiently119 characteristic and distinct. Strictly120 speaking, any two of these terms might be applied121 to any one of the “airs” then known. The inflammable air from metals, as well as choke damp, is noxious122, and therefore mephitic, as is fixed air, and since the inflammable airs are, apparently123, capable of being imbibed125 by certain substances they may equally be considered fixable. The term fixed air had, however, acquired a distinctive126 meaning, and rather than introduce a new term or change the signification of an old one, he would, with his contemporaries, restrict the term to the air which had been made the subject of Black’s memorable127 investigation128. The first paper in this section deals with fixed air; it is practically a reprint of that in the 177 Phil. Trans. and which has already been described in sufficient detail. In the course of his experiments he says he once thought that the readiest method of procuring129 fixed air, and in sufficient purity, would be to heat pounded lime-stone in a gun barrel, “making it pass through the stem of a tobacco pipe or a glass tube carefully luted to the orifice of it.”

    “In this manner I found that air is produced in great plenty; but, upon examining it, I found to my great surprise that little more than one half of it was fixed air, capable of being absorbed by water; and that the rest was inflammable, sometimes very weakly, but sometimes pretty highly so.”

He surmised130 that this “air” must come from the iron, and yet, he noted, it differed from the ordinary inflammable air from iron by the remarkable blue colour of its flame, and he concludes that “this inflammable principle may come from some remains131 of the animals from which it is thought that all calcareous matter proceeds.” Priestley, we now know, had incidentally converted some of the fixed air into the only other oxide of carbon, but he failed to appreciate the significance of his observation, and the credit of the discovery of carbon monoxide belongs to Cruikshank.

In his next paper on “Air in which Candles have burned,” Priestley made a discovery of the very highest importance. He had attempted to verify without success the allegation by the Count de Saluce, made in the memoirs133 of the Philosophical Society of Turin, that air vitiated by the combustion134 of candles could be restored by exposure to cold.

    “Though this experiment failed,” he says, “I have been so happy as by accident to have hit upon a method of restoring air which has been injured by the burning of candles, and to 178 have discovered at least one of the restoratives which Nature employs for this purpose. It is vegetation. This restoration of vitiated air, I conjecture135, is effected by plants imbibing136 the phlogistic matter with which it is overloaded137 by the burning of inflammable bodies. But whether there be any foundation for this conjecture or not, the fact is, I think, indisputable.”

He then proceeds to give an account of his observations on the growing of plants in confined air which led to his discovery.

    “One might have imagined,” he says, “that since common air is necessary to vegetable as well as to animal life, both plants and animals had affected it in the same manner; and I own I had that expectation when I first put a sprig of mint into a glass jar standing112 inverted138 in a vessel139 of water: but when it had continued there for some months I found the air would neither extinguish the candle, nor was it at all inconvenient140 to a mouse, which I put into it.... Finding that candles would burn very well in air in which plants had grown a long time, and having had some reason to think that there was something attending vegetation which restored air that had been injured by respiration, I thought it was possible that the same process might also restore the air that had been injured by the burning of candles.

    “Accordingly, on the 17th of August 1771, I put a sprig of mint into a quantity of air in which a wax candle had burned out, and found that on the 27th of the same month another candle burned perfectly well in it. This experiment I repeated, without the least variation in the event, not less than eight or ten times in the remainder of the summer.

    “Several times I divided the quantity of air in which the candle had burned out into two parts, and putting the plant into one of them left the other in the same exposure, contained also in a glass vessel immersed in water, but without any plant, and never failed to find that a candle would burn in the former but not in the latter.... This remarkable effect does not depend upon anything peculiar to mint, which was the plant that I always made use of till July 1772; for on the 16th of that month I found a quantity of this kind of air 179 to be perfectly restored by sprigs of balm, which had grown in it from the 7th of the same month.

    “That this restoration of air was not owing to any aromatic141 effluvia of these two plants not only appeared by the essential oil of mint having no sensible effect of this kind, but from the equally complete restoration of this vitiated air by the plant called groundsel, which is usually ranked among the weeds and has an offensive smell. Besides, the plant which I have found to be the most effectual of any that I have tried for this purpose is spinach142, which is of quick growth, but will seldom thrive long in water.”

The next paper on “Inflammable Air” is of slight importance, and indeed is full of errors. Priestley made no distinction between the inflammable air obtained by the action of acids on metals (hydrogen) and that formed by the destructive distillation143 of coal and other organic substances (marsh gas or carbonic oxide, or mixtures of the two), and his inability to distinguish these different gases accounts for many of the phenomena he observed and which he confesses himself unable to explain. The most sagacious observation in the memoir132 has reference to the colour of the electric spark in the different gases which he accurately144 describes.

The paper on “Air Infected with Animal Respiration or Putrefection” may be considered as the complement145 of that on “Air in which a Candle has burned out,” and is no less valuable.

    “That candles will burn only a certain time in a given quantity of air is a fact not better known than it is that animals can live only a certain time in it; but the cause of the death of the animal is not better known than that of the extinction146 of flame in the same circumstances; and when once any quantity of air has been rendered noxious by animals breathing in it as long as they could, I do not know that any methods have been discovered of rendering147 it fit for breathing again. It is evident, however, that there must be some 180 provision in Nature for this purpose, as well as for that of rendering the air fit for sustaining flame; for without it the whole mass of the atmosphere would, in time, become unfit for the purpose of animal life; and yet there is no reason to think that it is, at present, at all less fit for respiration than it has ever been. I flatter myself, however, that I have hit upon two of the methods employed by Nature for this great purpose. How many others there may be I cannot tell.”

One of these methods he eventually finds to be, as in the first case, the action of vegetation, and he proves by a number of decisive experiments

    “that plants, instead of affecting the air in the same manner with animal respiration, reverse the effects of breathing and tend to keep the atmosphere sweet and wholesome148 when it is become noxious in consequence of animals either living and breathing, or dying and putrefying in it.”

The other method he conceived to be the action of water, since he found that by vigorous agitation149 with water, air which breathing had rendered noxious could again be breathed for a further period.

    “I do not think it improbable but that the agitation of the sea and large lakes may be of some use for the purification of the atmosphere, and the putrid150 matter contained in water may be imbibed by aquatic151 plants, or be deposited in some other manner.”

When a confined volume of common air is placed in contact with a mixture of iron filings and sulphur made into a paste with water, a certain portion of the air is imbibed by the paste. This fact was first observed by Hales. Priestley repeated the observation and found that about a fifth or rather more of the volume of the air was thus absorbed. He noted that the residual152 “air” was rather lighter than common air, it had no action on lime-water and was exceedingly noxious to animals, by which is meant that it could not 181 be breathed by them. Priestley had thus prepared nitrogen, but he failed to recognise the individuality of this gas.

In his Statical Essays Hales makes mention of an experiment in which common air and air generated from pyrites by spirit of nitre made a turbid153 red mixture, and in which part of the common air was absorbed. This phenomenon “particularly struck” Priestley, who, acting154 upon Cavendish’s hint that the red appearance was probably dependent “upon the spirit of nitre only” and that the metals might answer as well as pyrites, proceeded to investigate the action of nitric acid upon a number of the metals, and as the result of his inquiries he succeeded in isolating155 the gas we now know as nitric oxide, but which he termed nitrous air.

    “Though,” he says, “I cannot say that I altogether like the term, neither myself nor any of my friends, to whom I have applied for the purpose, have been able to hit upon a better.”

This paper exhibits Priestley at his best. In it he describes all the main properties of nitric oxide.

    “One of the most conspicuous properties of this kind of air,” he says, “is the great diminution156 of any quantity of common air with which it is mixed, attended with a turbid red, or deep orange colour, and a considerable heat.... The diminution of a mixture of this and common air is not an equal diminution of both the kinds, which is all that Dr Hales could observe, but of about one fifth of the common air, and as much of the nitrous air as is necessary to produce that effect; which, as I have found by many trials, is about one half as much as the original quantity of common air.

    “I hardly know any experiment that is more adapted to amaze and surprise than this is, which exhibits a quantity of air which, as it were, devours157 a quantity of another kind of air half as large as itself, and yet is so far from gaining any 182 addition to its bulk that it is considerably158 diminished by it....

    “It is exceedingly remarkable that this effervescence and diminution, occasioned by the mixture of nitrous air, is peculiar to common air, or air fit for respiration, and, as far as I can judge from a great number of observations, is at least very nearly, if not exactly, in proportion to its fitness for this purpose; so that by this means the goodness of air may be distinguished159 much more accurately than it can be done by putting mice or any other animals to breathe in it.

    “This was a most agreeable discovery to me, as I hope it may be a useful one to the public; especially as from this time I had no occasion for so large a stock of mice as I had been used to keep for the purpose of these experiments.”

Priestley here suggests the basis of a method of Eudiometry, or method of measuring the goodness of air, which in his hands, but more especially in those of Cavendish, led to most important results. The quantitative160 analysis of the air may be said to have taken its rise from the publication of Priestley’s paper.

In the course of subsequent work on nitrous air Priestley had occasion to study its action on iron, whereby he says:—

    “A most remarkable and most unexpected change was made in the nitrous air,” the iron “makes it not only to admit a candle to burn in it, but enables it to burn with an enlarged flame.... Sometimes I have perceived the flame of the candle, in these circumstances, to be twice as large as it is naturally, and sometimes not less than five or six times larger; and yet without anything like an explosion, as in the firing of the weakest inflammable air.”

Priestley in this manner obtained nitrous oxide, the properties of which he subsequently studied in some detail.

In the paper which follows, viz., “On Air infected with the Fumes161 of Burning Charcoal162,” he incidentally gains 183 further insight into the nature of atmospheric air. By what he called throwing the focus of a burning mirror on charcoal suspended in air contained in a glass tube standing over water or mercury—a favourite method of his when he had occasion to heat a substance in a gas—he could observe the phenomena with great precision. He noticed the formation of the fixed air and determined163 the degree of diminution when the burning took place over water or over lime-water.

    “In this manner,” he says, “I diminished a given quantity of air one-fifth. Air thus diminished by the fumes of burning charcoal not only extinguishes flame, but is in the highest degree noxious to animals; it makes no effervescence with nitrous air, and is incapable164 of being diminished any farther by the fumes of more charcoal.... All my observations show that air which has once been fully diminished ... is not only incapable of any further diminution ... but that it has likewise acquired new properties, most remarkably165 different from those which it had before....”

By heating pieces of lead and tin in air by means of a burning glass he observed the formation of a metallic166 calx, the volume of air was diminished, and it also “was in the highest degree noxious and made no effervescence with nitrous air.”

The real significance of these phenomena was, however, wholly unperceived by Priestley, and phlogiston, as usual, led him astray. He had, of course, in all these experiments prepared nitrogen, and in a state of sensible purity. He imagined, however, that he had simply “phlogisticated” the air, the phlogiston coming from the charcoal and the metals, and that this phlogisticated air was imbibed by the water.

An experiment described by Cavendish led Priestley to study the action of “Spirit of Salt” (hydrochloric acid) 184 upon copper167. As Cavendish had already stated, the gas so evolved “lost its electricity by coming into contact with water.” By collecting the gas over mercury Priestley was able to study its properties more exactly. From certain anomalies in the experiments he says:—

    “I concluded that this subtle air did not arise from the copper, but from the spirit of salt; and presently making the experiment with the acid only, without any copper, or metal of any kind, this air was immediately produced in as great plenty as before; so that this remarkable kind of air is, in fact, nothing more than the vapour, or fumes of spirit of salt, which appear to be of such a nature that they are not liable to be condensed by cold, like the vapour of water and other fluids, and therefore may be very properly called an acid air, or more restrictively the marine169 acid air.”

The new gas discovered by Priestley we now call hydrogen chloride. Ordinary hydrochloric acid is simply an aqueous solution of it.

    “Water impregnated with it makes the strongest spirit of salt that I have seen, dissolving iron with the most rapidity.... Iron filings, being admitted to this air, were dissolved by it pretty fast, half of the air disappearing and the other half becoming inflammable air, not absorbed by water. Putting chalk to it, fixed air was produced.”

He subsequently found that the marine acid air was more conveniently made by the action of oil of vitriol upon common salt.

From the “miscellaneous observations” with which this section of the volume concludes, there can be little doubt that Priestley, without knowing it, had prepared oxygen gas from nitre as far back as 1771. The accounts he gives of the behaviour of the gas obtained by heating nitre in a gun-barrel plainly indicate this fact.

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    “A candle,” he says, “not only burned but the flame was increased, and something was heard like a hissing170 similar to the decrepitation of nitre in an open fire.” He also noted the effect of nitrous air upon it and concludes that “this series of facts relating to air extracted from nitre appear to me to be very extraordinary and important, and in able hands may lead to considerable discoveries.”

The second section of the volume deals with experiments and observations made in 1773 and the beginning of 1774, and opens with an account of the discovery of ammonia gas.

    “After I had made the discovery of the marine acid air, which the vapour of spirit of salt may properly enough be called ... it occurred to me that by a process similar to that by which this acid air is expelled from the spirit of salt an alkaline air might be expelled from substances containing volatile171 alkali.

    “Accordingly I procured172 some volatile spirit of sal ammoniac, and having put it into a thin phial, and heated it with the flame of a candle, I presently found that a great quantity of vapour was discharged from it; and being received in a vessel of quicksilver, standing in a basin of quicksilver, it continued in the form of a transparent and permanent air, not at all condensed by cold; so that I had the same opportunity of making experiments upon it as I had before on the acid air, being in the same favourable174 circumstances.... Wanting, however, to procure173 this air in greater quantities, and this method being rather expensive, it occurred to me that alkaline air might probably be procured, with the most ease and convenience, from the original materials, mixed in the same proportions that chemists had found by experience to answer the best for the production of the volatile spirit of sal ammoniac. Accordingly I mixed one-fourth of pounded sal ammoniac with three-fourths of slaked175 lime; and filling a phial with the mixture, I presently found it completely answered my purpose. The heat of a candle expelled from this mixture a prodigious quantity of alkaline air; and the same materials ... would serve me a considerable time without changing....”

186

He next studied the properties of the alkaline air. He found, of course, it was readily soluble176 in water.

    “Having satisfied myself with respect to the relation that alkaline air bears to water, I was impatient to find what would be the consequence of mixing this new air with the other kinds with which I was acquainted before, and especially with acid air; having a notion that these two airs, being of opposite natures, might compose a neutral air, and perhaps the very same thing with common air. But the moment that these two kinds of air came into contact a beautiful white cloud was formed, and presently filled the whole vessel in which they were contained.... When the cloud was subsided177 there appeared to be formed a solid white salt, which was found to be the common sal ammoniac, or the marine acid united to the volatile alkali....

    “Fixed air admitted to alkaline air formed oblong and slender crystals.... These crystals must be the same thing with the volatile alkalis which chemists get in a solid form by the distillation of sal ammoniac with fixed alkaline salts....

    “Alkaline air, I was surprised to find, is slightly inflammable....

    “That alkaline air is lighter than acid air is evident from the appearances that attend the mixture, which are indeed very beautiful. When acid air is introduced into a vessel containing alkaline air, the white cloud which they form appears at the bottom only and ascends178 gradually. But when the alkaline air is put to the acid the whole becomes immediately cloudy quite to the top of the vessel.”

Up to now Priestley had mainly confined himself to the narration179 of the new facts which he had discovered, barely mentioning any hypotheses that occurred to him.

    “The reason why I was so much upon my guard in this respect was lest, in consequence of attaching myself to any hypothesis too soon, the success of my future inquiries might be obstructed180. But subsequent experiments having thrown great light upon the preceding ones, and having confirmed the few conjectures181 I then advanced, I may now venture to speak of my hypotheses with a little less diffidence. Still, however, 187 I shall be ready to relinquish182 any notions I may now entertain if new facts should hereafter appear not to favour them.”

In a paper on “Common Air Diminished and made Noxious by Various Processes” he attempts to apply the current doctrine of phlogiston to account for the various phenomena he has observed, and with what success may be inferred from his conclusion

    “that in the precipitation of lime by breathing into lime-water, the fixed air, which incorporates with lime, comes not from the lungs but from the common air, decomposed183 by the phlogiston exhaled184 from them, and discharged, after having been taken in with the aliment, and having performed its function in the animal system.”

Priestley’s attempts at theorising brought little satisfaction to him or to his readers. Indeed he says:—

    “I begin to be apprehensive185 lest, after being considered as a dry experimenter, I should pass into the opposite character of a visionary theorist.... In extenuation186 of my offence let it, however, be considered that theory and experiments necessarily go hand-in-hand, every process being intended to ascertain44 some particular hypothesis, which, in fact, is only a conjecture concerning the circumstances or the cause of some natural operation; consequently that the boldest and most original experimenters are those who, giving free scope to their imaginations, admit the combination of the most distant ideas; and that though many of these associations of ideas will be wild and chimerical187, yet that others will have the chance of giving rise to the greatest and most capital discoveries, such as very cautious, timid, sober and slow-thinking people would never have come at.

    “Sir Isaac Newton himself, notwithstanding the great advantage which he derived188 from a habit of patient thinking, indulged bold and eccentric thoughts, of which his queries189 at the end of his book of Optics are a sufficient evidence. And a quick conception of distant analogies, which is the great key to unlock the secrets of Nature, is by no means incompatible190 188 with the spirit of perseverance191 in investigations192 calculated to ascertain and pursue those analogies.”

After this apologia, Priestley gives the reins193 to his imagination, or rather he allows phlogiston to drive the halting, ambling194 thing for him, with the result that he utterly195 loses his way and is eventually landed into an impassable quagmire196. It is not too much to say that not one of the “Queries, Speculations198 and Hints” with which the volume closes has stood the test of time.

The second volume, which made its appearance towards the end of 1775, is dedicated199 to Sir John Pringle, at that time President of the Royal Society. It opens, as usual, with a somewhat prolix60 but characteristic preface. But to his biographer Priestley’s prefaces are not the least interesting or valuable of his literary productions.

    “In a preface,” he says, “authors have always claimed a right of saying whatever they pleased concerning themselves, and not to lose this right it must now and then be exercised.”

In this respect Priestley has championed the prerogatives200 of authors for all time. This particular preface begins with an expression of self-laudation for the little delay the writer made in putting the first volume to the press.

    “In consequence of this considerable discoveries have been made by people of distant nations; and this branch of science, of which nothing, in a manner, was known till very lately, indeed now bids fair to be farther advanced than any other in the whole compass of natural philosophy.... And it will not now be thought very assuming to say that by working in a tub of water or a basin of quicksilver we may perhaps discover principles of more extensive influence than even that of gravity itself, the discovery of which, in its full extent, contributed so much to immortalise the name of Newton.

    189

    “Having been the means of bringing so many champions into the field, I shall, with peculiar pleasure, attend to all their achievements, in order to prepare myself, as I promised in the preface to my last volume, for writing the history of the campaign.”

After a delightfully201 na?ve compliment to his own ability as an accumulator of facts, and to his merits as an “instrument in the hands of Divine Providence202 ... concerning which I threw out some further hints in my former preface, which the excellent French translator was not permitted to insert in his version,” he advances this testimony203 to his impartiality204 as an historian:—

    “I even think that I may flatter myself so much, if it be any flattery, as to say that there is not, in the whole compass of philosophical writing, a history of experiments so truly ingenuous as mine, and especially the section on the discovery of dephlogisticated air, which I will venture to exhibit as a model of the kind. I am not conscious to myself of having concealed205 the least hint that was suggested to me by any person whatever, any kind of assistance that has been given me, or any views or hypotheses by which the experiments were directed, whether they were verified by the result or not.”

There is much else in the preface that might be quoted as illustrative of the character and mental attributes of its author. Priestley, the natural philosopher, never forgot that he was a minister of religion, and that to him theology was the greatest and most important of all the sciences, and he cannot forbear even, in what he intended to be a scientific disquisition on purely206 natural phenomena, from inculcating his belief in the divine origin of Christianity and his opinion concerning the doctrine of purgatory207 and the worship of the dead.

The first chapter is concerned with the discovery of what its author called Vitriolic208 Acid Air, but which we now know as sulphur dioxide.
190

Priestley imagined that as the liquid marine acid—that is hydrochloric acid—readily yielded an “air” on heating it might be that vitriolic acid, or oil of vitriol, would also afford a characteristic “air” when treated in a similar manner. Acting upon a suggestion of Mr Lane he heated oil of vitriol with olive oil, when he readily obtained a new species of air, which he collected over mercury as he “had been used to do it with the marine acid air; and the whole process was as pleasing and as elegant.” Priestley at once surmised that the olive oil worked by transferring its phlogiston to the vitriolic acid, and he naturally concluded that any substance rich in phlogiston would bring about the same result. He next tried charcoal.

    “I put some bits of charcoal into my phial instead of the oil or other inflammable matter which I had used before, and applying the flame of a candle I presently found that the vitriolic acid air was produced as well as in the former process, and in several respects more conveniently, the production of air being equable, whereby the disagreeable effect of a sudden explosion is avoided.... Finding that a great variety of substances containing phlogiston enabled the oil of vitriol to throw out a permanent acid air, I had some suspicion that mere13 heat might do the same, but I did not find that there was any foundation for that suspicion.... But though I got no air from the oil of vitriol by this process, air was produced at the same time in a manner that I little expected, and I paid pretty dearly for the discovery it occasioned. Despairing to get any air from the longer application of my candles, I withdrew them, but before I could disengage the phial from the vessel of quicksilver a little of it passed through the tube into the hot acid, when instantly it was all filled with dense168 white fumes, a prodigious quantity of air was generated, the tube through which it was transmitted was broken into many pieces, and part of the hot acid being spilled upon my hand burned it terribly, so that the effect of it is visible to this day. The inside of the phial was coated 191 with a white saline substance, and the smell that issued from it was extremely suffocating209.

