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CHAPTER VII.
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  Newton’s Theory of the Colours of Natural Bodies explained—Objections to it stated—New Classification of Colours—Outline of a New Theory proposed.

If the objects of the material world had been illuminated1 with white light, all the particles of which possessed2 the same degree of refrangibility, and were equally acted upon by the bodies on which they fall, all nature would have shone with a leaden hue3, and all the combinations of external objects, and all the features of the human countenance4, would have exhibited no other variety but that which they possess in a pencil sketch5 or a China-ink drawing. The rainbow itself would have dwindled6 into a narrow arch of white light,—the stars would have shone through a gray sky,—and the mantle7 of a wintry twilight8 would have replaced the golden vesture of the rising and the setting sun. But He who has exhibited such matchless skill in the organization of material bodies, and such exquisite9 taste in the forms upon which they are modelled, has superadded that ethereal beauty which enhances their more permanent qualities, and presents them to us in the ever-varying colours of the spectrum10. Without this the foliage11 of vegetable life might have filled the eye and fostered the fruit which it veils,—but the youthful green of its spring would have been blended with the dying yellow of its autumn. Without this the diamond might have displayed to science the beauty of its forms, and yielded to the arts its adamantine virtues;—but it would have ceased to shine in the chaplet of beauty, and to sparkle in the diadem12 of princes. Without this the human countenance might83 have expressed all the sympathies of the heart, but the “purple light of love” would not have risen on the cheek, nor the hectic13 flush been the herald14 of its decay.

The gay colouring with which the Almighty15 has decked the pale marble of nature is not the result of any quality inherent in the coloured body, or in the particles by which it may be tinged16, but is merely a property of the light in which they happen to be placed. Newton was the first person who placed this great truth in the clearest evidence. He found that all bodies, whatever were their peculiar18 colours, exhibited these colours only in white light. When they were illuminated by homogeneous red light they appeared red, by homogeneous yellow light, yellow, and so on, “their colours being most brisk and vivid under the influence of their own daylight colours.” The leaf of a plant, for example, appeared green in the white light of day, because it had the property of reflecting that light in greater abundance than any other. When it was placed in homogeneous red light, it could no longer appear green, because there was no green light to reflect; but it reflected a portion of red light, because there was some red in the compound green which it had the property of reflecting. Had the leaf originally reflected a pure homogeneous green, unmixed with red, and reflected no white light from its outer surface, it would have appeared quite black in pure homogeneous red light, as this light does not contain a single ray which the leaf was capable of reflecting. Hence the colours of material bodies are owing to the property which they possess of stopping certain rays of white light, while they reflect or transmit to the eye the rest of the rays of which white light is composed.

So far the Newtonian doctrine19 of colours is capable of rigid20 demonstration21; but its author was not content with carrying it thus far: he sought to84 determine the manner in which particular rays are stopped, while others are reflected or transmitted; and the result of this profound inquiry22 was his theory of the colours of natural bodies, which was communicated to the Royal Society on the 10th February, 1675. This theory is perhaps the loftiest of all his speculations23; and though, as a physical generalization24, it stands on a perishable25 basis, and must soon be swept away in the progress of science, it yet bears the deepest impress of the grasp of his powerful intellect.

The principles upon which this theory is founded are the following:—

1. Bodies that have the greatest refractive powers reflect the greatest quantity of light; and at the confines of equally refracting media there is no reflection.

2. The least particles of almost all natural bodies are in some measure transparent26.

3. Between the particles of bodies are many pores or spaces, either empty or filled with media of less density27 than the particles.

4. The particles of bodies and their pores, or the spaces between the particles, have some definite size.

Upon these principles Newton explains the origin of transparency, opacity28, and colour.

Transparency he considers as arising from the particles and their intervals29 or pores being too small to cause reflection at their common surfaces,19 so that all the light which enters transparent bodies passes through them without any portion of it being turned from its path by reflection. If we could obtain, for example, a film of mica30 whose thickness does not exceed two-thirds of the millionth part of an inch, all the light which fell upon it would pass through it, and none would be reflected. If this film was then85 cut into fragments, a number of such fragments would constitute a bundle, which would also transmit all the light which fell upon it, and be perfectly31 transparent.

Opacity in bodies arises, he thinks, from an opposite cause, viz. when the parts of bodies are of such a size as to be capable of reflecting the light which falls upon them, in which case the light is “stopped or stifled33” by the multitude of reflections.

The colours of natural bodies have, in the Newtonian hypothesis, the same origin as the colours of thin plates, their transparent particles, according to their several sizes, reflecting rays of one colour, and transmitting those of another. “For if a thinned or plated body which, being of an uneven34 thickness, appears all over of one uniform colour, should be slit35 into threads, or broken into fragments of the same thickness with the plate or film, every thread or fragment should keep its colour, and consequently, a heap of such threads or fragments should constitute a mass or powder of the same colour which the plate exhibited before it was broken: and the parts of all natural bodies being like so many fragments of a plate, must, on the same grounds, exhibit the same colour.”

Such is the theory of the colours of natural bodies, stated as clearly and briefly36 as we can. It has been very generally admitted by philosophers, both of our own and of other countries, and has been recently illustrated37 and defended by a French philosopher of distinguished38 eminence39. That this theory affords the true explanation of certain colours, or, to speak more correctly, that certain colours in natural bodies are the colours of thin plates, cannot be doubted; but it will not be difficult to show that it is quite inapplicable to that great class of phenomena40 which may be considered as representing the colours of natural bodies.

The first objection to the Newtonian theory is the86 total absence of all reflected light from the particles of transparent coloured media, such as coloured gems41, coloured glasses, and coloured fluids. This objection was urged long ago by Mr. Delaval, who placed coloured fluids on black grounds, and never could perceive the least trace of the reflected tints42. I have repeated the experiment with every precaution, and with every variation that I could think of, and I consider it as an established fact, that in such coloured bodies the complementary reflected colour cannot be rendered visible. If the fluid, for example, be red, the green light from which the red has been separated ought to appear either directly by looking into the coloured mass, or ought to be recognised by its influence in modifying the light really reflected; but as it cannot be seen, we must conclude that it has not been reflected, but has been destroyed by some other property of the coloured body.

A similar objection may be drawn44 from the disappearance45 of the transmitted complementary colour in the leaves of plants and petals46 of flowers. I have ascertained47 from numerous experiments, that the transmitted colour is almost invariably the same with the