    “This accident taught me what I am surprised I should not have suspected before, viz., that some metals will part with their phlogiston to hot oil of vitriol, and thereby convert it into a permanent elastic air, producing the very same effect with oil, charcoal, or any other inflammable substance.

    “Not discouraged by the disagreeable accident above mentioned, the next day I put a little quicksilver into the phial with the ground stopple and tube, along with the oil of vitriol, when, long before it was boiling hot, air issued plentifully210 from it, and being received in a vessel of quicksilver appeared to be genuine vitriolic acid air, exactly like that which I had procured before, being readily imbibed by water and extinguishing a candle in the same manner as the other had done....

    “After this I repeated the experiment with several other metals.... Copper treated in the same manner yielded air very freely, with about the same degree of heat that quicksilver had required, and the air continued to be generated with very little application of more heat.”

The theory apart, this paper is as important as these on ammonia and the marine acid air, and exhibits Priestley at his best. The observations he makes concerning the main properties of the new gas and its solubility211 in water, its inability to burn and to support flame, its heaviness, its power to unite with ammonia, to be absorbed by charcoal and to liquefy camphor, are all accurate.

    “Having hit upon a method of exhibiting some of the acids in the form of air, nothing could be easier than to extend this process to the rest.”

Accordingly he attempted to procure what he called the vegetable acid air by heating “exceedingly strong concentrated acid of vinegar,” and states that he succeeded in obtaining an air which extinguished the flame of a candle and was soluble in water. The paper 192 is very short and is full of contradictions. In reality, as he subsequently found, he was dealing with vinegar largely adulterated with oil of vitriol. The “vegetable acid air” had no real existence.

The next paper in the series is the most important of the whole, and the one of all others that has contributed most largely to Priestley’s reputation. It is entitled “Of Dephlogisticated Air, and of the Constitution of the Atmosphere,” and deals with the discovery of oxygen. It begins in the following characteristic fashion:—

    “The contents of this section will furnish a very striking illustration of the truth of a remark which I have more than once made in my philosophical writings, and which can hardly be too often repeated, as it tends greatly to encourage philosophical investigations, viz., that more is owing to what we call chance—that is, philosophically212 speaking, to the observation of events arising from unknown causes than to any proper design or preconceived theory in this business. This does not appear in the works of those who write synthetically213 upon these subjects, but would, I doubt not, appear very strikingly in those who are the most celebrated214 for their philosophical acumen215 did they write analytically216 and ingenuously217.

    “For my own part, I will frankly218 acknowledge that at the commencement of the experiments recited in this section I was so far from having formed any hypothesis that led to the discoveries I made in pursuing them that they would have appeared very improbable to me had I been told of them; and when the decisive facts did at length obtrude219 themselves upon my notice it was very slowly, and with great hesitation220, that I yielded to the evidence of my senses. And yet, when I reconsider the matter, and compare my last discoveries relating to the constitution of the atmosphere with the first, I see the closest and the easiest connection in the world between them, so as to wonder that I should not have been led immediately from the one to the other. That this was not the case I attribute to the force of prejudice which, unknown to ourselves, biases221 not only our 193 judgments222, properly so called, but even the perceptions of our senses; for we may take a maxim so strongly for granted that the plainest evidence of sense will not entirely change, and often hardly modify, our persuasions223; and the more ingenious a man is, the more effectually he is entangled224 in his errors, his ingenuity only helping225 him to deceive himself by evading226 the force of truth.”

He then points out that there are few maxims227 in philosophy that have laid firmer hold upon the mind than that air, meaning atmospherical228 air ... is a simple elementary substance, indestructible and unalterable, at least as much so as water was supposed to be. Priestley, in the course of his inquiries, was soon satisfied that atmospherical air was not an unalterable thing; that bodies burning in it, and animals breathing it and various other chemical processes, so far alter and deprive it as to render it altogether unfit for the purposes to which it is subservient229; and he had discovered methods, particularly the process of vegetation, which tended to restore it to its original purity.

    “But,” he says, “I own I had no idea of the possibility of going any further in this way and thereby procuring air purer than the best common air.”

As this paper is one of the classics of chemistry, as well as the chief corner-stone in the monument which Priestley erected230 to himself, it is necessary to examine it, as well as certain other papers which grew immediately out of it, in some degree of detail.

After a reference to a hypothesis of the origin and constitution of the atmosphere which occurs among the “Queries, Speculations and Hints” above referred to, and which is on a par3 with much in Priestley’s speculations, he proceeds to relate the circumstances which more immediately led to the most important of all his discoveries. 194 It was the accident of possessing a burning lens of “considerable force,” for want of which he could not possibly make many of the experiments that he had projected.

    “But having afterwards procured a lens of twelve inches diameter and twenty inches focal distance, I proceeded with great alacrity231 to examine, by the help of it, what kind of air a great variety of substances, natural and factitious, would yield, putting them into vessels232 [short, wide, round-bottomed phials], which I filled with quicksilver and kept inverted in a basin of the same. Mr Warltire, a good chemist, and lecturer in Natural Philosophy, happening to be at that time in Calne, I explained my views to him, and was furnished by him with many substances, which I could not otherwise have procured.

    “With this apparatus, after a variety of other experiments, an account of which will be found in its proper place on the 1st August 1774, I endeavoured to extract air from mercurius calcinatus per se;[17] and I presently found that, by means of this lens, air was expelled from it very readily. Having got about three or four times as much as the bulk of my materials, I admitted water to it, and found that it was not imbibed by it. But what surprised me more than I can well express was that a candle burned in this air with a remarkably vigorous flame, very much like that enlarged flame with which a candle burns in nitrous air exposed to iron or liver of sulphur,[18] but as I had got nothing like this remarkable appearance from any kind of air besides this particular modification15 of nitrous air, and I knew no nitrous acid was used in the preparation of mercurius calcinatus, I was utterly at a loss how to account for it.

    “In this case also, though I did not give sufficient attention to the circumstance at that time, the flame of the candle, besides being larger, burned with more splendour and heat than in that species of nitrous air; and a piece of red-hot wood sparkled in it, exactly like paper dipped in a solution of nitre, and it consumed very fast; an experiment which I had never thought of trying with nitrous air.
    195

    “At the same time that I made the above-mentioned experiment I extracted a quantity of air with the very same property from the common red precipitate233[19] which, being produced by a solution of mercury in spirit of nitre (nitric acid), made me conclude that this peculiar property, being similar to that of the modification of nitrous air above mentioned, depended upon something being communicated to it by the nitrous acid; and since the mercurius calcinatus is produced by exposing mercury to a certain degree of heat, where common air has access to it, I likewise concluded that this substance had collected something of nitre, in that state of heat, from the atmosphere.

    “This, however, appearing to me much more extraordinary than it ought to have done, I entertained some suspicion that the mercurius calcinatus on which I had made my experiments, being bought at a common apothecary’s, might, in fact, be nothing more than red precipitate; though, had I been anything of a practical chemist, I could not have entertained any such suspicion. However, mentioning this suspicion to Mr Warltire, he furnished me with some that he had kept for a specimen234 of the preparation, and which, he told me, he could warrant to be genuine. This being treated in the same manner as the former, only by a longer continuance of heat, I extracted much more air from it than from the other.

    “This experiment might have satisfied any moderate sceptic; but, however, being at Paris in the October following, and knowing that there were several very eminent22 chemists in that place, I did not omit the opportunity, by means of my friend Mr Magellan, to get an ounce of mercurius calcinatus prepared by Mr Cadet, of the genuineness of which there could not possibly be any suspicion; and at the same time I frequently mentioned my surprise at the kind of air which I had got from this preparation to Mr Lavoisier, Mr le Roy, and several other philosophers, who honoured me with their notice in that city, and who, I daresay, cannot fail to recollect235 the circumstance.”

This last remark is significant in reference to a claim which was subsequently put forward that the real 196 discoverer of oxygen was Lavoisier, and that he obtained it by heating mercuric oxide.[20]

Priestley also obtained the same air from red lead, which, he says,

    “confirmed me more in my suspicion that the mercurius calcinatus must get the property of yielding this kind of air from the atmosphere, the process by which that preparation and this of red lead is made being similar. As I never make the least secret of anything that I observe, I mentioned this experiment also, as well as those with the mercurius calcinatus and the red precipitate, to all my philosophical acquaintance at Paris and elsewhere, having no idea, at that time, to what these remarkable facts would lead.” [Nitrous oxide.]

Priestley, on his return to England, made an experiment with Cadet’s preparation, which he found to behave precisely236 like that he had procured from Warltire. He observed that the new gas was only sparingly soluble in water and that its power of causing a candle to burn with a strong flame was in nowise diminished by agitation with water—facts which he said convinced him

    “that there must be a very material difference between the constitution of the air from mercurius calcinatus and that of phlogisticated nitrous air, [nitrous oxide] notwithstanding their resemblance in some particulars.”

It was not, however, until the following March (1775) (he having meanwhile been intent upon his experiments on the vitriolic air [sulphur dioxide]), that he ascertained the real nature of the new air, and was led “though very gradually ... to the complete discovery of the constitution of the air we breathe.” By trials with the nitrous air and with mice he found that the new gas was eminently fit for respiration: nitrous air 197 reduced its volume to a greater extent than in the case of common air, and a mouse lived longer in it than it would in the same volume of common air.

    “Thinking of this extraordinary fact upon my pillow, the next morning I put another measure of nitrous air to the same mixture, and to my utter astonishment237 found that it was farther diminished to almost one-half of its original quantity.”

Priestley now utterly missed his way for a time. He sought to get the new air from the various oxides of lead, but the fetish of phlogiston again led him wrong, and eventually by a train of reasoning which is fully set forth238 in the paper, but which need not here be repeated, there remained, he says, no doubt in his mind

    “but that atmospherical air, or the thing that we breathe, consists of the nitrous acid and earth, with so much phlogiston as is necessary to its elasticity; and likewise so much more as is required to bring it from its state of perfect purity to the mean condition in which we find it.”

Priestley’s “complete discovery of the constitution of the air we breathe” was thus wholly erroneous: he was very far indeed from having a clear conception of its real nature.

Priestley’s description of the main properties of oxygen is however accurate, and lecturers in chemistry are indebted to him for some striking experimental illustrations of them.

    “I easily conjectured239,” he says, “that inflammable air would explode with more violence and a louder report by the help of dephlogisticated than of common air; but the effect far exceeded my expectations, and it has never failed to surprise every person before whom I have made the experiment.... The dipping of a lighted candle into a jar filled with dephlogisticated air is alone a very beautiful experiment. The strength and vivacity240 of the flame is striking, and the heat 198 produced by the flame in these circumstances is also remarkably great.... Nothing would be easier than to augment241 the force of fire to a prodigious degree by blowing it with dephlogisticated air instead of common air.... Possibly platina might be melted by means of it.

    “From the greater strength and vivacity of the flame of a candle, in this pure air, it may be conjectured that it might be peculiarly salutary to the lungs in certain morbid242 cases.... But perhaps we may also infer from these experiments that though pure dephlogisticated air might be very useful as a medicine, it might not be so proper for us in the usual healthy state of the body: for, as a candle burns out much faster in dephlogisticated than in common air, so we might, as may be said, live out too fast, and the animal powers be too soon exhausted243 in this pure kind of air. A moralist, at least, may say that the air which Nature has provided for us is as good as we deserve.... Who can tell but that, in time, this pure air may become a fashionable article in luxury. Hitherto only two mice and myself have had the privilege of breathing it.”

An experiment which Priestley says “I had the pleasure to see at Paris, in the laboratory of Mr Lavoisier, my excellent fellow-labourer in these inquiries, and to whom, in a variety of respects, the philosophical part of the world has very great obligations,” led him into a train of inquiry upon the action of nitric acid upon a wide range of organic substances, from which however no general results followed, in spite of much experimenting. He had at one time the idea that a fundamental difference existed in the behaviour of animal and vegetable matter with respect to nitric acid, but the observations were contradictory244, and although it is readily possible to interpret the phenomena in the light of our present knowledge, they led Priestley to no definite conclusions.

Of more importance is the work on the “Fluor Acid Air”—a substance discovered by “Mr Scheele, a Swede; 199 from which circumstance the acid is often distinguished by the name of the Swedish acid.” Priestley sought to make the air by heating Derbyshire spar (fluor spar) with oil of vitriol in glass vessels,

    “as in the process of making spirit of nitre from saltpetre; and the most remarkable facts that have been observed concerning it are, that the vessels in which the distillation is made are apt to be corroded245; so that holes will be made quite through them; and that when there is water in the recipient246, the surface of it will be covered with a crust of a friable247 stony248 matter.”

What Priestley actually produced by this method of experimenting was more or less pure silicon fluoride, which he proceeded to collect, in his usual fashion, over quicksilver.

    “I had no sooner produced this new kind of air but I was eager to see the effect it would have on water, and to produce the stony crust formed by their union, as described by Mr Scheele; and I was not disappointed in my expectations. The moment the water came into contact with this air the surface of it became white and opaque249 by a stony film.... Few philosophical experiments exhibit a more pleasing appearance than this, which can only be made by first producing the air confined by quicksilver, and then admitting a large body of water to it. Most persons to whom I have shown the experiment have been exceedingly struck with it.... The union of this acid air and water may also be exhibited in another manner, which to some persons makes a still more striking experiment, viz., by admitting the air, as fast as it is generated, to a large body of water resting on quicksilver.... It is, then, very pleasing to observe that the moment any bubble of air, after passing through the quicksilver, reaches the water, it is instantly, as it were, converted into a stone; but continuing hollow for a short space of time, generally rises to the top of the water.... I have met with few persons who are soon weary of looking at it; and some could sit by it almost a whole hour, and be agreeably amused all the time.”

200

Priestley’s attempts to explain the real nature of the fluor acid air were, as may be expected, not very happy.

    “These appearances I explain by supposing that the vitriolic acid, in uniting with the spar, is in part volatilised by means of some phlogiston contained in it, so as to form a vitriolic acid air; and there is also combined with this air a portion of the solid earthy part of the spar, which continues in a state of solution till, coming into contact with the water, the fluid unites with the acid, and the earth is precipitated250.”

The third volume of the work was published in the early part of 1777, with a dedication to Lord Stanhope. It opens, as usual, with the characteristically discursive251 preface, extending to thirty pages, in which the author apologises for the character of much in the volume. He is constrained252 to admit that numerous as his facts are, “few of them will appear so brilliant in the eye of the general scholar” as in either of the two former volumes, although he trusts they will “be thought no less valuable by philosophers and chemists.” Priestley, it would seem, was conscious that he was beginning, as the phrase goes, “to write himself out.”

    “Lest my readers should be alarmed at this addition of one volume after another on the same subject, I do assure them that I shall now certainly give them and myself some respite253, and deliver the torch to anyone who may be disposed to carry it, foreseeing that my attention will be sufficiently engaged by speculations of a very different nature.... It will be a great satisfaction to me, after the part that I have taken in this business, to be a spectator of its future progress, when I see the work in so many and so good hands, and everything in so rapid and so promising254 a way.

    “On taking leave of this subject I would entreat255 the candour and indulgence of my readers for any oversights256 they may discover in me as a philosopher, or imperfections as a writer. I am far from pretending to infallibility; but I have the satisfaction to reflect that, imperfect as my works may be found 201 to be, they are each as perfect as I was able to make them....

    “Upon this, as upon other occasions, I can only repeat that it is not my opinions on which I would be understood to lay any stress. Let the new facts, from which I deduce them, be considered as my discoveries, and let other persons draw better inferences from them if they can. This is a new and a wide field of experiment and speculation197, and a premature257 attachment258 to hypothesis is the greatest obstruction259 we are likely to meet with in our progress through it; and as I think I have been pretty much upon my guard myself, I would caution others to be upon their guard too.”

These passages evidently were written under the influence of the feeling of resentment260 with which he viewed the criticism to which his speculations were subjected abroad. Fontana, Lavoisier and others were, indeed, zealously261 engaged in using Priestley’s own facts to destroy the conception by which he explained them. An appeal to the balance was felt to be necessary, and Priestley, as a logician262, could not resist it. But he was no quantitative chemist: the habits of a Cavendish were quite foreign to his genius: patient, scrupulous263 attention to numerical accuracy was not one of his characteristics: he was one of the most industrious of experimenters—delighting, indeed, in manipulation for the mere sake of it, but withal hasty and superficial. It is nowhere evident in his writings that his problems were attacked according to any carefully-thought-out plan. He confesses indeed, on more than one occasion, he tested the inflammability of one of his numerous “airs” because he had a lighted candle near him: had the candle not been lighted it would not have occurred to him to do it. Priestley was, in fact, a pioneer: he showed the existence of a new world for science, and he 202 himself roamed over a portion of it, like a second Joshua; but he had not the experience or the aptitude264 to accurately map out even that fraction.

There is little in the third volume of permanent value. It is largely an account of a series of disconnected observations on the action of nitric acid upon a variety of substances, which, however, led to no general conclusions. It is, however, certain that if Priestley could have induced himself to follow up certain of his observations he would have arrived at facts of far greater importance than those he actually narrates265. “Speculation,” he said, by way of rejoinder to Lavoisier, “is a cheap commodity. New and important facts are most wanted, and therefore of most value,” and the new and important facts were within his grasp if he had only reached out for them.

Another portion of the work is concerned with supplementary266 observations on the gases treated of in the preceding volumes, partly by way of correction and partly additional. Here and there we have a suggestive passage, as in the paper on “Experiments on the Mixture of Different Kinds of Air that have no Mutual267 Action,” in which he thus clearly indicates the principle of the intra-diffusion of gases.

    “The result of my trials has been this general conclusion: that when two kinds of air have been mixed it is not possible to separate them again by any method of decanting268 or pouring them off, though the greatest possible care be taken in doing it. They may not properly incorporate, so as to form a third species of air, possessed269 of new properties; but they will remain equally diffused270 through the mass of each other; and whether it be the upper or the lower part of the air that is taken out of the vessel, without disturbing the rest, it will contain an equal mixture of them both.”

203

Another suggestive paper is on “Respiration and the Use of the Blood,” which was read to the Royal Society on January 25, 1776, and appears in the Phil. Trans., vol. lxvi. Priestley, of course, regarded respiration as a phlogistic process, and “that the use of the lungs is to carry off a putrid effluvium, or to discharge that phlogiston, which had been taken into the system with the aliment, and has become, as it were, effete271, the air that is respired serving as a menstruum for that purpose.” This he thinks he has “proved to be effected by means of the blood, in consequence of its coming so nearly into contact with the air in the lungs, the blood appearing to be a fluid wonderfully formed to imbibe124 and part with that principle which the chemists call phlogiston, and changing its colour in consequence of being charged with it or being freed from it.” The facts in this paper are for the most part correctly stated, but the discoverer of oxygen led the world woefully astray as to the part played by that gas in the phenomena of respiration.

The fourth volume made its appearance in March 1779, with a dedication to Sir George Savile, who had rendered Priestley the service of introducing him and his invention of soda-water to the notice of the Admiralty. In the preface, which is commendably272 short, he makes some reference to the respite which he had promised himself and his readers, but trusts, by way of extenuation, “it may be sufficient to allege273 the instability of human purposes and pursuits.” He had intended to devote himself to metaphysics.

    “But that kind of writing,” he says, “is a thing of a very different nature from this. I can truly say ... that single sections in this work have cost me more than whole volumes of the 204 other; so great is the difference between writing from the head only and writing, as it may be called, from the hands.”

The fact was Priestley could not keep away from his laboratory.

    “Having acquired a fondness for experiments, even slighter inducements than I have had would have been sufficient to determine my conduct.”

The preface is noteworthy for its plea for the position of experimental science in the scheme of general education.

    “If we wish to lay a good foundation for a philosophical taste, and philosophical pursuits, persons should be accustomed to the sight of experiments and processes in early life. They should, more especially, be early initiated274 in the theory and practice of investigation, by which many of the old discoveries may be made to be really their own; on which account they will be much more valued by them. And, in a great variety of articles, very young persons may be made so far acquainted with everything necessary to be previously275 known as to engage (which they will do with peculiar alacrity) in pursuits truly original.”

In the course of some observations on the effect “of impregnating oil of vitriol with nitrous acid vapour” he discovered nitrosulphuric acid, the so-called “Leaden Chamber276 Crystals,” whose properties and behaviour with water he describes with accuracy and even eloquence277. Of these crystals he says: “A more beautiful appearance can hardly be imagined, and I am afraid I shall never see the like again.” He also noticed the formation of the dark brown compound which nitric oxide forms with a solution of green vitriol, and adds:—

    “To determine whether the phenomena attending the impregnation of the solution of green vitriol with nitrous air depended in any measure upon the seeming astringency278 of that solution ... I impregnated a quantity of green tea, which is also 205 said to be astringent279, with nitrous air, but no sensible change of colour was produced in it.”

He several times noticed the deep blue liquid which nitrogen peroxide forms with cold water. He made many attempts to use nitric oxide as an antiseptic, especially for culinary purposes. But the gastronomic280 results with fowls281 and pigeons were not to his liking282, although he says, “my friend Mr Magellan ... had not so bad an opinion of this piece of cookery as I had.” One cannot read Priestley’s description of his multifarious experiments without being struck with the number of occasions in which he just missed making discoveries of first-rate importance. It is obvious that he had obtained chlorine without recognising it, even before the news of Scheele’s discovery reached this country. He had also prepared, without knowing it, phosphoretted hydrogen and phosphorous acid. At times, however, he can follow a clue with remarkable perspicacity283; as in his observation of the cause of the “flouring” of mercury, and in his discovery of a method of removing lead and tin from that metal.

The subject of “dephlogisticated air” naturally continued to interest him, and he again returns to it in this volume, for he says:—

    “As it sometimes amuses myself it may perhaps amuse others to look back with me to the several steps in the actual progress of this investigation, some of which I overlooked in my last account of it.”

He points out, as already stated, that he must have had the new gas in his hands as far back as November 1771, having obtained it from nitre. He admits that he had no particular view in making his crucial experiment of August 1, 1774,

    “excepting that of extracting air from a variety of substances 206 by means of a burning lens in quicksilver, which was then a new process with me, and which I was very fond of.”

He explains how he was led to his speculation that “this kind of air, and consequently of atmospherical air, which is the same thing but in a state of inferior purity,” consists “of earth and spirit of nitre.”

    “But,” he adds, “I have since seen reason to suspect that hypothesis, plausible284 as it appears. Indeed, some of my late experiments would lead me to conclude that there is no acid at all in pure air.”

He then experiments with manganese, which Scheele, who independently discovered oxygen, had already employed, and finds that it yields the new air both when heated alone or with oil of vitriol. The production of oxygen from manganese was contrary to his expectations as the substances he had hitherto used, the precipitate per se and the red lead and the nitre, had all been subjected to “the influence of the atmosphere,” whereas “here was pure air from a substance which for anything that appeared had always been in the bowels285 of the earth, and never had had any communication with the external air.” This led to the surmise that possibly the expulsion of dephlogisticated air from such mineral substances

    “might assist in sustaining subterraneous fires.... The solution of the phenomena of subterraneous fires would certainly be much easier on the supposition of their supplying their own pabulum, by means of dephlogisticated air contained in substances exposed to their heat. I therefore desired Mr Landriani, who being in Italy had a good opportunity of making inquiries on the subject, to inform me whether any of those substances, and particularly manganese be found in their volcanoes; and his answer makes it rather probable that those fires are, in part, sustained by this means.”

The ease with which nitre parts with its oxygen on 207 heating furnished Priestley with the true explanation of its so-called “detonation286,” “concerning which,” he says, “the most improbable conjectures have been advanced by the most eminent philosophers and chemists.” After a reference to the hypothesis of Macquer, who assumes that what he calls “a nitrous sulphur” is produced, Priestley points out that

    “the doctrine of dephlogisticated air supplies the easiest solution imaginable of this very difficult phenomenon. Let any person but attend to the phenomena of the detonation of charcoal in nitre, and that of dipping a piece of hot charcoal into a jar of dephlogisticated air, and I think it will be impossible for him not to conclude that the appearances are the very same and must have the same cause.”

Of all the quantitative exercises performed by Priestley, by far the most numerous depended upon his application of nitric oxide to measure the “goodness” of air.

    “When,” he says, “I first discovered the property of nitrous air as a test of the wholesomeness287 of common air, I flattered myself that it might be of considerable practical use, and particularly that the air of distant places and countries might be brought and examined together with great ease and satisfaction; but I own that hitherto I have rather been disappointed in my expectations from it.... I gave several of my friends the trouble to send me air from distant places, especially from manufacturing towns, and the worst they could find to be actually breathed by the manufacturers, such as is known to be exceedingly offensive to those who visit them; but when I examined those specimens288 of air in Wiltshire, the difference between them and the very best air in this county, which is esteemed to be very good, as also the difference between them and specimens of the best air in the counties in which these manufacturing towns are situated289, was very trifling.... I have frequently taken the open air in the most exposed places in this country at different times of the year, and in different states of the weather, etc., but never found the difference so great as the 208 inaccuracy arising from the method of making the trial might easily amount to or exceed.”

Other observers, less careful or more sanguine290 than Priestley, were, however, successful in detecting the differences which prejudice led them to anticipate. Thus Signor Marsilio Landriani of Milan, whose name has already been mentioned in connection with the theory of subterraneous fires, in the course of a tour through Italy had the satisfaction of convincing himself

    “that the air of all those places, which from the long experience of the inhabitants has been reputed unwholesome, is found to be so to a very great degree of exactness by the eudiometer.... The air of the Pontine lakes, that of the Sciroccho at Rome (so very unwholesome), that of the Campagna Romana, of the Grotto291 del Cane, of the Zolfatara at Naples, of the baths of Nero at Baja, of the seacoast of Tuscany, were all examined by me and found to be in such a state as daily experience led me to expect.”

Modern eudiometry, making use of methods of far greater precision than were possible to Priestley, has confirmed his supposition that atmospheric air is remarkably constant in composition, and that its wholesomeness depends upon other causes than the relative amount of the dephlogisticated air contained in it.

Perhaps the most important of the many papers contained in this volume are those which relate to the “Melioration of Air by the Growth of Plants,” a subject to which Priestley gave attention, even whilst at Leeds, in 1771. In these papers he clearly proves that this “melioration” is connected with the green matter of leaves and that it is dependent upon sunlight. This observation is of fundamental importance and attracted much attention.

In the fifth volume, which was published in the 209 spring of 1781, with a dedication to Dr Heberden, when Priestley had moved to Birmingham, he again returns to this subject. Practically all the experimental work to which it relates was done whilst he was with Lord Shelburne, and mainly at Calne. During the former parts of the summer of 1780 he suffered from an illness which greatly interfered292 with his work, although he thinks that during his incapacity for making experiments his “hints for the farther prosecution293 of them are greatly accumulated.” It cannot be said that the five papers on the relations of vegetation to air, with which the volume opens, added very materially to the fundamental fact which Priestley had discovered. They furnished, however, additional evidence of it and no doubt stimulated294 further inquiry. If his facts could not be controverted295, his explanations and surmises296 were at least open to attack, and a number of observers, both here and abroad, busied themselves with the problems of physiological297 botany thereby suggested.

As regards the subject of “air” in general, although a large number of isolated298 observations are recorded in somewhat tedious detail, no new fact of first-rate importance is apparent. The experiments are largely supplementary to those in the preceding volumes and are for the most explanatory or corroborative299 of them. Perhaps the most important are those dealing with “the production of nitrous air in which a candle will burn,” by which is signified the gas we now know as nitrous oxide, but which Priestley eventually termed dephlogisticated nitrous air. The process he employed is no longer used in the production of this gas, but it sufficed in his hands to determine its individuality without doubt.
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Priestley’s methods of experiment with his various “airs” were very uniform. He tried their solubility in water, their power of supporting or extinguishing flame, whether they were respirable, how they behaved with acid and alkaline air, and with nitric oxide and inflammable air, and lastly how they were affected by the electric spark. He occasionally made attempts to weigh them, but his determinations of their relative density were altogether untrustworthy. Indeed, it is evident from the terms in which he speaks of these efforts that he was conscious of their inadequacy300. The result of submitting alkaline air (ammonia) to the electric spark, whereby it is resolved into nitrogen and hydrogen, surprised him not a little.

    “There are few experiments the rationale of which I less pretend to understand than the production of genuine and permanent inflammable air from alkaline air by means of the electric spark.... One query301 on this subject is, whence comes the phlogiston, which is certainly a principal ingredient in the constitution of inflammable air. Alkaline air, indeed, contains phlogiston, because in the manner in which I have generally produced it, it is itself partially302 inflammable; but it is not nearly so much so as the inflammable air which is produced by means of it. Besides, it will appear by the following experiments that the quantity of the inflammable air far exceeds that of the alkaline.”

Although Priestley clearly recognised the production of the inflammable air, “in no respect to be distinguished from that which is extracted from metals by acids,” and inferred it must come from the alkaline air (“the production having its limits”), he failed to detect the other constituent303 of ammonia. His determination of the actual increase in volume was inaccurate304, and his attempt to explain the phenomenon wholly fallacious.
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At the instigation of Mr Woulfe, whose name mainly lives in connection with a useful piece of chemical apparatus, Priestley was encouraged to hope that he would

    “find something remarkable in the solution of manganese in spirit of salt. Mr Woulfe, however, in a very friendly manner, at the same time, cautioned me with respect of the vapour that would issue from it, as from his own experience he apprehended305 it was of a very dangerous nature.... I cannot say that it was the apprehension306 of danger, but rather having other things in view, that prevented my giving much attention to the subject.”

Priestley’s experiments led to no decisive result: he of course recognised the

    “peculiar smell, exactly resembling that which is procured by dissolving red lead in the same acids.... On the application of heat it was easy to perceive that air, or vapour, was expelled; but it was instantly seized by the quicksilver.... This is a new field that is yet before me.”

Priestley never occupied that field. It is tolerably certain that both Woulfe and he had unknowingly prepared chlorine gas, but the glory of its discovery belongs to Scheele.

The paper “Of Sound in Different Kinds of Air” is worth quoting as showing Priestley at his best:—

    “Almost all the experiments that have hitherto been made relating to sound have been made in common air, of which it is known to be a vibration307, though it is likewise known to be capable of being transmitted by other substances. There could be little doubt, however, of the possibility of sound originating in any other kind of air, as well as being transmitted by them; but the trial had not been actually made, and I had an easy opportunity of making it.

    “Besides, the experiments promised to ascertain whether the intensity308 of sound was affected by any other property of the air in which it was made than the mere density of it. For 212 the different kinds of air in which I was able to make the same sound, besides differing in specific gravity, have likewise other remarkable chemical differences, the influence of which with respect to sound would, at the same time, be submitted to examination.

    “Being provided with a piece of clock-work, in which was a bell, and a hammer to strike upon it (which I could cover with a receiver, and which, when it was properly covered up, I could set in motion by the pressure of a brass309 rod going through a collar of leather), I placed it on some soft paper on a transfer. Then taking a receiver, the top of which was closed with a plate of brass, through which the brass rod and collar of leathers was inserted, I placed the whole on the plate of an air-pump, and exhausted the receiver of all the air that it contained. Then removing this exhausted receiver, containing the piece of clock-work, I filled it with some of those kinds of air that are capable of being confined by water.... Then by forcing down the brass rod through the collar of leathers I made the hammer strike the bell, which it would do more than a dozen times after each pressure. And the instrument was contrived310 to do the same thing many times successively after being once wound up.

    “Everything being thus prepared, I had nothing to do, after filling the same receiver with each of the kinds of air in its turn, but receding91 from the apparatus, while an assistant produced the sound, to observe at what distance I could distinctly hear it. The result of all my observations, as far as I could judge, was that the intensity of sound depends solely311 upon the density of the air in which it is made, and not at all upon any chemical principle in its constitution.

    “In inflammable air the sound of the bell was hardly to be distinguished from the same in a pretty good vacuum; and this air is ten times rarer than common air.

    “In fixed air the sound was much louder than in common air, so as to be heard about half as far again; and this air is in about the same proportion denser312 than common air.

    “In dephlogisticated air the sound was also sensibly louder than in common air, and, as I thought, rather more than in the proportion of its superior density; but of this I cannot pretend to be quite sure.

    213

    “In all these experiments the common standard was the sound of the same bell in the same receiver, every other circumstance also being the same; the air only being changed by removing the receiver from the transfer and blowing through it, etc.”

The sixth and last volume appeared in 1786 with a dedication to William Constable313, Esq., of Barton Constable.

In the preface Priestley is concerned to defend himself against the charge that he occupies himself too much with Theology to the detriment314 of Natural Philosophy. Theology, he pleads, is his original and proper province, and for which, therefore, he may be allowed to have a justifiable70 predilection315. But as with Metaphysics, so with Theology. Neither subject engrossed316 so much of his time as some persons imagined.

    “I am particularly complained of at present as having thrown away so much time on the composition of my History of the Corruptions317 of Christianity, and of the Opinions Concerning Christ. But I can assure them, and the nature of the thing, if they consider it, may satisfy them, that the time I must necessarily have bestowed318 upon the experiments, of which an account is contained in this single volume, is much more than I have given to the six, of which the above-mentioned works consist, and to all the controversial pieces that I have written in defence of the former of them. The labour and attention necessary to enable me to write single paragraphs in this work have been more than was requisite319 to compose whole sections or chapters of the former.... Besides, these different studies so relieve one another that I believe I do more in each of them, by applying to them alternately, than I should do if I gave my whole attention to one of them only.”

But Priestley’s main defence rests “on the superior dignity and importance of theological studies to any other whatever.” The whole preface must be read in the light of Priestley’s altered circumstances and of his 214 relations to the theological world, which, since his removal to Birmingham, had greatly increased in weight and importance. As already stated, he regarded himself as ordained320 to champion the cause of religion among the persons to whom his writings as a natural philosopher specially25 appealed. The author of the Institutes of Natural and Revealed Religion was the writer of the Letters to a Philosophical Unbeliever and, in an age of unbelief, the doughty321 antagonist322 of Gibbon. Otherwise the incongruous mixture of Theology and Natural Philosophy, of which the preface is made up, seems inexplicable323.

To the historian of chemistry the last volume of the series is hardly less interesting than any one of its predecessors, not so much as affording knowledge of new “airs” as by reason of Priestley’s relation to the waning324 doctrine of phlogiston, and on account of the part that his own work was playing, in spite of himself, in completing its overthrow. The volume indeed significantly opens with “Experiments relating to Phlogiston,” a reprint with notes of his paper in the 73rd volume of the Philosophical Transactions. Priestley truly says:—

    “There are few subjects, perhaps none, that have occasioned more perplexity to chemists than that of phlogiston, or, as it is sometimes called, the principle of inflammability. It was the great discovery of Stahl that this principle, whatever it be, is transferable from one substance to another, how different soever in their other properties, such as sulphur, wood, and all the metals, and therefore is the same thing in them all. But what has given an air of mystery to this subject has been that it was imagined that this principle, or substance, could not be exhibited except in combination with other substances, and could not be made to assume separately either a fluid or solid form. It was also asserted by some that phlogiston was 215 so far from adding to the weight of bodies that the addition of it made them really lighter than they were before; on which account they chose to call it the principle of levity325. This opinion had great patrons.

    “Of late it has been the opinion of many celebrated chemists, Mr Lavoisier among others, that the whole doctrine of phlogiston has been founded on mistake, and that in all cases in which it was thought that bodies parted with the principle of phlogiston, they in fact lost nothing, but on the contrary acquired something; and in most cases an addition of some kind of air; that a metal, for instance, was not a combination of two things, viz., an earth and phlogiston, but was probably a simple substance in its metallic state; and that the calx is produced not by the loss of phlogiston, or of anything else, but by the acquisition of air.”

He then goes on to say that the arguments in favour of this opinion, especially those which were drawn326 from the experiments of Lavoisier on mercury, were “so specious” that he owns he was much inclined to adopt it. But he was evidently loth to part company with a conception which had hitherto been the central idea of his chemical creed327, the very key-stone of the structure which he was pleased to regard as his philosophy. As an abstract conception, as the principle of levity, as something which was the negation328 of mass and which gravity repelled329, phlogiston was eminently unsatisfactory. But what if phlogiston were an entity330? A ponderable substance, no matter how light? In that case Stahl’s generalisation might still afford salvation331. “My friend, Mr Kirwan”—a clever, ingenious Irishman, with a nimble wit and a facile pen—supplied the hint—“Phlogiston was inflammable air”—and Priestley by a series of experiments, faultless as to execution but utterly fallacious as to interpretation332, persuades himself that Kirwan is right and that Mr Lavoisier’s opinion 216 and his “specious arguments” are therefore to be discountenanced. The paper, in certain respects, is one of the most noteworthy of Priestley’s productions. The experiments are original, ingenious and striking, but as an example of his inductive capacity, or as an indication of its author’s logical power, or of his ability to try judicially333 the very issue he has raised, it is significant only of the profound truth of his own words that

    “we may take a maxim so strongly for granted that the plainest evidence of sense will not entirely change, and often hardly modify, our persuasions; and the more ingenious a man is, the more effectually he is entangled in his errors, his ingenuity only helping him to deceive himself by evading the force of truth.”

The next paper in the volume, on “The Seeming Conversion of Water into Air,” is a record of experiments which cost Priestley much labour and the Lunar Society, for a time, much mystification. Priestley eventually detected the fallacy in the observation which originally induced him to believe that it was possible to transmute334 water into a permanently335 elastic fluid, but he got no further in his explanation than that air has a faculty336 of passing through the pores of an earthern vessel “by means of a power very different from that of pressure.”

This and the third paper in the series are classical, and this partly by reason of, and partly in spite of, their blunders, for they are the record of the work upon which James Watt largely based his conjectures concerning the real chemical nature of water, whereby his name has been associated with that of Cavendish and Lavoisier as the true discoverer of its composition. In the course of his inquiry Priestley studied the action of 217 steam upon red-hot iron by an arrangement generally similar to that employed by Lavoisier, but his explanation of the phenomena is essentially different from that of the French chemist, as may be seen from the following quotation:—

    “Since iron gains the same addition of weight by melting it in dephlogisticated air, and also by the addition of water when red-hot, and becomes, as I have already observed, in all respects the same substance, it is evident that this air or water, as existing in the iron, is the very same thing; and this can hardly be explained but upon the supposition that water consists of two kinds of air, viz., inflammable and dephlogisticated.”

This, however, is how Priestley actually does explain it:—

    “When iron is melted in dephlogisticated air we may suppose that, though part of its phlogiston escapes to enter into the composition of the small quantity of fixed air which is then procured, yet enough remains to form water with the addition of the dephlogisticated air which it has imbibed, so that this calx of iron consists of the intimate union of the pure earth of iron and of water; and therefore when the same calx, thus saturated337 with water, is exposed to heat in inflammable air, this air enters into it, destroys the attraction between the water and the earth, and revives the iron while the water is expelled in its proper form.

    “Consequently, in the process with steam, nothing is necessary to be supposed but the entrance of the water and the expulsion of the phlogiston belonging to the iron, no more phlogiston remaining in it than what the water brought along with it, and which is retained as a constituent part of the water or of the new compound.”

No more striking illustration of how a man’s ingenuity may help him to deceive himself could be given than is afforded by this passage. Priestley to the end of his days never got a just conception of the real chemical constitution of water.
218

The remaining papers call for little comment. In the course of some further inquiries Priestley discovered sulphuretted hydrogen, termed by him sulphurated inflammable air, and which he prepared by the action of oil of vitriol upon ferrous sulphide. This gas must of course have been frequently obtained or perceived by him, and possibly by others, as it is produced by a number of processes. Its characteristic smell was associated with sulphur: it was thought to be nothing but inflammable air modified or polluted by the accidental presence of sulphur. It cannot be held that Priestley drew the same sharp distinctions between the various kinds of inflammable air that we draw to-day. To us they are essentially different substances. Priestley, however, regarded them as in the main phlogiston combined or associated with other substances which affected the character of their flames or gave them different properties. In his opinion they were essentially the same. This fact serves to explain what is otherwise incomprehensible, and accounts for many of his mistakes.

The last paper in the volume, excluding the “Supplementary Observations,” has a special interest. It is entitled “Observations relating to Theory,” and is in fact Priestley’s Confession of Faith in the doctrine which enslaved and misled him throughout the whole of his scientific career. But he makes it so hesitatingly and with so many reservations that one wonders why he is constrained to make it at all. He appears to think, however, that it is expected of him.

    “It is always our endeavour, after making experiments, to generalise the conclusions we draw from them, and by this means to form a theory, or system of principles, to which all the facts may be reduced, and by means of which we may be able 219 to foretell338 the results of future experiments.... In my former publications I have frequently promised to give such a general theory of the experiments in which the different kinds of air are concerned, as the present state of our knowledge of them will enable me to do. But, like Simonides with respect to the question that was proposed to him concerning God, I have deferred339 it from time to time; and indeed I am more than ever disposed to defer340 it still longer, as I own that I am at present even less able to give such a theory as shall satisfy myself than I was some years ago; new difficulties having arisen, which unhinge former theories, and more experiments being necessary to establish new ones.

    “Fluctuating, however, as the present state of this branch of knowledge is, I do not think that I can, on this occasion, entirely decline giving some observations of a theoretical nature, and though I cannot pretend to perform the whole of my promise, I shall give a summary view of what appears to me to be the constituent parts of all the kinds of air with which we are acquainted, and a more particular account of the hypothesis concerning phlogiston, which is at present more an object of discussion than anything else of a theoretical nature.”

Priestley then passes in review all the “airs” of which the chemistry of his time had any knowledge, giving the elements or constituent principles of which he imagined them to be composed.

The only kind of air that he thinks to be properly elementary, and to consist of a simple substance, is dephlogisticated air, with possibly the addition of the principle of heat, which, as it is not probable that it adds to the weight of bodies, can hardly be called an element in their composition.

    “Dephlogisticated air appears to be one of the elements of water, of fixed air, of all the acids, and of many other substances which, till lately, have been thought to be simple. The air of the atmosphere, exclusive of a great variety of foreign impregnations, appears to consist of dephlogisticated and phlogisticated air.”

220

As regards phlogisticated air—the mephitic air of Rutherford, the azote of Lavoisier, the nitrogen of Chaptal—Priestley, reasoning from Cavendish’s work, concluded that it was probably not elementary, but “that it consists of nitrous acid and phlogiston; this acid having always been produced by decomposing341 it with ... dephlogisticated air.”

He is conscious, however, of the insufficiency of this hypothesis, and suggests

    “that the acid principle is supplied by the dephlogisticated air, while the nitrous air gives the base of the nitrous acid and phlogiston; and then this [phlogisticated] air may perhaps be considered as phlogiston combined not with all the necessary elements of nitrous acid, but only what may be called the base of it, viz., the dephlogisticated nitrous vapour, or something which when united to dephlogisticated air will constitute nitrous acid.”

“Fixed air (carbonic acid) seems to be a compound of phlogiston and dephlogisticated air.” In other words, carbonic acid and water have, according to Priestley, “the same elementary composition.” “It is something remarkable that two substances so different from each other as fixed air and water should be analysed into the same principles. But there is this difference between them, that water is the union not of pure phlogiston but of inflammable air and dephlogisticated air.”

Of the true nature of inflammable air, Priestley, as we have more than once had occasion to point out, had only the vaguest notions.

    “Inflammable air,” he says, “seems now to consist of water and inflammable air, which however seems extraordinary, as the two substances are hereby made to involve each other, one of the constituent parts of water being inflammable air, and one of the constituent parts of inflammable air being water; and therefore, if the experiments would favour it (but I do not see that they do so) it would be more natural to suppose that water, 221 like fixed air, consists of phlogiston and dephlogisticated air in some different mode of combination.”

That Priestley to the last imagined that the various kinds of inflammable air known to him were at bottom one and the same substance, modified or affected by other substances, accidental and unessential, might be proved by a number of passages. He says with respect to inflammable air generally:—

    “There is an astonishing variety in the different kinds of inflammable air, the cause of which is very imperfectly known. The lightest, and therefore, probably, the purest kind seems to consist of phlogiston and water only. But it is probable that oil, and that of different kinds, may be held in solution in several of them, and be the reason of their burning with a lambent flame, and also of their being so readily resolved into fixed air when they are decomposed with dephlogisticated air; though why this should be the case I cannot imagine.”

Nitrous air (nitric oxide) he conceives to be a combination of a dephlogisticated nitrous air and phlogiston, and that by adding to it dephlogisticated air and water it is converted into nitrous acid.

Dephlogisticated nitrous air (nitrous oxide) he conceives may, like dephlogisticated air, be an elementary substance and to be formed by depriving nitrous air of its phlogiston.

The various acid airs (e.g., marine acid air, vitriolic acid air, etc.) consist of the peculiar acids as vapours combined with phlogiston.

The Alkaline air (ammonia) he thought to consist of inflammable air and phlogisticated air (nitrogen),

    “or of something capable of being converted into phlogisticated air.... That water enters into the composition of alkaline air seems necessary to be admitted, because it is decomposed into inflammable air, which I cannot help thinking necessarily requires water. It seems, however, clearly to be inferred ... that there is no occasion to admit the alkaline principle into the 222 number of elements; the alkalinity, as I may say, some way or other, arising from phlogiston, or phlogisticated air, as acidity342 arises from dephlogisticated air.”

After these theoretical speculations, “in which,” he says, “I fear I have not communicated much light, though it is as much as I have been able to get,” Priestley proceeds to make some observations relating to phlogiston, “the existence of which is at present a great subject of discussion with philosophers; some maintaining that there is no such thing, and others holding the doctrine of Stahl on the subject.”

    “According to Stahl, phlogiston is a real substance, capable of being transferred from one body to another; its presence or absence making a remarkable difference in the properties of bodies, whether it add to their weight or not. Thus he concluded that oil of vitriol deprived of water, and united to phlogiston, becomes sulphur; and that the calces of metals, by the addition of the same substance, become metals.... What is now contended for is that in the oil of vitriol changing into sulphur something is lost and nothing gained, and also that a calx becomes a metal by the loss of air only. And did facts correspond to this theory it would certainly be preferable to that of Stahl, as being more simple; there being one principle less to take into our account in explaining the changes of bodies. But I do not know of any case in which phlogiston has been supposed to enter into a body, but there is room to suppose that something does enter into it....

    “What has been insisted upon, as most favourable to the exclusion343 of phlogiston, is the revival344 of mercury without the addition of any other substance from the precipitate per se. In this case it is evident that mere heat ... is sufficient to revive the metal. And as what is expelled from this calx is the purest dephlogisticated air, it has been said that mercury is changed into this calx by imbibing pure air, and therefore becomes a metal again, merely in consequence of parting with that air.”

The dexterous345 Mr Kirwan, not long before he himself embraced the French doctrine, furnished Priestley with 223 an argument which satisfied him that this cardinal fact can be accounted for without excluding phlogiston. “Since therefore the supposition is exceedingly convenient, if not absolutely necessary, to the explanation of many other facts in chemistry, it is at least advisable not to abandon it.”

    “That calces do not become metals merely by parting with the air they contain, is evident from my experiments on heating them in contact with inflammable air, in which the inflammable air, or some necessary part of it, is undoubtedly absorbed; and though a little moisture be deposited in the process, it may well be supposed to be that which in conjunction with phlogiston constituted the inflammable air. And what can the other principle that is absorbed by the calx be but the same thing which, when united to water, is recovered again from the metal and found to be inflammable air having all the same properties with that which was employed in the revival of it. Metals therefore are not simple substances, but consist of their calces, and something else which they take from inflammable air. And as the same may also be taken from any combustible346 substance, it corresponds exactly to Stahl’s phlogiston, and therefore the doctrine of it is confirmed by these experiments; that is, we must still say that in all combustible substances there is a principle capable of being transferred to other substances, which when united to the calces of metals makes them to be metals, and which, united to oil of vitriol (deprived of its water) makes it to be sulphur.”

Thus was the ingenious man effectually entangled in his errors, his ingenuity helping him to deceive himself by evading the force of truth. To err46 is human. If Priestley saw through a glass darkly, and but dimly discerned the truth, he at least strove, so far as in him lay, to reach the light. Posterity forgives, and may well forget, his errors in grateful recognition of the many noble services he rendered to our common humanity, and in humbling347 recollection of the suffering and sacrifice with which those services were requited348.

The End

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1 atmospheric 6eayR     
adj.大气的,空气的;大气层的;大气所引起的
参考例句:
  • Sea surface temperatures and atmospheric circulation are strongly coupled.海洋表面温度与大气环流是密切相关的。
  • Clouds return radiant energy to the surface primarily via the atmospheric window.云主要通过大气窗区向地表辐射能量。
2 oxide K4dz8     
n.氧化物
参考例句:
  • Oxide is usually seen in our daily life.在我们的日常生活中氧化物很常见。
  • How can you get rid of this oxide coating?你们该怎样除去这些氧化皮?
3 par OK0xR     
n.标准,票面价值,平均数量;adj.票面的,平常的,标准的
参考例句:
  • Sales of nylon have been below par in recent years.近年来尼龙织品的销售额一直不及以往。
  • I don't think his ability is on a par with yours.我认为他的能力不能与你的能力相媲美。
4 silicon dykwJ     
n.硅(旧名矽)
参考例句:
  • This company pioneered the use of silicon chip.这家公司开创了使用硅片的方法。
  • A chip is a piece of silicon about the size of a postage stamp.芯片就是一枚邮票大小的硅片。
5 diffusion dl4zm     
n.流布;普及;散漫
参考例句:
  • The invention of printing helped the diffusion of learning.印刷术的发明有助于知识的传播。
  • The effect of the diffusion capacitance can be troublesome.扩散电容会引起麻烦。
6 respiration us7yt     
n.呼吸作用;一次呼吸;植物光合作用
参考例句:
  • They tried artificial respiration but it was of no avail.他们试做人工呼吸,可是无效。
  • They made frequent checks on his respiration,pulse and blood.他们经常检查他的呼吸、脉搏和血液。
7 conversion UZPyI     
n.转化,转换,转变
参考例句:
  • He underwent quite a conversion.他彻底变了。
  • Waste conversion is a part of the production process.废物处理是生产过程的一个组成部分。
8 watt Lggwo     
n.瓦,瓦特
参考例句:
  • The invention of the engine is creditable to Watt.发动机的发明归功于瓦特。
  • The unit of power is watt.功率的单位是瓦特。
9 confession 8Ygye     
n.自白,供认,承认
参考例句:
  • Her confession was simply tantamount to a casual explanation.她的自白简直等于一篇即席说明。
  • The police used torture to extort a confession from him.警察对他用刑逼供。
10 inquiry nbgzF     
n.打听,询问,调查,查问
参考例句:
  • Many parents have been pressing for an inquiry into the problem.许多家长迫切要求调查这个问题。
  • The field of inquiry has narrowed down to five persons.调查的范围已经缩小到只剩5个人了。
11 conspicuous spszE     
adj.明眼的,惹人注目的;炫耀的,摆阔气的
参考例句:
  • It is conspicuous that smoking is harmful to health.很明显,抽烟对健康有害。
  • Its colouring makes it highly conspicuous.它的色彩使它非常惹人注目。
12 essentially nntxw     
adv.本质上,实质上,基本上
参考例句:
  • Really great men are essentially modest.真正的伟人大都很谦虚。
  • She is an essentially selfish person.她本质上是个自私自利的人。
13 mere rC1xE     
adj.纯粹的;仅仅,只不过
参考例句:
  • That is a mere repetition of what you said before.那不过是重复了你以前讲的话。
  • It's a mere waste of time waiting any longer.再等下去纯粹是浪费时间。
14 modifications aab0760046b3cea52940f1668245e65d     
n.缓和( modification的名词复数 );限制;更改;改变
参考例句:
  • The engine was pulled apart for modifications and then reassembled. 发动机被拆开改型,然后再组装起来。 来自《简明英汉词典》
  • The original plan had undergone fairly extensive modifications. 原计划已经作了相当大的修改。 来自《简明英汉词典》
15 modification tEZxm     
n.修改,改进,缓和,减轻
参考例句:
  • The law,in its present form,is unjust;it needs modification.现行的法律是不公正的,它需要修改。
  • The design requires considerable modification.这个设计需要作大的修改。
16 affected TzUzg0     
adj.不自然的,假装的
参考例句:
  • She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
  • His manners are affected.他的态度不自然。
17 doctrine Pkszt     
n.教义;主义;学说
参考例句:
  • He was impelled to proclaim his doctrine.他不得不宣扬他的教义。
  • The council met to consider changes to doctrine.宗教议会开会考虑更改教义。
18 overthrow PKDxo     
v.推翻,打倒,颠覆;n.推翻,瓦解,颠覆
参考例句:
  • After the overthrow of the government,the country was in chaos.政府被推翻后,这个国家处于混乱中。
  • The overthrow of his plans left him much discouraged.他的计划的失败使得他很气馁。
19 philosophical rN5xh     
adj.哲学家的,哲学上的,达观的
参考例句:
  • The teacher couldn't answer the philosophical problem.老师不能解答这个哲学问题。
  • She is very philosophical about her bad luck.她对自己的不幸看得很开。
20 speculative uvjwd     
adj.思索性的,暝想性的,推理的
参考例句:
  • Much of our information is speculative.我们的许多信息是带推测性的。
  • The report is highly speculative and should be ignored.那个报道推测的成分很大,不应理会。
21 eminently c442c1e3a4b0ad4160feece6feb0aabf     
adv.突出地;显著地;不寻常地
参考例句:
  • She seems eminently suitable for the job. 她看来非常适合这个工作。
  • It was an eminently respectable boarding school. 这是所非常好的寄宿学校。 来自《简明英汉词典》
22 eminent dpRxn     
adj.显赫的,杰出的,有名的,优良的
参考例句:
  • We are expecting the arrival of an eminent scientist.我们正期待一位著名科学家的来访。
  • He is an eminent citizen of China.他是一个杰出的中国公民。
23 disparaged ff1788e428b44c5ea75417fb2d561704     
v.轻视( disparage的过去式和过去分词 );贬低;批评;非难
参考例句:
  • French-Canadian fur trappers and Sioux disparaged such country as "bad lands. " 法语的加拿大毛皮捕兽器和苏人的贬低国家作为“坏土地”。 来自互联网
  • She disparaged her student's efforts. 她轻视她的学生做出的努力。 来自互联网
24 disparage nldzJ     
v.贬抑,轻蔑
参考例句:
  • Your behaviour will disparage the whole family.你的行为将使全家丢脸。
  • Never disparage yourself or minimize your strength or power.不要贬低你自己或降低你的力量或能力。
25 specially Hviwq     
adv.特定地;特殊地;明确地
参考例句:
  • They are specially packaged so that they stack easily.它们经过特别包装以便于堆放。
  • The machine was designed specially for demolishing old buildings.这种机器是专为拆毁旧楼房而设计的。
26 uproot 3jCwL     
v.连根拔起,拔除;根除,灭绝;赶出家园,被迫移开
参考例句:
  • The family decided to uproot themselves and emigrate to Australia.他们全家决定离开故土,移居澳大利亚。
  • The trunk of an elephant is powerful enough to uproot trees.大象的长鼻强壮得足以将树木连根拔起。
27 immediate aapxh     
adj.立即的;直接的,最接近的;紧靠的
参考例句:
  • His immediate neighbours felt it their duty to call.他的近邻认为他们有责任去拜访。
  • We declared ourselves for the immediate convocation of the meeting.我们主张立即召开这个会议。
28 predecessors b59b392832b9ce6825062c39c88d5147     
n.前任( predecessor的名词复数 );前辈;(被取代的)原有事物;前身
参考例句:
  • The new government set about dismantling their predecessors' legislation. 新政府正着手废除其前任所制定的法律。 来自《简明英汉词典》
  • Will new plan be any more acceptable than its predecessors? 新计划比原先的计划更能令人满意吗? 来自《简明英汉词典》
29 phenomena 8N9xp     
n.现象
参考例句:
  • Ade couldn't relate the phenomena with any theory he knew.艾德无法用他所知道的任何理论来解释这种现象。
  • The object of these experiments was to find the connection,if any,between the two phenomena.这些实验的目的就是探索这两种现象之间的联系,如果存在着任何联系的话。
30 industrious a7Axr     
adj.勤劳的,刻苦的,奋发的
参考例句:
  • If the tiller is industrious,the farmland is productive.人勤地不懒。
  • She was an industrious and willing worker.她是个勤劳肯干的员工。
31 truthful OmpwN     
adj.真实的,说实话的,诚实的
参考例句:
  • You can count on him for a truthful report of the accident.你放心,他会对事故作出如实的报告的。
  • I don't think you are being entirely truthful.我认为你并没全讲真话。
32 bias 0QByQ     
n.偏见,偏心,偏袒;vt.使有偏见
参考例句:
  • They are accusing the teacher of political bias in his marking.他们在指控那名教师打分数有政治偏见。
  • He had a bias toward the plan.他对这项计划有偏见。
33 impartial eykyR     
adj.(in,to)公正的,无偏见的
参考例句:
  • He gave an impartial view of the state of affairs in Ireland.他对爱尔兰的事态发表了公正的看法。
  • Careers officers offer impartial advice to all pupils.就业指导员向所有学生提供公正无私的建议。
34 entirely entirely     
ad.全部地,完整地;完全地,彻底地
参考例句:
  • The fire was entirely caused by their neglect of duty. 那场火灾完全是由于他们失职而引起的。
  • His life was entirely given up to the educational work. 他的一生统统献给了教育工作。
35 divination LPJzf     
n.占卜,预测
参考例句:
  • Divination is made up of a little error and superstition,plus a lot of fraud.占卜是由一些谬误和迷信构成,再加上大量的欺骗。
  • Katherine McCormack goes beyond horoscopes and provides a quick guide to other forms of divination.凯瑟琳·麦考马克超越了占星并给其它形式的预言提供了快速的指导。
36 insistent s6ZxC     
adj.迫切的,坚持的
参考例句:
  • There was an insistent knock on my door.我听到一阵急促的敲门声。
  • He is most insistent on this point.他在这点上很坚持。
37 irony P4WyZ     
n.反语,冷嘲;具有讽刺意味的事,嘲弄
参考例句:
  • She said to him with slight irony.她略带嘲讽地对他说。
  • In her voice we could sense a certain tinge of irony.从她的声音里我们可以感到某种讥讽的意味。
38 perpetuate Q3Cz2     
v.使永存,使永记不忘
参考例句:
  • This monument was built to perpetuate the memory of the national hero.这个纪念碑建造的意义在于纪念民族英雄永垂不朽。
  • We must perpetuate the system.我们必须将此制度永久保持。
39 esteem imhyZ     
n.尊敬,尊重;vt.尊重,敬重;把…看作
参考例句:
  • I did not esteem him to be worthy of trust.我认为他不值得信赖。
  • The veteran worker ranks high in public love and esteem.那位老工人深受大伙的爱戴。
40 zeal mMqzR     
n.热心,热情,热忱
参考例句:
  • Revolutionary zeal caught them up,and they joined the army.革命热情激励他们,于是他们从军了。
  • They worked with great zeal to finish the project.他们热情高涨地工作,以期完成这个项目。
41 thereby Sokwv     
adv.因此,从而
参考例句:
  • I have never been to that city,,ereby I don't know much about it.我从未去过那座城市,因此对它不怎么熟悉。
  • He became a British citizen,thereby gaining the right to vote.他成了英国公民,因而得到了投票权。
42 posterity D1Lzn     
n.后裔,子孙,后代
参考例句:
  • Few of his works will go down to posterity.他的作品没有几件会流传到后世。
  • The names of those who died are recorded for posterity on a tablet at the back of the church.死者姓名都刻在教堂后面的一块石匾上以便后人铭记。
43 appreciation Pv9zs     
n.评价;欣赏;感谢;领会,理解;价格上涨
参考例句:
  • I would like to express my appreciation and thanks to you all.我想对你们所有人表达我的感激和谢意。
  • I'll be sending them a donation in appreciation of their help.我将送给他们一笔捐款以感谢他们的帮助。
44 ascertain WNVyN     
vt.发现,确定,查明,弄清
参考例句:
  • It's difficult to ascertain the coal deposits.煤储量很难探明。
  • We must ascertain the responsibility in light of different situtations.我们必须根据不同情况判定责任。
45 ascertained e6de5c3a87917771a9555db9cf4de019     
v.弄清,确定,查明( ascertain的过去式和过去分词 )
参考例句:
  • The previously unidentified objects have now been definitely ascertained as being satellites. 原来所说的不明飞行物现在已证实是卫星。 来自《简明英汉词典》
  • I ascertained that she was dead. 我断定她已经死了。 来自《简明英汉词典》
46 err 2izzk     
vi.犯错误,出差错
参考例句:
  • He did not err by a hair's breadth in his calculation.他的计算结果一丝不差。
  • The arrows err not from their aim.箭无虚发。
47 undoubtedly Mfjz6l     
adv.确实地,无疑地
参考例句:
  • It is undoubtedly she who has said that.这话明明是她说的。
  • He is undoubtedly the pride of China.毫无疑问他是中国的骄傲。
48 surmise jHiz8     
v./n.猜想,推测
参考例句:
  • It turned out that my surmise was correct.结果表明我的推测没有错。
  • I surmise that he will take the job.我推测他会接受这份工作。
49 verge gUtzQ     
n.边,边缘;v.接近,濒临
参考例句:
  • The country's economy is on the verge of collapse.国家的经济已到了崩溃的边缘。
  • She was on the verge of bursting into tears.她快要哭出来了。
50 cardinal Xcgy5     
n.(天主教的)红衣主教;adj.首要的,基本的
参考例句:
  • This is a matter of cardinal significance.这是非常重要的事。
  • The Cardinal coloured with vexation. 红衣主教感到恼火,脸涨得通红。
51 eluded 8afea5b7a29fab905a2d34ae6f94a05f     
v.(尤指机敏地)避开( elude的过去式和过去分词 );逃避;躲避;使达不到
参考例句:
  • The sly fox nimbly eluded the dogs. 那只狡猾的狐狸灵活地躲避开那群狗。 来自《现代汉英综合大词典》
  • The criminal eluded the police. 那个罪犯甩掉了警察的追捕。 来自《现代英汉综合大词典》
52 chagrin 1cyyX     
n.懊恼;气愤;委屈
参考例句:
  • His increasingly visible chagrin sets up a vicious circle.他的明显的不满引起了一种恶性循环。
  • Much to his chagrin,he did not win the race.使他大为懊恼的是他赛跑没获胜。
53 underlying 5fyz8c     
adj.在下面的,含蓄的,潜在的
参考例句:
  • The underlying theme of the novel is very serious.小说隐含的主题是十分严肃的。
  • This word has its underlying meaning.这个单词有它潜在的含义。
54 density rOdzZ     
n.密集,密度,浓度
参考例句:
  • The population density of that country is 685 per square mile.那个国家的人口密度为每平方英里685人。
  • The region has a very high population density.该地区的人口密度很高。
55 perfectly 8Mzxb     
adv.完美地,无可非议地,彻底地
参考例句:
  • The witnesses were each perfectly certain of what they said.证人们个个对自己所说的话十分肯定。
  • Everything that we're doing is all perfectly above board.我们做的每件事情都是光明正大的。
56 noted 5n4zXc     
adj.著名的,知名的
参考例句:
  • The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
  • Jim is noted for arriving late for work.吉姆上班迟到出了名。
57 glimmer 5gTxU     
v.发出闪烁的微光;n.微光,微弱的闪光
参考例句:
  • I looked at her and felt a glimmer of hope.我注视她,感到了一线希望。
  • A glimmer of amusement showed in her eyes.她的眼中露出一丝笑意。
58 refreshing HkozPQ     
adj.使精神振作的,使人清爽的,使人喜欢的
参考例句:
  • I find it'so refreshing to work with young people in this department.我发现和这一部门的青年一起工作令人精神振奋。
  • The water was cold and wonderfully refreshing.水很涼,特别解乏提神。
59 prolixity 00e3e4d84878a083a88c7fbddd42835c     
n.冗长,罗嗦
参考例句:
  • As we know prolixity is a big shortcoming to write articles. 众所周知,罗嗦是写文章的大忌。 来自辞典例句
  • Otherwise,it will probably make misunderstanding,and make the version prolixity. 否则,就可能造成理解错误,或使译文冗长罗嗦。 来自互联网
60 prolix z0fzz     
adj.罗嗦的;冗长的
参考例句:
  • Too much speaking makes it a little prolix.说那么多,有些罗嗦了。
  • Her style is tediously prolix.她的文章冗长而乏味。
61 transparent Smhwx     
adj.明显的,无疑的;透明的
参考例句:
  • The water is so transparent that we can see the fishes swimming.水清澈透明,可以看到鱼儿游来游去。
  • The window glass is transparent.窗玻璃是透明的。
62 dedications dc6a42911d354327bba879801a5173db     
奉献( dedication的名词复数 ); 献身精神; 教堂的)献堂礼; (书等作品上的)题词
参考例句:
63 dedication pxMx9     
n.奉献,献身,致力,题献,献辞
参考例句:
  • We admire her courage,compassion and dedication.我们钦佩她的勇气、爱心和奉献精神。
  • Her dedication to her work was admirable.她对工作的奉献精神可钦可佩。
64 peculiar cinyo     
adj.古怪的,异常的;特殊的,特有的
参考例句:
  • He walks in a peculiar fashion.他走路的样子很奇特。
  • He looked at me with a very peculiar expression.他用一种很奇怪的表情看着我。
65 ingenuous mbNz0     
adj.纯朴的,单纯的;天真的;坦率的
参考例句:
  • Only the most ingenuous person would believe such a weak excuse!只有最天真的人才会相信这么一个站不住脚的借口!
  • With ingenuous sincerity,he captivated his audience.他以自己的率真迷住了观众。
66 precludes a6099ad5ef93a1df2eb33804a8db6373     
v.阻止( preclude的第三人称单数 );排除;妨碍;使…行不通
参考例句:
  • Lack of time precludes any further discussion. 由于时间不足,不可能进行深入的讨论。
  • The surface reactivity of many nonblack fillers generally precludes strong bonding with this type of matrix. 许多非碳黑填料的表面反应性一般阻碍与该种基质形成牢固的粘结。 来自辞典例句
67 elucidate GjSzd     
v.阐明,说明
参考例句:
  • The note help to elucidate the most difficult parts of the text.这些注释有助于弄清文中最难懂的部分。
  • This guide will elucidate these differences and how to exploit them.这篇指导将会阐述这些不同点以及如何正确利用它们。
68 decided lvqzZd     
adj.决定了的,坚决的;明显的,明确的
参考例句:
  • This gave them a decided advantage over their opponents.这使他们比对手具有明显的优势。
  • There is a decided difference between British and Chinese way of greeting.英国人和中国人打招呼的方式有很明显的区别。
69 approbation INMyt     
n.称赞;认可
参考例句:
  • He tasted the wine of audience approbation.他尝到了像酒般令人陶醉的听众赞许滋味。
  • The result has not met universal approbation.该结果尚未获得普遍认同。
70 justifiable a3ExP     
adj.有理由的,无可非议的
参考例句:
  • What he has done is hardly justifiable.他的所作所为说不过去。
  • Justifiable defense is the act being exempted from crimes.正当防卫不属于犯罪行为。
71 prodigious C1ZzO     
adj.惊人的,奇妙的;异常的;巨大的;庞大的
参考例句:
  • This business generates cash in prodigious amounts.这种业务收益丰厚。
  • He impressed all who met him with his prodigious memory.他惊人的记忆力让所有见过他的人都印象深刻。
72 judgment e3xxC     
n.审判;判断力,识别力,看法,意见
参考例句:
  • The chairman flatters himself on his judgment of people.主席自认为他审视人比别人高明。
  • He's a man of excellent judgment.他眼力过人。
73 penetration 1M8xw     
n.穿透,穿人,渗透
参考例句:
  • He is a man of penetration.他是一个富有洞察力的人。
  • Our aim is to achieve greater market penetration.我们的目标是进一步打入市场。
74 ingratitude O4TyG     
n.忘恩负义
参考例句:
  • Tim's parents were rather hurt by his ingratitude.蒂姆的父母对他的忘恩负义很痛心。
  • His friends were shocked by his ingratitude to his parents.他对父母不孝,令他的朋友们大为吃惊。
75 gratitude p6wyS     
adj.感激,感谢
参考例句:
  • I have expressed the depth of my gratitude to him.我向他表示了深切的谢意。
  • She could not help her tears of gratitude rolling down her face.她感激的泪珠禁不住沿着面颊流了下来。
76 simplicity Vryyv     
n.简单,简易;朴素;直率,单纯
参考例句:
  • She dressed with elegant simplicity.她穿着朴素高雅。
  • The beauty of this plan is its simplicity.简明扼要是这个计划的一大特点。
77 inquiries 86a54c7f2b27c02acf9fcb16a31c4b57     
n.调查( inquiry的名词复数 );疑问;探究;打听
参考例句:
  • He was released on bail pending further inquiries. 他获得保释,等候进一步调查。
  • I have failed to reach them by postal inquiries. 我未能通过邮政查询与他们取得联系。 来自《现代汉英综合大词典》
78 pretensions 9f7f7ffa120fac56a99a9be28790514a     
自称( pretension的名词复数 ); 自命不凡; 要求; 权力
参考例句:
  • The play mocks the pretensions of the new middle class. 这出戏讽刺了新中产阶级的装模作样。
  • The city has unrealistic pretensions to world-class status. 这个城市不切实际地标榜自己为国际都市。
79 distress 3llzX     
n.苦恼,痛苦,不舒适;不幸;vt.使悲痛
参考例句:
  • Nothing could alleviate his distress.什么都不能减轻他的痛苦。
  • Please don't distress yourself.请你不要忧愁了。
80 lesser UpxzJL     
adj.次要的,较小的;adv.较小地,较少地
参考例句:
  • Kept some of the lesser players out.不让那些次要的球员参加联赛。
  • She has also been affected,but to a lesser degree.她也受到波及,但程度较轻。
81 rectify 8AezO     
v.订正,矫正,改正
参考例句:
  • The matter will rectify itself in a few days.那件事过几天就会变好。
  • You can rectify this fault if you insert a slash.插人一条斜线便可以纠正此错误。
82 envious n8SyX     
adj.嫉妒的,羡慕的
参考例句:
  • I don't think I'm envious of your success.我想我并不嫉妒你的成功。
  • She is envious of Jane's good looks and covetous of her car.她既忌妒简的美貌又垂涎她的汽车。
83 malignant Z89zY     
adj.恶性的,致命的;恶意的,恶毒的
参考例句:
  • Alexander got a malignant slander.亚历山大受到恶意的诽谤。
  • He started to his feet with a malignant glance at Winston.他爬了起来,不高兴地看了温斯顿一眼。
84 worthy vftwB     
adj.(of)值得的,配得上的;有价值的
参考例句:
  • I did not esteem him to be worthy of trust.我认为他不值得信赖。
  • There occurred nothing that was worthy to be mentioned.没有值得一提的事发生。
85 mortified 0270b705ee76206d7730e7559f53ea31     
v.使受辱( mortify的过去式和过去分词 );伤害(人的感情);克制;抑制(肉体、情感等)
参考例句:
  • She was mortified to realize he had heard every word she said. 她意识到自己的每句话都被他听到了,直羞得无地自容。
  • The knowledge of future evils mortified the present felicities. 对未来苦难的了解压抑了目前的喜悦。 来自《简明英汉词典》
86 maxim G2KyJ     
n.格言,箴言
参考例句:
  • Please lay the maxim to your heart.请把此格言记在心里。
  • "Waste not,want not" is her favourite maxim.“不浪费则不匮乏”是她喜爱的格言。
87 narrative CFmxS     
n.叙述,故事;adj.叙事的,故事体的
参考例句:
  • He was a writer of great narrative power.他是一位颇有记述能力的作家。
  • Neither author was very strong on narrative.两个作者都不是很善于讲故事。
88 concisely Jvwzw5     
adv.简明地
参考例句:
  • These equations are written more concisely as a single columnmatrix equation. 这些方程以单列矩阵方程表示会更简单。 来自辞典例句
  • The fiber morphology can be concisely summarized. 可以对棉纤维的形态结构进行扼要地归纳。 来自辞典例句
89 swelling OUzzd     
n.肿胀
参考例句:
  • Use ice to reduce the swelling. 用冰敷消肿。
  • There is a marked swelling of the lymph nodes. 淋巴结处有明显的肿块。
90 pompous 416zv     
adj.傲慢的,自大的;夸大的;豪华的
参考例句:
  • He was somewhat pompous and had a high opinion of his own capabilities.他有点自大,自视甚高。
  • He is a good man underneath his pompous appearance. 他的外表虽傲慢,其实是个好人。
91 receding c22972dfbef8589fece6affb72f431d1     
v.逐渐远离( recede的现在分词 );向后倾斜;自原处后退或避开别人的注视;尤指问题
参考例句:
  • Desperately he struck out after the receding lights of the yacht. 游艇的灯光渐去渐远,他拼命划水追赶。 来自辞典例句
  • Sounds produced by vehicles receding from us seem lower-pitched than usual. 渐渐远离我们的运载工具发出的声似乎比平常的音调低。 来自辞典例句
92 abounded 40814edef832fbadb4cebe4735649eb5     
v.大量存在,充满,富于( abound的过去式和过去分词 )
参考例句:
  • Get-rich-quick schemes abounded, and many people lost their savings. “生财之道”遍地皆是,然而许多人一生积攒下来的钱转眼之间付之东流。 来自英汉非文学 - 政府文件
  • Shoppers thronged the sidewalks. Olivedrab and navy-blue uniforms abounded. 人行道上逛商店的人摩肩接踵,身着草绿色和海军蓝军装的军人比比皆是。 来自辞典例句
93 extirpating f0c51c6a65e56da16f46a1738f641978     
v.消灭,灭绝( extirpate的现在分词 );根除
参考例句:
94 undue Vf8z6V     
adj.过分的;不适当的;未到期的
参考例句:
  • Don't treat the matter with undue haste.不要过急地处理此事。
  • It would be wise not to give undue importance to his criticisms.最好不要过分看重他的批评。
95 usurped ebf643e98bddc8010c4af826bcc038d3     
篡夺,霸占( usurp的过去式和过去分词 ); 盗用; 篡夺,篡权
参考例句:
  • That magazine usurped copyrighted material. 那杂志盗用了版权为他人所有的素材。
  • The expression'social engineering'has been usurped by the Utopianist without a shadow of light. “社会工程”这个词已被乌托邦主义者毫无理由地盗用了。
96 hierarchy 7d7xN     
n.等级制度;统治集团,领导层
参考例句:
  • There is a rigid hierarchy of power in that country.那个国家有一套严密的权力等级制度。
  • She's high up in the management hierarchy.她在管理阶层中地位很高。
97 lasting IpCz02     
adj.永久的,永恒的;vbl.持续,维持
参考例句:
  • The lasting war debased the value of the dollar.持久的战争使美元贬值。
  • We hope for a lasting settlement of all these troubles.我们希望这些纠纷能获得永久的解决。
98 benefactor ZQEy0     
n. 恩人,行善的人,捐助人
参考例句:
  • The chieftain of that country is disguised as a benefactor this time. 那个国家的首领这一次伪装出一副施恩者的姿态。
  • The first thing I did, was to recompense my original benefactor, my good old captain. 我所做的第一件事, 就是报答我那最初的恩人, 那位好心的老船长。
99 trifling SJwzX     
adj.微不足道的;没什么价值的
参考例句:
  • They quarreled over a trifling matter.他们为这种微不足道的事情争吵。
  • So far Europe has no doubt, gained a real conveniency,though surely a very trifling one.直到现在为止,欧洲无疑地已经获得了实在的便利,不过那确是一种微不足道的便利。
100 retirement TWoxH     
n.退休,退职
参考例句:
  • She wanted to enjoy her retirement without being beset by financial worries.她想享受退休生活而不必为金钱担忧。
  • I have to put everything away for my retirement.我必须把一切都积蓄起来以便退休后用。
101 perused 21fd1593b2d74a23f25b2a6c4dbd49b5     
v.读(某篇文字)( peruse的过去式和过去分词 );(尤指)细阅;审阅;匆匆读或心不在焉地浏览(某篇文字)
参考例句:
  • I remained under the wall and perused Miss Cathy's affectionate composition. 我就留在墙跟底下阅读凯蒂小姐的爱情作品。 来自辞典例句
  • Have you perused this article? 你细读了这篇文章了吗? 来自互联网
102 elastic Tjbzq     
n.橡皮圈,松紧带;adj.有弹性的;灵活的
参考例句:
  • Rubber is an elastic material.橡胶是一种弹性材料。
  • These regulations are elastic.这些规定是有弹性的。
103 elasticity 8jlzp     
n.弹性,伸缩力
参考例句:
  • The skin eventually loses its elasticity.皮肤最终会失去弹性。
  • Every sort of spring has a definite elasticity.每一种弹簧都有一定的弹性。
104 remarkable 8Vbx6     
adj.显著的,异常的,非凡的,值得注意的
参考例句:
  • She has made remarkable headway in her writing skills.她在写作技巧方面有了长足进步。
  • These cars are remarkable for the quietness of their engines.这些汽车因发动机没有噪音而不同凡响。
105 lighter 5pPzPR     
n.打火机,点火器;驳船;v.用驳船运送;light的比较级
参考例句:
  • The portrait was touched up so as to make it lighter.这张画经过润色,色调明朗了一些。
  • The lighter works off the car battery.引燃器利用汽车蓄电池打火。
106 gunpowder oerxm     
n.火药
参考例句:
  • Gunpowder was introduced into Europe during the first half of the 14th century.在14世纪上半叶,火药传入欧洲。
  • This statement has a strong smell of gunpowder.这是一篇充满火药味的声明。
107 caverns bb7d69794ba96943881f7baad3003450     
大山洞,大洞穴( cavern的名词复数 )
参考例句:
  • Within were dark caverns; what was inside them, no one could see. 里面是一个黑洞,这里面有什么东西,谁也望不见。 来自汉英文学 - 家(1-26) - 家(1-26)
  • UNDERGROUND Under water grottos, caverns Filled with apes That eat figs. 在水帘洞里,挤满了猿争吃无花果。
108 cane RsNzT     
n.手杖,细长的茎,藤条;v.以杖击,以藤编制的
参考例句:
  • This sugar cane is quite a sweet and juicy.这甘蔗既甜又多汁。
  • English schoolmasters used to cane the boys as a punishment.英国小学老师过去常用教鞭打男学生作为惩罚。
109 fermenting fdd52e85d75b46898edb910a097ddbf6     
v.(使)发酵( ferment的现在分词 );(使)激动;骚动;骚扰
参考例句:
  • The fermenting wine has bubbled up and over the top. 发酵的葡萄酒已经冒泡,溢了出来。 来自辞典例句
  • It must be processed through methods like boiling, grinding or fermenting. 它必须通过煮沸、研磨、或者发酵等方法加工。 来自互联网
110 fixed JsKzzj     
adj.固定的,不变的,准备好的;(计算机)固定的
参考例句:
  • Have you two fixed on a date for the wedding yet?你们俩选定婚期了吗?
  • Once the aim is fixed,we should not change it arbitrarily.目标一旦确定,我们就不应该随意改变。
111 esteemed ftyzcF     
adj.受人尊敬的v.尊敬( esteem的过去式和过去分词 );敬重;认为;以为
参考例句:
  • The art of conversation is highly esteemed in France. 在法国十分尊重谈话技巧。 来自《简明英汉词典》
  • He esteemed that he understood what I had said. 他认为已经听懂我说的意思了。 来自《简明英汉词典》
112 standing 2hCzgo     
n.持续,地位;adj.永久的,不动的,直立的,不流动的
参考例句:
  • After the earthquake only a few houses were left standing.地震过后只有几幢房屋还立着。
  • They're standing out against any change in the law.他们坚决反对对法律做任何修改。
113 apparatus ivTzx     
n.装置,器械;器具,设备
参考例句:
  • The school's audio apparatus includes films and records.学校的视听设备包括放映机和录音机。
  • They had a very refined apparatus.他们有一套非常精良的设备。
114 ingenuity 77TxM     
n.别出心裁;善于发明创造
参考例句:
  • The boy showed ingenuity in making toys.那个小男孩做玩具很有创造力。
  • I admire your ingenuity and perseverance.我钦佩你的别出心裁和毅力。
115 fully Gfuzd     
adv.完全地,全部地,彻底地;充分地
参考例句:
  • The doctor asked me to breathe in,then to breathe out fully.医生让我先吸气,然后全部呼出。
  • They soon became fully integrated into the local community.他们很快就完全融入了当地人的圈子。
116 gaseous Hlvy2     
adj.气体的,气态的
参考例句:
  • Air whether in the gaseous or liquid state is a fluid.空气,无论是气态的或是液态的,都是一种流体。
  • Freon exists both in liquid and gaseous states.氟利昂有液态和气态两种形态。
117 dealing NvjzWP     
n.经商方法,待人态度
参考例句:
  • This store has an excellent reputation for fair dealing.该商店因买卖公道而享有极高的声誉。
  • His fair dealing earned our confidence.他的诚实的行为获得我们的信任。
118 Vogue 6hMwC     
n.时髦,时尚;adj.流行的
参考例句:
  • Flowery carpets became the vogue.花卉地毯变成了时髦货。
  • Short hair came back into vogue about ten years ago.大约十年前短发又开始流行起来了。
119 sufficiently 0htzMB     
adv.足够地,充分地
参考例句:
  • It turned out he had not insured the house sufficiently.原来他没有给房屋投足保险。
  • The new policy was sufficiently elastic to accommodate both views.新政策充分灵活地适用两种观点。
120 strictly GtNwe     
adv.严厉地,严格地;严密地
参考例句:
  • His doctor is dieting him strictly.他的医生严格规定他的饮食。
  • The guests were seated strictly in order of precedence.客人严格按照地位高低就座。
121 applied Tz2zXA     
adj.应用的;v.应用,适用
参考例句:
  • She plans to take a course in applied linguistics.她打算学习应用语言学课程。
  • This cream is best applied to the face at night.这种乳霜最好晚上擦脸用。
122 noxious zHOxB     
adj.有害的,有毒的;使道德败坏的,讨厌的
参考例句:
  • Heavy industry pollutes our rivers with noxious chemicals.重工业产生的有毒化学品会污染我们的河流。
  • Many household products give off noxious fumes.很多家用产品散发有害气体。
123 apparently tMmyQ     
adv.显然地;表面上,似乎
参考例句:
  • An apparently blind alley leads suddenly into an open space.山穷水尽,豁然开朗。
  • He was apparently much surprised at the news.他对那个消息显然感到十分惊异。
124 imbibe Fy9yO     
v.喝,饮;吸入,吸收
参考例句:
  • Plants imbibe nourishment usually through their leaves and roots.植物通常经过叶和根吸收养分。
  • I always imbibe fresh air in the woods.我经常在树林里呼吸新鲜空气。
125 imbibed fc2ca43ab5401c1fa27faa9c098ccc0d     
v.吸收( imbibe的过去式和过去分词 );喝;吸取;吸气
参考例句:
  • They imbibed the local cider before walking home to dinner. 他们在走回家吃饭之前喝了本地的苹果酒。 来自《简明英汉词典》
  • Hester Prynne imbibed this spirit. 海丝特 - 白兰汲取了这一精神。 来自英汉文学 - 红字
126 distinctive Es5xr     
adj.特别的,有特色的,与众不同的
参考例句:
  • She has a very distinctive way of walking.她走路的样子与别人很不相同。
  • This bird has several distinctive features.这个鸟具有几种突出的特征。
127 memorable K2XyQ     
adj.值得回忆的,难忘的,特别的,显著的
参考例句:
  • This was indeed the most memorable day of my life.这的确是我一生中最值得怀念的日子。
  • The veteran soldier has fought many memorable battles.这个老兵参加过许多难忘的战斗。
128 investigation MRKzq     
n.调查,调查研究
参考例句:
  • In an investigation,a new fact became known, which told against him.在调查中新发现了一件对他不利的事实。
  • He drew the conclusion by building on his own investigation.他根据自己的调查研究作出结论。
129 procuring 1d7f440d0ca1006a2578d7800f8213b2     
v.(努力)取得, (设法)获得( procure的现在分词 );拉皮条
参考例句:
  • He was accused of procuring women for his business associates. 他被指控为其生意合伙人招妓。 来自辞典例句
  • She had particular pleasure, in procuring him the proper invitation. 她特别高兴为他争得这份体面的邀请。 来自辞典例句
130 surmised b42dd4710fe89732a842341fc04537f6     
v.臆测,推断( surmise的过去式和过去分词 );揣测;猜想
参考例句:
  • From the looks on their faces, I surmised that they had had an argument. 看他们的脸色,我猜想他们之间发生了争执。
  • From his letter I surmised that he was unhappy. 我从他的信中推测他并不快乐。 来自《简明英汉词典》
131 remains 1kMzTy     
n.剩余物,残留物;遗体,遗迹
参考例句:
  • He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
  • The remains of the meal were fed to the dog.残羹剩饭喂狗了。
132 memoir O7Hz7     
n.[pl.]回忆录,自传;记事录
参考例句:
  • He has just published a memoir in honour of his captain.他刚刚出了一本传记来纪念他的队长。
  • In her memoir,the actress wrote about the bittersweet memories of her first love.在那个女演员的自传中,她写到了自己苦乐掺半的初恋。
133 memoirs f752e432fe1fefb99ab15f6983cd506c     
n.回忆录;回忆录传( mem,自oir的名词复数)
参考例句:
  • Her memoirs were ghostwritten. 她的回忆录是由别人代写的。
  • I watched a trailer for the screenplay of his memoirs. 我看过以他的回忆录改编成电影的预告片。 来自《简明英汉词典》
134 combustion 4qKzS     
n.燃烧;氧化;骚动
参考例句:
  • We might be tempted to think of combustion.我们也许会联想到氧化。
  • The smoke formed by their combustion is negligible.由它燃烧所生成的烟是可忽略的。
135 conjecture 3p8z4     
n./v.推测,猜测
参考例句:
  • She felt it no use to conjecture his motives.她觉得猜想他的动机是没有用的。
  • This conjecture is not supported by any real evidence.这种推测未被任何确切的证据所证实。
136 imbibing 1ad249b3b90d0413873a959aad2aa991     
v.吸收( imbibe的现在分词 );喝;吸取;吸气
参考例句:
  • It was not long before the imbibing began to tell. 很快,喝酒喝得有效果了。 来自英汉文学 - 嘉莉妹妹
  • The soil expands upon imbibing water. 土壤会由于吸水而膨胀。 来自辞典例句
137 overloaded Tmqz48     
a.超载的,超负荷的
参考例句:
  • He's overloaded with responsibilities. 他担负的责任过多。
  • She has overloaded her schedule with work, study, and family responsibilities. 她的日程表上排满了工作、学习、家务等,使自己负担过重。
138 inverted 184401f335d6b8661e04dfea47b9dcd5     
adj.反向的,倒转的v.使倒置,使反转( invert的过去式和过去分词 )
参考例句:
  • Only direct speech should go inside inverted commas. 只有直接引语应放在引号内。
  • Inverted flight is an acrobatic manoeuvre of the plane. 倒飞是飞机的一种特技动作。 来自《简明英汉词典》
139 vessel 4L1zi     
n.船舶;容器,器皿;管,导管,血管
参考例句:
  • The vessel is fully loaded with cargo for Shanghai.这艘船满载货物驶往上海。
  • You should put the water into a vessel.你应该把水装入容器中。
140 inconvenient m4hy5     
adj.不方便的,令人感到麻烦的
参考例句:
  • You have come at a very inconvenient time.你来得最不适时。
  • Will it be inconvenient for him to attend that meeting?他参加那次会议会不方便吗?
141 aromatic lv9z8     
adj.芳香的,有香味的
参考例句:
  • It has an agreeable aromatic smell.它有一种好闻的香味。
  • It is light,fruity aromatic and a perfect choice for ending a meal.它是口感轻淡,圆润,芳香的,用于结束一顿饭完美的选择。
142 spinach Dhuzr5     
n.菠菜
参考例句:
  • Eating spinach is supposed to make you strong.据说吃菠菜能使人强壮。
  • You should eat such vegetables as carrot,celery and spinach.你应该吃胡萝卜、芹菜和菠菜这类的蔬菜。
143 distillation vsexs     
n.蒸馏,蒸馏法
参考例句:
  • The discovery of distillation is usually accredited to the Arabs of the 11th century.通常认为,蒸馏法是阿拉伯人在11世纪发明的。
  • The oil is distilled from the berries of this small tree.油是从这种小树的浆果中提炼出来的。
144 accurately oJHyf     
adv.准确地,精确地
参考例句:
  • It is hard to hit the ball accurately.准确地击中球很难。
  • Now scientists can forecast the weather accurately.现在科学家们能准确地预报天气。
145 complement ZbTyZ     
n.补足物,船上的定员;补语;vt.补充,补足
参考例句:
  • The two suggestions complement each other.这两条建议相互补充。
  • They oppose each other also complement each other.它们相辅相成。
146 extinction sPwzP     
n.熄灭,消亡,消灭,灭绝,绝种
参考例句:
  • The plant is now in danger of extinction.这种植物现在有绝种的危险。
  • The island's way of life is doomed to extinction.这个岛上的生活方式注定要消失。
147 rendering oV5xD     
n.表现,描写
参考例句:
  • She gave a splendid rendering of Beethoven's piano sonata.她精彩地演奏了贝多芬的钢琴奏鸣曲。
  • His narrative is a super rendering of dialect speech and idiom.他的叙述是方言和土语最成功的运用。
148 wholesome Uowyz     
adj.适合;卫生的;有益健康的;显示身心健康的
参考例句:
  • In actual fact the things I like doing are mostly wholesome.实际上我喜欢做的事大都是有助于增进身体健康的。
  • It is not wholesome to eat without washing your hands.不洗手吃饭是不卫生的。
149 agitation TN0zi     
n.搅动;搅拌;鼓动,煽动
参考例句:
  • Small shopkeepers carried on a long agitation against the big department stores.小店主们长期以来一直在煽动人们反对大型百货商店。
  • These materials require constant agitation to keep them in suspension.这些药剂要经常搅动以保持悬浮状态。
150 putrid P04zD     
adj.腐臭的;有毒的;已腐烂的;卑劣的
参考例句:
  • To eat putrid food is liable to get sick.吃了腐败的食物容易生病。
  • A putrid smell drove us from the room.一股腐臭的气味迫使我们离开这房间。
151 aquatic mvXzk     
adj.水生的,水栖的
参考例句:
  • Aquatic sports include swimming and rowing.水上运动包括游泳和划船。
  • We visited an aquatic city in Italy.我们在意大利访问过一个水上城市。
152 residual SWcxl     
adj.复播复映追加时间;存留下来的,剩余的
参考例句:
  • There are still a few residual problems with the computer program.电脑程序还有一些残留问题。
  • The resulting residual chromatism is known as secondary spectrum.所得到的剩余色差叫做二次光谱。
153 turbid tm6wY     
adj.混浊的,泥水的,浓的
参考例句:
  • He found himself content to watch idly the sluggish flow of the turbid stream.他心安理得地懒洋洋地望着混浊的河水缓缓流着。
  • The lake's water is turbid.这个湖里的水混浊。
154 acting czRzoc     
n.演戏,行为,假装;adj.代理的,临时的,演出用的
参考例句:
  • Ignore her,she's just acting.别理她,她只是假装的。
  • During the seventies,her acting career was in eclipse.在七十年代,她的表演生涯黯然失色。
155 isolating 44778bf8913bd1ed228a8571456b945b     
adj.孤立的,绝缘的v.使隔离( isolate的现在分词 );将…剔出(以便看清和单独处理);使(某物质、细胞等)分离;使离析
参考例句:
  • Colour filters are not very effective in isolating narrow spectral bands. 一些滤色片不能很有效地分离狭窄的光谱带。 来自辞典例句
  • This became known as the streak method for isolating bacteria. 这个方法以后就称为分离细菌的划线法。 来自辞典例句
156 diminution 2l9zc     
n.减少;变小
参考例句:
  • They hope for a small diminution in taxes.他们希望捐税能稍有减少。
  • He experienced no diminution of his physical strength.他并未感觉体力衰落。
157 devours b540beb8d5eec2b2213f0a7074b7692f     
吞没( devour的第三人称单数 ); 耗尽; 津津有味地看; 狼吞虎咽地吃光
参考例句:
  • If anyone tries to harm them, fire comes from their mouths and devours their enemies. 若有人想要害他们,就有火从他们口中出来,烧灭仇敌。
  • It eats away parts of his skin; death's firstborn devours his limbs. 他本身的肢体要被吞吃,死亡的长子要吞吃他的肢体。
158 considerably 0YWyQ     
adv.极大地;相当大地;在很大程度上
参考例句:
  • The economic situation has changed considerably.经济形势已发生了相当大的变化。
  • The gap has narrowed considerably.分歧大大缩小了。
159 distinguished wu9z3v     
adj.卓越的,杰出的,著名的
参考例句:
  • Elephants are distinguished from other animals by their long noses.大象以其长长的鼻子显示出与其他动物的不同。
  • A banquet was given in honor of the distinguished guests.宴会是为了向贵宾们致敬而举行的。
160 quantitative TCpyg     
adj.数量的,定量的
参考例句:
  • He said it was only a quantitative difference.他说这仅仅是数量上的差别。
  • We need to do some quantitative analysis of the drugs.我们对药物要进行定量分析。
161 fumes lsYz3Q     
n.(强烈而刺激的)气味,气体
参考例句:
  • The health of our children is being endangered by exhaust fumes. 我们孩子们的健康正受到排放出的废气的损害。
  • Exhaust fumes are bad for your health. 废气对健康有害。
162 charcoal prgzJ     
n.炭,木炭,生物炭
参考例句:
  • We need to get some more charcoal for the barbecue.我们烧烤需要更多的碳。
  • Charcoal is used to filter water.木炭是用来过滤水的。
163 determined duszmP     
adj.坚定的;有决心的
参考例句:
  • I have determined on going to Tibet after graduation.我已决定毕业后去西藏。
  • He determined to view the rooms behind the office.他决定查看一下办公室后面的房间。
164 incapable w9ZxK     
adj.无能力的,不能做某事的
参考例句:
  • He would be incapable of committing such a cruel deed.他不会做出这么残忍的事。
  • Computers are incapable of creative thought.计算机不会创造性地思维。
165 remarkably EkPzTW     
ad.不同寻常地,相当地
参考例句:
  • I thought she was remarkably restrained in the circumstances. 我认为她在那种情况下非常克制。
  • He made a remarkably swift recovery. 他康复得相当快。
166 metallic LCuxO     
adj.金属的;金属制的;含金属的;产金属的;像金属的
参考例句:
  • A sharp metallic note coming from the outside frightened me.外面传来尖锐铿锵的声音吓了我一跳。
  • He picked up a metallic ring last night.昨夜他捡了一个金属戒指。
167 copper HZXyU     
n.铜;铜币;铜器;adj.铜(制)的;(紫)铜色的
参考例句:
  • The students are asked to prove the purity of copper.要求学生们检验铜的纯度。
  • Copper is a good medium for the conduction of heat and electricity.铜是热和电的良导体。
168 dense aONzX     
a.密集的,稠密的,浓密的;密度大的
参考例句:
  • The general ambushed his troops in the dense woods. 将军把部队埋伏在浓密的树林里。
  • The path was completely covered by the dense foliage. 小路被树叶厚厚地盖了一层。
169 marine 77Izo     
adj.海的;海生的;航海的;海事的;n.水兵
参考例句:
  • Marine creatures are those which live in the sea. 海洋生物是生存在海里的生物。
  • When the war broke out,he volunteered for the Marine Corps.战争爆发时,他自愿参加了海军陆战队。
170 hissing hissing     
n. 发嘶嘶声, 蔑视 动词hiss的现在分词形式
参考例句:
  • The steam escaped with a loud hissing noise. 蒸汽大声地嘶嘶冒了出来。
  • His ears were still hissing with the rustle of the leaves. 他耳朵里还听得萨萨萨的声音和屑索屑索的怪声。 来自汉英文学 - 春蚕
171 volatile tLQzQ     
adj.反复无常的,挥发性的,稍纵即逝的,脾气火爆的;n.挥发性物质
参考例句:
  • With the markets being so volatile,investments are at great risk.由于市场那么变化不定,投资冒着很大的风险。
  • His character was weak and volatile.他这个人意志薄弱,喜怒无常。
172 procured 493ee52a2e975a52c94933bb12ecc52b     
v.(努力)取得, (设法)获得( procure的过去式和过去分词 );拉皮条
参考例句:
  • These cars are to be procured through open tender. 这些汽车要用公开招标的办法购买。 来自《现代汉英综合大词典》
  • A friend procured a position in the bank for my big brother. 一位朋友为我哥哥谋得了一个银行的职位。 来自《用法词典》
173 procure A1GzN     
vt.获得,取得,促成;vi.拉皮条
参考例句:
  • Can you procure some specimens for me?你能替我弄到一些标本吗?
  • I'll try my best to procure you that original French novel.我将尽全力给你搞到那本原版法国小说。
174 favourable favourable     
adj.赞成的,称赞的,有利的,良好的,顺利的
参考例句:
  • The company will lend you money on very favourable terms.这家公司将以非常优惠的条件借钱给你。
  • We found that most people are favourable to the idea.我们发现大多数人同意这个意见。
175 slaked 471a11f43e136d5e6058d2a4ba9c1442     
v.满足( slake的过去式和过去分词 )
参考例句:
  • I slaked my thirst with three cans of Coke. 我喝了3罐可乐解渴。 来自辞典例句
  • We returned to the barn and slaked our thirst with tea. 我们回到谷仓,饮茶解渴。 来自辞典例句
176 soluble LrMya     
adj.可溶的;可以解决的
参考例句:
  • These tablets are soluble in water.这些药片可在水中溶解。
  • Camphor is soluble in alcohol.樟脑在酒精中可以溶化。
177 subsided 1bda21cef31764468020a8c83598cc0d     
v.(土地)下陷(因在地下采矿)( subside的过去式和过去分词 );减弱;下降至较低或正常水平;一下子坐在椅子等上
参考例句:
  • After the heavy rains part of the road subsided. 大雨过后,部分公路塌陷了。 来自《简明英汉词典》
  • By evening the storm had subsided and all was quiet again. 傍晚, 暴风雨已经过去,四周开始沉寂下来。 来自《现代汉英综合大词典》
178 ascends 70c31d4ff86cb70873a6a196fadac6b8     
v.上升,攀登( ascend的第三人称单数 )
参考例句:
  • The azygos vein ascends in the right paravertebral gutter. 奇静脉在右侧脊柱旁沟内上升。 来自辞典例句
  • The mortality curve ascends gradually to a plateau at age 65. 死亡曲线逐渐上升,到65岁时成平稳状态。 来自辞典例句
179 narration tFvxS     
n.讲述,叙述;故事;记叙体
参考例句:
  • The richness of his novel comes from his narration of it.他小说的丰富多采得益于他的叙述。
  • Narration should become a basic approach to preschool education.叙事应是幼儿教育的基本途径。
180 obstructed 5b709055bfd182f94d70e3e16debb3a4     
阻塞( obstruct的过去式和过去分词 ); 堵塞; 阻碍; 阻止
参考例句:
  • Tall trees obstructed his view of the road. 有大树挡着,他看不到道路。
  • The Irish and Bristol Channels were closed or grievously obstructed. 爱尔兰海峡和布里斯托尔海峡或遭受封锁,或受到了严重阻碍。
181 conjectures 8334e6a27f5847550b061d064fa92c00     
推测,猜想( conjecture的名词复数 )
参考例句:
  • That's weighing remote military conjectures against the certain deaths of innocent people. 那不过是牵强附会的军事假设,而现在的事实却是无辜者正在惨遭杀害,这怎能同日而语!
  • I was right in my conjectures. 我所猜测的都应验了。
182 relinquish 4Bazt     
v.放弃,撤回,让与,放手
参考例句:
  • He was forced to relinquish control of the company.他被迫放弃公司的掌控权。
  • They will never voluntarily relinquish their independence.他们绝对不会自动放弃独立。
183 decomposed d6dafa7f02e02b23fd957d01ced03499     
已分解的,已腐烂的
参考例句:
  • A liquid is decomposed when an electric current passes through it. 当电流通过时,液体就分解。
  • Water can be resolved [decomposed] into hydrogen and oxygen. 水可分解为氢和氧。
184 exhaled 8e9b6351819daaa316dd7ab045d3176d     
v.呼出,发散出( exhale的过去式和过去分词 );吐出(肺中的空气、烟等),呼气
参考例句:
  • He sat back and exhaled deeply. 他仰坐着深深地呼气。
  • He stamped his feet and exhaled a long, white breath. 跺了跺脚,他吐了口长气,很长很白。 来自汉英文学 - 骆驼祥子
185 apprehensive WNkyw     
adj.担心的,恐惧的,善于领会的
参考例句:
  • She was deeply apprehensive about her future.她对未来感到非常担心。
  • He was rather apprehensive of failure.他相当害怕失败。
186 extenuation e9b8ed745af478408c950e9156f754b0     
n.减轻罪孽的借口;酌情减轻;细
参考例句:
  • Miss Glover could allow no extenuation of her crime. 格洛弗小姐是不允许袒护罪过的。 来自辞典例句
  • It was a comfort to him, this extenuation. 这借口对他是种安慰。 来自辞典例句
187 chimerical 4VIyv     
adj.荒诞不经的,梦幻的
参考例句:
  • His Utopia is not a chimerical commonwealth but a practical improvement on what already exists.他的乌托邦不是空想的联邦,而是对那些已经存在的联邦事实上的改进。
  • Most interpret the information from the victims as chimerical thinking.大多数来自于受害者的解释是被当作空想。
188 derived 6cddb7353e699051a384686b6b3ff1e2     
vi.起源;由来;衍生;导出v.得到( derive的过去式和过去分词 );(从…中)得到获得;源于;(从…中)提取
参考例句:
  • Many English words are derived from Latin and Greek. 英语很多词源出于拉丁文和希腊文。 来自《简明英汉词典》
  • He derived his enthusiasm for literature from his father. 他对文学的爱好是受他父亲的影响。 来自《简明英汉词典》
189 queries 5da7eb4247add5dbd5776c9c0b38460a     
n.问题( query的名词复数 );疑问;询问;问号v.质疑,对…表示疑问( query的第三人称单数 );询问
参考例句:
  • Our assistants will be happy to answer your queries. 我们的助理很乐意回答诸位的问题。
  • Her queries were rhetorical,and best ignored. 她的质问只不过是说说而已,最好不予理睬。 来自《简明英汉词典》
190 incompatible y8oxu     
adj.不相容的,不协调的,不相配的
参考例句:
  • His plan is incompatible with my intent.他的计划与我的意图不相符。
  • Speed and safety are not necessarily incompatible.速度和安全未必不相容。
191 perseverance oMaxH     
n.坚持不懈,不屈不挠
参考例句:
  • It may take some perseverance to find the right people.要找到合适的人也许需要有点锲而不舍的精神。
  • Perseverance leads to success.有恒心就能胜利。
192 investigations 02de25420938593f7db7bd4052010b32     
(正式的)调查( investigation的名词复数 ); 侦查; 科学研究; 学术研究
参考例句:
  • His investigations were intensive and thorough but revealed nothing. 他进行了深入彻底的调查,但没有发现什么。
  • He often sent them out to make investigations. 他常常派他们出去作调查。
193 reins 370afc7786679703b82ccfca58610c98     
感情,激情; 缰( rein的名词复数 ); 控制手段; 掌管; (成人带着幼儿走路以防其走失时用的)保护带
参考例句:
  • She pulled gently on the reins. 她轻轻地拉着缰绳。
  • The government has imposed strict reins on the import of luxury goods. 政府对奢侈品的进口有严格的控制手段。
194 ambling 83ee3bf75d76f7573f42fe45eaa3d174     
v.(马)缓行( amble的现在分词 );从容地走,漫步
参考例句:
  • At that moment the tiger commenced ambling towards his victim. 就在这时,老虎开始缓步向它的猎物走去。 来自辞典例句
  • Implied meaning: drinking, ambling, the people who make golf all relatively succeed. 寓意:喝酒,赌博,打高尔夫的人都比较成功。 来自互联网
195 utterly ZfpzM1     
adv.完全地,绝对地
参考例句:
  • Utterly devoted to the people,he gave his life in saving his patients.他忠于人民,把毕生精力用于挽救患者的生命。
  • I was utterly ravished by the way she smiled.她的微笑使我完全陶醉了。
196 quagmire StDy3     
n.沼地
参考例句:
  • On their way was a quagmire which was difficult to get over.路上他俩遇到了—个泥坑,很难过得去。
  • Rain had turned the grass into a quagmire.大雨使草地变得一片泥泞。
197 speculation 9vGwe     
n.思索,沉思;猜测;投机
参考例句:
  • Her mind is occupied with speculation.她的头脑忙于思考。
  • There is widespread speculation that he is going to resign.人们普遍推测他要辞职。
198 speculations da17a00acfa088f5ac0adab7a30990eb     
n.投机买卖( speculation的名词复数 );思考;投机活动;推断
参考例句:
  • Your speculations were all quite close to the truth. 你的揣测都很接近于事实。 来自《现代英汉综合大词典》
  • This possibility gives rise to interesting speculations. 这种可能性引起了有趣的推测。 来自《用法词典》
199 dedicated duHzy2     
adj.一心一意的;献身的;热诚的
参考例句:
  • He dedicated his life to the cause of education.他献身于教育事业。
  • His whole energies are dedicated to improve the design.他的全部精力都放在改进这项设计上了。
200 prerogatives e2f058787466d6bb48040c6f4321ae53     
n.权利( prerogative的名词复数 );特权;大主教法庭;总督委任组成的法庭
参考例句:
  • The tsar protected his personal prerogatives. 沙皇维护了自己的私人特权。 来自《简明英汉词典》
  • Congressmen may be reluctant to vote for legislation that infringes the traditional prerogatives of the states. 美国国会议员可能不情愿投票拥护侵犯各州传统特权的立法。 来自英汉非文学 - 环境法 - 环境法
201 delightfully f0fe7d605b75a4c00aae2f25714e3131     
大喜,欣然
参考例句:
  • The room is delightfully appointed. 这房子的设备令人舒适愉快。 来自《现代汉英综合大词典》
  • The evening is delightfully cool. 晚间凉爽宜人。 来自《现代汉英综合大词典》
202 providence 8tdyh     
n.深谋远虑,天道,天意;远见;节约;上帝
参考例句:
  • It is tempting Providence to go in that old boat.乘那艘旧船前往是冒大险。
  • To act as you have done is to fly in the face of Providence.照你的所作所为那样去行事,是违背上帝的意志的。
203 testimony zpbwO     
n.证词;见证,证明
参考例句:
  • The testimony given by him is dubious.他所作的证据是可疑的。
  • He was called in to bear testimony to what the police officer said.他被传入为警官所说的话作证。
204 impartiality 5b49bb7ab0b3222fd7bf263721e2169d     
n. 公平, 无私, 不偏
参考例句:
  • He shows impartiality and detachment. 他表现得不偏不倚,超然事外。
  • Impartiality is essential to a judge. 公平是当法官所必需的。
205 concealed 0v3zxG     
a.隐藏的,隐蔽的
参考例句:
  • The paintings were concealed beneath a thick layer of plaster. 那些画被隐藏在厚厚的灰泥层下面。
  • I think he had a gun concealed about his person. 我认为他当时身上藏有一支枪。
206 purely 8Sqxf     
adv.纯粹地,完全地
参考例句:
  • I helped him purely and simply out of friendship.我帮他纯粹是出于友情。
  • This disproves the theory that children are purely imitative.这证明认为儿童只会单纯地模仿的理论是站不住脚的。
207 purgatory BS7zE     
n.炼狱;苦难;adj.净化的,清洗的
参考例句:
  • Every step of the last three miles was purgatory.最后3英里时每一步都像是受罪。
  • Marriage,with peace,is this world's paradise;with strife,this world's purgatory.和谐的婚姻是尘世的乐园,不和谐的婚姻则是人生的炼狱。
208 vitriolic wHnyP     
adj.硫酸的,尖刻的
参考例句:
  • The newspaper launched a vitriolic attack on the president.这家报纸对总统发起了一场恶意的攻击。
  • Vitriolic impurity is contained normally in the sewage that vitriolic factory discharges.硫酸厂排放的污水中通常含有硫酸杂质。
209 suffocating suffocating     
a.使人窒息的
参考例句:
  • After a few weeks with her parents, she felt she was suffocating.和父母呆了几个星期后,她感到自己毫无自由。
  • That's better. I was suffocating in that cell of a room.这样好些了,我刚才在那个小房间里快闷死了。
210 plentifully f6b211d13287486e1bf5cd496d4f9f39     
adv. 许多地,丰饶地
参考例句:
  • The visitors were plentifully supplied with food and drink. 给来宾准备了丰富的食物和饮料。
  • The oil flowed plentifully at first, but soon ran out. 起初石油大量涌出,但很快就枯竭了。
211 solubility 2e0307f57c2d05361250f9ce1b56c122     
n.溶解度;可解决性;溶度
参考例句:
  • Elasticity, solubility, inflammability are paradigm cases of dispositions in natural objects. 伸缩性、可缩性、易燃性是天然物体倾向性的范例。 来自辞典例句
  • Solubility products are sometimes known with similar accuracy. 溶度积时有时也具有同样的准确度。 来自辞典例句
212 philosophically 5b1e7592f40fddd38186dac7bc43c6e0     
adv.哲学上;富有哲理性地;贤明地;冷静地
参考例句:
  • He added philosophically that one should adapt oneself to the changed conditions. 他富于哲理地补充说,一个人应该适应变化了的情况。 来自《简明英汉词典》
  • Harry took his rejection philosophically. 哈里达观地看待自己被拒的事。 来自《简明英汉词典》
213 synthetically a15ece361e9a5289112dfbb9319bf772     
adv. 综合地,合成地
参考例句:
  • The time sequence model synthetically reflects trends of groundwater level. 总体来说,季节性时序模型的模拟和预测精度较高。
  • You can't do It'synthetically, by just flying around and dropping in. 你不能仅靠坐着飞机到处蜻蜓点水地看看就得出一个综合印象。
214 celebrated iwLzpz     
adj.有名的,声誉卓著的
参考例句:
  • He was soon one of the most celebrated young painters in England.不久他就成了英格兰最负盛名的年轻画家之一。
  • The celebrated violinist was mobbed by the audience.观众团团围住了这位著名的小提琴演奏家。
215 acumen qVgzn     
n.敏锐,聪明
参考例句:
  • She has considerable business acumen.她的经营能力绝非一般。
  • His business acumen has made his very successful.他的商业头脑使他很成功。
216 analytically HL1yS     
adv.有分析地,解析地
参考例句:
  • The final requirement,'significant environmental impact", is analytically more difficult. 最后一个规定“重大的环境影响”,分析起来是比较困难的。 来自英汉非文学 - 环境法 - 环境法
  • The overwhelming majority of nonlinear differential equations are not soluble analytically. 绝大多数非线性微分方程是不能用解析方法求解的。
217 ingenuously 70b75fa07a553aa716ee077a3105c751     
adv.率直地,正直地
参考例句:
  • Voldemort stared at him ingenuously. The man MUST have lost his marbles. 魔王愕然向对方望过去。这家伙绝对疯了。 来自互联网
218 frankly fsXzcf     
adv.坦白地,直率地;坦率地说
参考例句:
  • To speak frankly, I don't like the idea at all.老实说,我一点也不赞成这个主意。
  • Frankly speaking, I'm not opposed to reform.坦率地说,我不反对改革。
219 obtrude M0Sy6     
v.闯入;侵入;打扰
参考例句:
  • I'm sorry to obtrude on you at such a time.我很抱歉在这个时候打扰你。
  • You had better not obtrude your opinions on others.你最好不要强迫别人接受你的意见。
220 hesitation tdsz5     
n.犹豫,踌躇
参考例句:
  • After a long hesitation, he told the truth at last.踌躇了半天,他终于直说了。
  • There was a certain hesitation in her manner.她的态度有些犹豫不决。
221 biases a1eb9034f18cae637caab5279cc70546     
偏见( bias的名词复数 ); 偏爱; 特殊能力; 斜纹
参考例句:
  • Stereotypes represent designer or researcher biases and assumptions, rather than factual data. 它代表设计师或者研究者的偏见和假设,而不是实际的数据。 来自About Face 3交互设计精髓
  • The net effect of biases on international comparisons is easily summarized. 偏差对国际比较的基本影响容易概括。
222 judgments 2a483d435ecb48acb69a6f4c4dd1a836     
判断( judgment的名词复数 ); 鉴定; 评价; 审判
参考例句:
  • A peculiar austerity marked his judgments of modern life. 他对现代生活的批评带着一种特殊的苛刻。
  • He is swift with his judgments. 他判断迅速。
223 persuasions 7acb1d2602a56439ada9ab1a54954d31     
n.劝说,说服(力)( persuasion的名词复数 );信仰
参考例句:
  • To obtain more advertisting it needed readers of all political persuasions. 为获得更多的广告,它需要迎合各种政治见解的读者。 来自辞典例句
  • She lingered, and resisted my persuasions to departure a tiresome while. 她踌躇不去,我好说歹说地劝她走,她就是不听。 来自辞典例句
224 entangled e3d30c3c857155b7a602a9ac53ade890     
adj.卷入的;陷入的;被缠住的;缠在一起的v.使某人(某物/自己)缠绕,纠缠于(某物中),使某人(自己)陷入(困难或复杂的环境中)( entangle的过去式和过去分词 )
参考例句:
  • The bird had become entangled in the wire netting. 那只小鸟被铁丝网缠住了。
  • Some military observers fear the US could get entangled in another war. 一些军事观察家担心美国会卷入另一场战争。 来自《简明英汉词典》
225 helping 2rGzDc     
n.食物的一份&adj.帮助人的,辅助的
参考例句:
  • The poor children regularly pony up for a second helping of my hamburger. 那些可怜的孩子们总是要求我把我的汉堡包再给他们一份。
  • By doing this, they may at times be helping to restore competition. 这样一来, 他在某些时候,有助于竞争的加强。
226 evading 6af7bd759f5505efaee3e9c7803918e5     
逃避( evade的现在分词 ); 避开; 回避; 想不出
参考例句:
  • Segmentation of a project is one means of evading NEPA. 把某一工程进行分割,是回避《国家环境政策法》的一种手段。 来自英汉非文学 - 环境法 - 环境法
  • Too many companies, she says, are evading the issue. 她说太多公司都在回避这个问题。
227 maxims aa76c066930d237742b409ad104a416f     
n.格言,座右铭( maxim的名词复数 )
参考例句:
  • Courts also draw freely on traditional maxims of construction. 法院也自由吸收传统的解释准则。 来自英汉非文学 - 行政法
  • There are variant formulations of some of the maxims. 有些准则有多种表达方式。 来自辞典例句
228 atmospherical 9d08570c388cd3e135ad749c5aeaf4ca     
adj.空气的,气压的
参考例句:
229 subservient WqByt     
adj.卑屈的,阿谀的
参考例句:
  • He was subservient and servile.他低声下气、卑躬屈膝。
  • It was horrible to have to be affable and subservient.不得不强作欢颜卖弄风骚,真是太可怕了。
230 ERECTED ERECTED     
adj. 直立的,竖立的,笔直的 vt. 使 ... 直立,建立
参考例句:
  • A monument to him was erected in St Paul's Cathedral. 在圣保罗大教堂为他修了一座纪念碑。
  • A monument was erected to the memory of that great scientist. 树立了一块纪念碑纪念那位伟大的科学家。
231 alacrity MfFyL     
n.敏捷,轻快,乐意
参考例句:
  • Although the man was very old,he still moved with alacrity.他虽然很老,动作仍很敏捷。
  • He accepted my invitation with alacrity.他欣然接受我的邀请。
232 vessels fc9307c2593b522954eadb3ee6c57480     
n.血管( vessel的名词复数 );船;容器;(具有特殊品质或接受特殊品质的)人
参考例句:
  • The river is navigable by vessels of up to 90 tons. 90 吨以下的船只可以从这条河通过。 来自《简明英汉词典》
  • All modern vessels of any size are fitted with radar installations. 所有现代化船只都有雷达装置。 来自《现代汉英综合大词典》
233 precipitate 1Sfz6     
adj.突如其来的;vt.使突然发生;n.沉淀物
参考例句:
  • I don't think we should make precipitate decisions.我认为我们不应该贸然作出决定。
  • The king was too precipitate in declaring war.国王在宣战一事上过于轻率。
234 specimen Xvtwm     
n.样本,标本
参考例句:
  • You'll need tweezers to hold up the specimen.你要用镊子来夹这标本。
  • This specimen is richly variegated in colour.这件标本上有很多颜色。
235 recollect eUOxl     
v.回忆,想起,记起,忆起,记得
参考例句:
  • He tried to recollect things and drown himself in them.他极力回想过去的事情而沉浸于回忆之中。
  • She could not recollect being there.她回想不起曾经到过那儿。
236 precisely zlWzUb     
adv.恰好,正好,精确地,细致地
参考例句:
  • It's precisely that sort of slick sales-talk that I mistrust.我不相信的正是那种油腔滑调的推销宣传。
  • The man adjusted very precisely.那个人调得很准。
237 astonishment VvjzR     
n.惊奇,惊异
参考例句:
  • They heard him give a loud shout of astonishment.他们听见他惊奇地大叫一声。
  • I was filled with astonishment at her strange action.我对她的奇怪举动不胜惊异。
238 forth Hzdz2     
adv.向前;向外,往外
参考例句:
  • The wind moved the trees gently back and forth.风吹得树轻轻地来回摇晃。
  • He gave forth a series of works in rapid succession.他很快连续发表了一系列的作品。
239 conjectured c62e90c2992df1143af0d33094f0d580     
推测,猜测,猜想( conjecture的过去式和过去分词 )
参考例句:
  • The old peasant conjectured that it would be an unusually cold winter. 那老汉推测冬天将会异常地寒冷。
  • The general conjectured that the enemy only had about five days' supply of food left. 将军推测敌人只剩下五天的粮食给养。
240 vivacity ZhBw3     
n.快活,活泼,精神充沛
参考例句:
  • Her charm resides in her vivacity.她的魅力存在于她的活泼。
  • He was charmed by her vivacity and high spirits.她的活泼与兴高采烈的情绪把他迷住了。
241 augment Uuozw     
vt.(使)增大,增加,增长,扩张
参考例句:
  • They hit upon another idea to augment their income.他们又想出一个增加收入的办法。
  • The government's first concern was to augment the army and auxiliary forces.政府首先关心的是增强军队和辅助的力量。
242 morbid u6qz3     
adj.病的;致病的;病态的;可怕的
参考例句:
  • Some people have a morbid fascination with crime.一些人对犯罪有一种病态的痴迷。
  • It's morbid to dwell on cemeteries and such like.不厌其烦地谈论墓地以及诸如此类的事是一种病态。
243 exhausted 7taz4r     
adj.极其疲惫的,精疲力尽的
参考例句:
  • It was a long haul home and we arrived exhausted.搬运回家的这段路程特别长,到家时我们已筋疲力尽。
  • Jenny was exhausted by the hustle of city life.珍妮被城市生活的忙乱弄得筋疲力尽。
244 contradictory VpazV     
adj.反驳的,反对的,抗辩的;n.正反对,矛盾对立
参考例句:
  • The argument is internally contradictory.论据本身自相矛盾。
  • What he said was self-contradictory.他讲话前后不符。
245 corroded 77e49c02c5fb1fe2e59b1a771002f409     
已被腐蚀的
参考例句:
  • Rust has corroded the steel rails. 锈侵蚀了钢轨。
  • Jealousy corroded his character. 嫉妒损伤了他的人格。
246 recipient QA8zF     
a.接受的,感受性强的 n.接受者,感受者,容器
参考例句:
  • Please check that you have a valid email certificate for each recipient. 请检查是否对每个接收者都有有效的电子邮件证书。
  • Colombia is the biggest U . S aid recipient in Latin America. 哥伦比亚是美国在拉丁美洲最大的援助对象。
247 friable EisxX     
adj.易碎的
参考例句:
  • The friable boxes arrived intact.这些易碎的箱子完整无损地运到了。
  • The friable china survived the bumpy journey safe and sound.那批易碎的瓷器经过颠簸的旅途仍完好无损。
248 stony qu1wX     
adj.石头的,多石头的,冷酷的,无情的
参考例句:
  • The ground is too dry and stony.这块地太干,而且布满了石头。
  • He listened to her story with a stony expression.他带着冷漠的表情听她讲经历。
249 opaque jvhy1     
adj.不透光的;不反光的,不传导的;晦涩的
参考例句:
  • The windows are of opaque glass.这些窗户装着不透明玻璃。
  • Their intentions remained opaque.他们的意图仍然令人费解。
250 precipitated cd4c3f83abff4eafc2a6792d14e3895b     
v.(突如其来地)使发生( precipitate的过去式和过去分词 );促成;猛然摔下;使沉淀
参考例句:
  • His resignation precipitated a leadership crisis. 他的辞职立即引发了领导层的危机。
  • He lost his footing and was precipitated to the ground. 他失足摔倒在地上。 来自《简明英汉词典》
251 discursive LtExz     
adj.离题的,无层次的
参考例句:
  • His own toast was discursive and overlong,though rather touching.他自己的祝酒词虽然也颇为动人,但是比较松散而冗长。
  • They complained that my writing was becoming too discursive.他们抱怨我的文章变得太散漫。
252 constrained YvbzqU     
adj.束缚的,节制的
参考例句:
  • The evidence was so compelling that he felt constrained to accept it. 证据是那样的令人折服,他觉得不得不接受。
  • I feel constrained to write and ask for your forgiveness. 我不得不写信请你原谅。
253 respite BWaxa     
n.休息,中止,暂缓
参考例句:
  • She was interrogated without respite for twenty-four hours.她被不间断地审问了二十四小时。
  • Devaluation would only give the economy a brief respite.贬值只能让经济得到暂时的缓解。
254 promising BkQzsk     
adj.有希望的,有前途的
参考例句:
  • The results of the experiments are very promising.实验的结果充满了希望。
  • We're trying to bring along one or two promising young swimmers.我们正设法培养出一两名有前途的年轻游泳选手。
255 entreat soexj     
v.恳求,恳请
参考例句:
  • Charles Darnay felt it hopeless entreat him further,and his pride was touched besides.查尔斯-达尔内感到再恳求他已是枉然,自尊心也受到了伤害。
  • I entreat you to contribute generously to the building fund.我恳求您慷慨捐助建设基金。
256 oversights e777d188f279df70d89b1c8eda132ea7     
n.疏忽( oversight的名词复数 );忽略;失察;负责
参考例句:
  • He saw shocking oversights and inefficiencies that made the Separatist invasion possible. 他看出在首都遭到分裂势力入侵的背后是惊人的疏漏与低效。 来自互联网
  • Instead it means that the submitted code has no glaringly obvious oversights. 相反,它意味着所提交的代码没有突出的显而易见的疏忽或错漏。 来自互联网
257 premature FPfxV     
adj.比预期时间早的;不成熟的,仓促的
参考例句:
  • It is yet premature to predict the possible outcome of the dialogue.预言这次对话可能有什么结果为时尚早。
  • The premature baby is doing well.那个早产的婴儿很健康。
258 attachment POpy1     
n.附属物,附件;依恋;依附
参考例句:
  • She has a great attachment to her sister.她十分依恋她的姐姐。
  • She's on attachment to the Ministry of Defense.她现在隶属于国防部。
259 obstruction HRrzR     
n.阻塞,堵塞;障碍物
参考例句:
  • She was charged with obstruction of a police officer in the execution of his duty.她被指控妨碍警察执行任务。
  • The road was cleared from obstruction.那条路已被清除了障碍。
260 resentment 4sgyv     
n.怨愤,忿恨
参考例句:
  • All her feelings of resentment just came pouring out.她一股脑儿倾吐出所有的怨恨。
  • She cherished a deep resentment under the rose towards her employer.她暗中对她的雇主怀恨在心。
261 zealously c02c29296a52ac0a3d83dc431626fc33     
adv.热心地;热情地;积极地;狂热地
参考例句:
  • Of course the more unpleasant a duty was, the more zealously Miss Glover performed it. 格洛弗小姐越是对她的职责不满意,她越是去积极执行它。 来自辞典例句
  • A lawyer should represent a client zealously within the bounds of the law. 律师应在法律范围内热忱为当事人代理。 来自口语例句
262 logician 1ce64af885e87536cbdf996e79fdda02     
n.逻辑学家
参考例句:
  • Mister Wu Feibai is a famous Mohist and logician in Chinese modern and contemporary history. 伍非百先生是中国近、现代著名的墨学家和逻辑学家。 来自互联网
263 scrupulous 6sayH     
adj.审慎的,小心翼翼的,完全的,纯粹的
参考例句:
  • She is scrupulous to a degree.她非常谨慎。
  • Poets are not so scrupulous as you are.诗人并不像你那样顾虑多。
264 aptitude 0vPzn     
n.(学习方面的)才能,资质,天资
参考例句:
  • That student has an aptitude for mathematics.那个学生有数学方面的天赋。
  • As a child,he showed an aptitude for the piano.在孩提时代,他显露出对于钢琴的天赋。
265 narrates 700af7b03723e0e80ae386f04634402e     
v.故事( narrate的第三人称单数 )
参考例句:
  • It narrates the unconstitutional acts of James II. 它历数了詹姆斯二世的违法行为。 来自辞典例句
  • Chapter three narrates the economy activity which Jew return the Occident. 第三章讲述了犹太人重返西欧后的经济活动。 来自互联网
266 supplementary 0r6ws     
adj.补充的,附加的
参考例句:
  • There is a supplementary water supply in case the rain supply fails.万一主水源断了,我们另外有供水的地方。
  • A supplementary volume has been published containing the index.附有索引的增补卷已经出版。
267 mutual eFOxC     
adj.相互的,彼此的;共同的,共有的
参考例句:
  • We must pull together for mutual interest.我们必须为相互的利益而通力合作。
  • Mutual interests tied us together.相互的利害关系把我们联系在一起。
268 decanting ef954146b4df91c541cf862494e046d1     
n.滗析(手续)v.将(酒等)自瓶中倒入另一容器( decant的现在分词 )
参考例句:
  • It was exhausting work moving the heavy buckets, decanting the liquids. 搬动沉重的桶,滗出液体,这些都是使人精疲力竭的工作。 来自辞典例句
  • To purify, separate, or remove(ore, for example) by washing, decanting, and settling. 淘洗,淘选,淘析用清洗、倾析和沉淀的方法来提纯、分离或清除(例如,矿石) 来自互联网
269 possessed xuyyQ     
adj.疯狂的;拥有的,占有的
参考例句:
  • He flew out of the room like a man possessed.他像着了魔似地猛然冲出房门。
  • He behaved like someone possessed.他行为举止像是魔怔了。
270 diffused 5aa05ed088f24537ef05f482af006de0     
散布的,普及的,扩散的
参考例句:
  • A drop of milk diffused in the water. 一滴牛奶在水中扩散开来。
  • Gases and liquids diffused. 气体和液体慢慢混合了。
271 effete 5PUz4     
adj.无生产力的,虚弱的
参考例句:
  • People said the aristocracy was effete.人们说贵族阶级已是日薄西山了。
  • During the ages,Greek civilization declined and became effete.在中世纪期间,希腊文明开始衰落直至衰败。
272 commendably d701ea1880111628b1a1d1f5fbc55b71     
很好地
参考例句:
  • So, workflow management technology is create, and then develop commendably. 于是工作流管理技术应运而生,并且蓬勃发展起来。 来自互联网
  • Mr McCain is a commendably committed free-trader. 麦凯恩是一个标志明显的自由贸易主义者。 来自互联网
273 allege PfEyT     
vt.宣称,申述,主张,断言
参考例句:
  • The newspaper reporters allege that the man was murdered but they have given no proof.新闻记者们宣称这个男人是被谋杀的,但他们没提出证据。
  • Students occasionally allege illness as the reason for absence.学生时不时会称病缺课。
274 initiated 9cd5622f36ab9090359c3cf3ca4ddda3     
n. 创始人 adj. 新加入的 vt. 开始,创始,启蒙,介绍加入
参考例句:
  • He has not yet been thoroughly initiated into the mysteries of computers. 他对计算机的奥秘尚未入门。
  • The artist initiated the girl into the art world in France. 这个艺术家介绍这个女孩加入巴黎艺术界。
275 previously bkzzzC     
adv.以前,先前(地)
参考例句:
  • The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
  • Let me digress for a moment and explain what had happened previously.让我岔开一会儿,解释原先发生了什么。
276 chamber wnky9     
n.房间,寝室;会议厅;议院;会所
参考例句:
  • For many,the dentist's surgery remains a torture chamber.对许多人来说,牙医的治疗室一直是间受刑室。
  • The chamber was ablaze with light.会议厅里灯火辉煌。
277 eloquence 6mVyM     
n.雄辩;口才,修辞
参考例句:
  • I am afraid my eloquence did not avail against the facts.恐怕我的雄辩也无补于事实了。
  • The people were charmed by his eloquence.人们被他的口才迷住了。
278 astringency d420f59a2505f8f89d8c354fed45feee     
n.收敛性,严酷
参考例句:
  • The endosperm of the nut owes its marked degree of astringency. 坚果的胚乳由于存在丹宁,所以有显著的涩味。 来自辞典例句
  • The mountain cultivation, the fruit is mature when cannot remain the astringency. 高山栽培,果实成熟时不会残留涩味。 来自互联网
279 astringent re2yN     
adj.止血的,收缩的,涩的;n.收缩剂,止血剂
参考例句:
  • It has an astringent effect.这个有止血的作用。
  • Green persimmons are strongly astringent.绿柿子非常涩。
280 gastronomic f7c510a163e3bbb44af862c8a6f9bdb8     
adj.美食(烹饪)法的,烹任学的
参考例句:
  • The gastronomic restaurant is a feature of the hotel. 美食餐厅是这家饭店的一个特色。 来自互联网
  • The restaurant offers a special gastronomic menu. 这家餐馆备有一份特别的美食菜单。 来自互联网
281 fowls 4f8db97816f2d0cad386a79bb5c17ea4     
鸟( fowl的名词复数 ); 禽肉; 既不是这; 非驴非马
参考例句:
  • A great number of water fowls dwell on the island. 许多水鸟在岛上栖息。
  • We keep a few fowls and some goats. 我们养了几只鸡和一些山羊。
282 liking mpXzQ5     
n.爱好;嗜好;喜欢
参考例句:
  • The word palate also means taste or liking.Palate这个词也有“口味”或“嗜好”的意思。
  • I must admit I have no liking for exaggeration.我必须承认我不喜欢夸大其词。
283 perspicacity perspicacity     
n. 敏锐, 聪明, 洞察力
参考例句:
  • Perspicacity includes selective code, selective comparing and selective combining. 洞察力包括选择性编码、选择性比较、选择性联合。
  • He may own the perspicacity and persistence to catch and keep the most valuable thing. 他可能拥有洞察力和坚忍力,可以抓住和保有人生中最宝贵的东西。
284 plausible hBCyy     
adj.似真实的,似乎有理的,似乎可信的
参考例句:
  • His story sounded plausible.他说的那番话似乎是真实的。
  • Her story sounded perfectly plausible.她的说辞听起来言之有理。
285 bowels qxMzez     
n.肠,内脏,内部;肠( bowel的名词复数 );内部,最深处
参考例句:
  • Salts is a medicine that causes movements of the bowels. 泻盐是一种促使肠子运动的药物。 来自《简明英汉词典》
  • The cabins are in the bowels of the ship. 舱房设在船腹内。 来自《简明英汉词典》
286 detonation C9zy0     
n.爆炸;巨响
参考例句:
  • A fearful detonation burst forth on the barricade.街垒传来一阵骇人的爆炸声。
  • Within a few hundreds of microseconds,detonation is complete.在几百微秒之内,爆炸便完成了。
287 wholesomeness 832f51223dfde70650ea37eaeff56278     
卫生性
参考例句:
288 specimens 91fc365099a256001af897127174fcce     
n.样品( specimen的名词复数 );范例;(化验的)抽样;某种类型的人
参考例句:
  • Astronauts have brought back specimens of rock from the moon. 宇航员从月球带回了岩石标本。
  • The traveler brought back some specimens of the rocks from the mountains. 那位旅行者从山上带回了一些岩石标本。 来自《简明英汉词典》
289 situated JiYzBH     
adj.坐落在...的,处于某种境地的
参考例句:
  • The village is situated at the margin of a forest.村子位于森林的边缘。
  • She is awkwardly situated.她的处境困难。
290 sanguine dCOzF     
adj.充满希望的,乐观的,血红色的
参考例句:
  • He has a sanguine attitude to life.他对于人生有乐观的看法。
  • He is not very sanguine about our chances of success.他对我们成功的机会不太乐观。
291 grotto h5Byz     
n.洞穴
参考例句:
  • We reached a beautiful grotto,whose entrance was almost hiden by the vine.我们到达了一个美丽的洞穴,洞的进口几乎被藤蔓遮掩著。
  • Water trickles through an underground grotto.水沿着地下岩洞流淌。
292 interfered 71b7e795becf1adbddfab2cd6c5f0cff     
v.干预( interfere的过去式和过去分词 );调停;妨碍;干涉
参考例句:
  • Complete absorption in sports interfered with his studies. 专注于运动妨碍了他的学业。 来自《简明英汉词典》
  • I am not going to be interfered with. 我不想别人干扰我的事情。 来自《简明英汉词典》
293 prosecution uBWyL     
n.起诉,告发,检举,执行,经营
参考例句:
  • The Smiths brought a prosecution against the organizers.史密斯家对组织者们提出起诉。
  • He attempts to rebut the assertion made by the prosecution witness.他试图反驳原告方证人所作的断言。
294 stimulated Rhrz78     
a.刺激的
参考例句:
  • The exhibition has stimulated interest in her work. 展览增进了人们对她作品的兴趣。
  • The award has stimulated her into working still harder. 奖金促使她更加努力地工作。
295 controverted d56d1c6a2982010981fd64d70b34e79a     
v.争论,反驳,否定( controvert的过去式和过去分词 )
参考例句:
296 surmises 0de4d975cd99d9759cc345e7fb0890b6     
v.臆测,推断( surmise的第三人称单数 );揣测;猜想
参考例句:
  • The detective is completely correct in his surmises. 这个侦探所推测的完全正确。 来自《简明英汉词典》
  • As the reader probably surmises, a variety of interest tables exists. 正如读者可能推测的那样,存在着各种各样的利息表。 来自辞典例句
297 physiological aAvyK     
adj.生理学的,生理学上的
参考例句:
  • He bought a physiological book.他买了一本生理学方面的书。
  • Every individual has a physiological requirement for each nutrient.每个人对每种营养成分都有一种生理上的需要。
298 isolated bqmzTd     
adj.与世隔绝的
参考例句:
  • His bad behaviour was just an isolated incident. 他的不良行为只是个别事件。
  • Patients with the disease should be isolated. 这种病的患者应予以隔离。
299 corroborative bveze5     
adj.确证(性)的,确凿的
参考例句:
  • Is there any corroborative evidence for this theory? 是否有进一步说明问题的论据来支持这个理论?
  • They convicted the wrong man on the basis of a signed confession with no corroborative evidence. 凭一张有签名的认罪书而没有确凿的佐证,他们就错误地判了那人有罪。 来自《简明英汉词典》
300 inadequacy Zkpyl     
n.无法胜任,信心不足
参考例句:
  • the inadequacy of our resources 我们的资源的贫乏
  • The failure is due to the inadequacy of preparations. 这次失败是由于准备不足造成的。
301 query iS4xJ     
n.疑问,问号,质问;vt.询问,表示怀疑
参考例句:
  • I query very much whether it is wise to act so hastily.我真怀疑如此操之过急地行动是否明智。
  • They raised a query on his sincerity.他们对他是否真诚提出质疑。
302 partially yL7xm     
adv.部分地,从某些方面讲
参考例句:
  • The door was partially concealed by the drapes.门有一部分被门帘遮住了。
  • The police managed to restore calm and the curfew was partially lifted.警方设法恢复了平静,宵禁部分解除。
303 constituent bpxzK     
n.选民;成分,组分;adj.组成的,构成的
参考例句:
  • Sugar is the main constituent of candy.食糖是糖果的主要成分。
  • Fibre is a natural constituent of a healthy diet.纤维是健康饮食的天然组成部分。
304 inaccurate D9qx7     
adj.错误的,不正确的,不准确的
参考例句:
  • The book is both inaccurate and exaggerated.这本书不但不准确,而且夸大其词。
  • She never knows the right time because her watch is inaccurate.她从来不知道准确的时间因为她的表不准。
305 apprehended a58714d8af72af24c9ef953885c38a66     
逮捕,拘押( apprehend的过去式和过去分词 ); 理解
参考例句:
  • She apprehended the complicated law very quickly. 她很快理解了复杂的法律。
  • The police apprehended the criminal. 警察逮捕了罪犯。
306 apprehension bNayw     
n.理解,领悟;逮捕,拘捕;忧虑
参考例句:
  • There were still areas of doubt and her apprehension grew.有些地方仍然存疑,于是她越来越担心。
  • She is a girl of weak apprehension.她是一个理解力很差的女孩。
307 vibration nLDza     
n.颤动,振动;摆动
参考例句:
  • There is so much vibration on a ship that one cannot write.船上的震动大得使人无法书写。
  • The vibration of the window woke me up.窗子的震动把我惊醒了。
308 intensity 45Ixd     
n.强烈,剧烈;强度;烈度
参考例句:
  • I didn't realize the intensity of people's feelings on this issue.我没有意识到这一问题能引起群情激奋。
  • The strike is growing in intensity.罢工日益加剧。
309 brass DWbzI     
n.黄铜;黄铜器,铜管乐器
参考例句:
  • Many of the workers play in the factory's brass band.许多工人都在工厂铜管乐队中演奏。
  • Brass is formed by the fusion of copper and zinc.黄铜是通过铜和锌的熔合而成的。
310 contrived ivBzmO     
adj.不自然的,做作的;虚构的
参考例句:
  • There was nothing contrived or calculated about what he said.他说的话里没有任何蓄意捏造的成分。
  • The plot seems contrived.情节看起来不真实。
311 solely FwGwe     
adv.仅仅,唯一地
参考例句:
  • Success should not be measured solely by educational achievement.成功与否不应只用学业成绩来衡量。
  • The town depends almost solely on the tourist trade.这座城市几乎完全靠旅游业维持。
312 denser denser     
adj. 不易看透的, 密集的, 浓厚的, 愚钝的
参考例句:
  • The denser population necessitates closer consolidation both for internal and external action. 住得日益稠密的居民,对内和对外都不得不更紧密地团结起来。 来自英汉非文学 - 家庭、私有制和国家的起源
  • As Tito entered the neighbourhood of San Martino, he found the throng rather denser. 蒂托走近圣马丁教堂附近一带时,发现人群相当密集。
313 constable wppzG     
n.(英国)警察,警官
参考例句:
  • The constable conducted the suspect to the police station.警官把嫌疑犯带到派出所。
  • The constable kept his temper,and would not be provoked.那警察压制着自己的怒气,不肯冒起火来。
314 detriment zlHzx     
n.损害;损害物,造成损害的根源
参考例句:
  • Smoking is a detriment to one's health.吸烟危害健康。
  • His lack of education is a serious detriment to his career.他的未受教育对他的事业是一种严重的妨碍。
315 predilection 61Dz9     
n.偏好
参考例句:
  • He has a predilection for rich food.他偏好油腻的食物。
  • Charles has always had a predilection for red-haired women.查尔斯对红头发女人一直有偏爱。
316 engrossed 3t0zmb     
adj.全神贯注的
参考例句:
  • The student is engrossed in his book.这名学生正在专心致志地看书。
  • No one had ever been quite so engrossed in an evening paper.没人会对一份晚报如此全神贯注。
317 corruptions f937d102f5a7f58f5162a9ffb6987770     
n.堕落( corruption的名词复数 );腐化;腐败;贿赂
参考例句:
  • He stressed the corruptions of sin. 他强调了罪恶的腐朽。 来自互联网
318 bestowed 12e1d67c73811aa19bdfe3ae4a8c2c28     
赠给,授予( bestow的过去式和过去分词 )
参考例句:
  • It was a title bestowed upon him by the king. 那是国王赐给他的头衔。
  • He considered himself unworthy of the honour they had bestowed on him. 他认为自己不配得到大家赋予他的荣誉。
319 requisite 2W0xu     
adj.需要的,必不可少的;n.必需品
参考例句:
  • He hasn't got the requisite qualifications for the job.他不具备这工作所需的资格。
  • Food and air are requisite for life.食物和空气是生命的必需品。
320 ordained 629f6c8a1f6bf34be2caf3a3959a61f1     
v.任命(某人)为牧师( ordain的过去式和过去分词 );授予(某人)圣职;(上帝、法律等)命令;判定
参考例句:
  • He was ordained in 1984. 他在一九八四年被任命为牧师。 来自《简明英汉词典》
  • He was ordained priest. 他被任命为牧师。 来自辞典例句
321 doughty Jk5zg     
adj.勇猛的,坚强的
参考例句:
  • Most of successful men have the characteristics of contumacy and doughty.绝大多数成功人士都有共同的特质:脾气倔强,性格刚强。
  • The doughty old man battled his illness with fierce determination.坚强的老人用巨大毅力与疾病作斗争。
322 antagonist vwXzM     
n.敌人,对抗者,对手
参考例句:
  • His antagonist in the debate was quicker than he.在辩论中他的对手比他反应快。
  • The thing is to know the nature of your antagonist.要紧的是要了解你的对手的特性。
323 inexplicable tbCzf     
adj.无法解释的,难理解的
参考例句:
  • It is now inexplicable how that development was misinterpreted.当时对这一事态发展的错误理解究竟是怎么产生的,现在已经无法说清楚了。
  • There are many things which are inexplicable by science.有很多事科学还无法解释。
324 waning waning     
adj.(月亮)渐亏的,逐渐减弱或变小的n.月亏v.衰落( wane的现在分词 );(月)亏;变小;变暗淡
参考例句:
  • Her enthusiasm for the whole idea was waning rapidly. 她对整个想法的热情迅速冷淡了下来。
  • The day is waning and the road is ending. 日暮途穷。 来自《现代汉英综合大词典》
325 levity Q1uxA     
n.轻率,轻浮,不稳定,多变
参考例句:
  • His remarks injected a note of levity into the proceedings.他的话将一丝轻率带入了议事过程中。
  • At the time,Arnold had disapproved of such levity.那时候的阿诺德对这种轻浮行为很看不惯。
326 drawn MuXzIi     
v.拖,拉,拔出;adj.憔悴的,紧张的
参考例句:
  • All the characters in the story are drawn from life.故事中的所有人物都取材于生活。
  • Her gaze was drawn irresistibly to the scene outside.她的目光禁不住被外面的风景所吸引。
327 creed uoxzL     
n.信条;信念,纲领
参考例句:
  • They offended against every article of his creed.他们触犯了他的每一条戒律。
  • Our creed has always been that business is business.我们的信条一直是公私分明。
328 negation q50zu     
n.否定;否认
参考例句:
  • No reasonable negation can be offered.没有合理的反对意见可以提出。
  • The author boxed the compass of negation in his article.该作者在文章中依次探讨了各种反面的意见。
329 repelled 1f6f5c5c87abe7bd26a5c5deddd88c92     
v.击退( repel的过去式和过去分词 );使厌恶;排斥;推开
参考例句:
  • They repelled the enemy. 他们击退了敌军。 来自《简明英汉词典》
  • The minister tremulously, but decidedly, repelled the old man's arm. 而丁梅斯代尔牧师却哆里哆嗦地断然推开了那老人的胳臂。 来自英汉文学 - 红字
330 entity vo8xl     
n.实体,独立存在体,实际存在物
参考例句:
  • The country is no longer one political entity.这个国家不再是一个统一的政治实体了。
  • As a separate legal entity,the corporation must pay taxes.作为一个独立的法律实体,公司必须纳税。
331 salvation nC2zC     
n.(尤指基督)救世,超度,拯救,解困
参考例句:
  • Salvation lay in political reform.解救办法在于政治改革。
  • Christians hope and pray for salvation.基督教徒希望并祈祷灵魂得救。
332 interpretation P5jxQ     
n.解释,说明,描述;艺术处理
参考例句:
  • His statement admits of one interpretation only.他的话只有一种解释。
  • Analysis and interpretation is a very personal thing.分析与说明是个很主观的事情。
333 judicially 8e141e97c5a0ea74185aa3796a2330c0     
依法判决地,公平地
参考例句:
  • Geoffrey approached the line of horses and glanced judicially down the row. 杰弗里走进那栏马,用审视的目的目光一匹接一匹地望去。
  • Not all judicially created laws are based on statutory or constitutional interpretation. 并不是所有的司法机关创制的法都以是以成文法或宪法的解释为基础的。
334 transmute KmWwy     
vt.使变化,使改变
参考例句:
  • We can transmute water power into electrical power.我们能将水力变成电力。
  • A radioactive atom could transmute itself into an entirely different kind of atom.放射性原子本身能嬗变为性质完全不同的另一种原子。
335 permanently KluzuU     
adv.永恒地,永久地,固定不变地
参考例句:
  • The accident left him permanently scarred.那次事故给他留下了永久的伤疤。
  • The ship is now permanently moored on the Thames in London.该船现在永久地停泊在伦敦泰晤士河边。
336 faculty HhkzK     
n.才能;学院,系;(学院或系的)全体教学人员
参考例句:
  • He has a great faculty for learning foreign languages.他有学习外语的天赋。
  • He has the faculty of saying the right thing at the right time.他有在恰当的时候说恰当的话的才智。
337 saturated qjEzG3     
a.饱和的,充满的
参考例句:
  • The continuous rain had saturated the soil. 连绵不断的雨把土地淋了个透。
  • a saturated solution of sodium chloride 氯化钠饱和溶液
338 foretell 9i3xj     
v.预言,预告,预示
参考例句:
  • Willow trees breaking out into buds foretell the coming of spring.柳枝绽青报春来。
  • The outcome of the war is hard to foretell.战争胜负难以预卜。
339 deferred 43fff3df3fc0b3417c86dc3040fb2d86     
adj.延期的,缓召的v.拖延,延缓,推迟( defer的过去式和过去分词 );服从某人的意愿,遵从
参考例句:
  • The department deferred the decision for six months. 这个部门推迟了六个月才作决定。
  • a tax-deferred savings plan 延税储蓄计划
340 defer KnYzZ     
vt.推迟,拖延;vi.(to)遵从,听从,服从
参考例句:
  • We wish to defer our decision until next week.我们希望推迟到下星期再作出决定。
  • We will defer to whatever the committee decides.我们遵从委员会作出的任何决定。
341 decomposing f5b8fd5c51324ed24e58a14c223dc3da     
腐烂( decompose的现在分词 ); (使)分解; 分解(某物质、光线等)
参考例句:
  • The air was filled with the overpowering stench of decomposing vegetation. 空气中充满了令人难以忍受的腐烂植物的恶臭。
  • Heat was obtained from decomposing manures and hot air flues. 靠肥料分解和烟道为植物提供热量。
342 acidity rJyya     
n.酸度,酸性
参考例句:
  • This plant prefers alkaline soil,though it will readily tolerate some acidity.这种植物在酸性土壤中也能生存,但硷性土壤更加适宜。
  • Gastric acidity would not prevent the organism from passing into the gut.胃的酸度不能防止细菌进入肠道。
343 exclusion 1hCzz     
n.拒绝,排除,排斥,远足,远途旅行
参考例句:
  • Don't revise a few topics to the exclusion of all others.不要修改少数论题以致排除所有其他的。
  • He plays golf to the exclusion of all other sports.他专打高尔夫球,其他运动一概不参加。
344 revival UWixU     
n.复兴,复苏,(精力、活力等的)重振
参考例句:
  • The period saw a great revival in the wine trade.这一时期葡萄酒业出现了很大的复苏。
  • He claimed the housing market was showing signs of a revival.他指出房地产市场正出现复苏的迹象。
345 dexterous Ulpzs     
adj.灵敏的;灵巧的
参考例句:
  • As people grow older they generally become less dexterous.随着年龄的增长,人通常会变得不再那么手巧。
  • The manager was dexterous in handling his staff.那位经理善于运用他属下的职员。
346 combustible yqizS     
a. 易燃的,可燃的; n. 易燃物,可燃物
参考例句:
  • Don't smoke near combustible materials. 别在易燃的材料附近吸烟。
  • We mustn't take combustible goods aboard. 我们不可带易燃品上车。
347 humbling 643ebf3f558f4dfa49252dce8143a9c8     
adj.令人羞辱的v.使谦恭( humble的现在分词 );轻松打败(尤指强大的对手);低声下气
参考例句:
  • A certain humbling from time to time is good. 不时受点儿屈辱是有好处的。 来自辞典例句
  • It has been said that astronomy is a humbling and character-buildingexperience. 据说天文学是一种令人产生自卑、塑造人格的科学。 来自互联网
348 requited 7e241adc245cecc72f302a4bab687327     
v.报答( requite的过去式和过去分词 );酬谢;回报;报复
参考例句:
  • I requited him for his help with a present. 我送他一份礼以答谢他的帮助。 来自辞典例句
  • His kindness was requited with cold contempt. 他的好意被报以 [遭致] 冷淡的轻蔑。 来自辞典例句


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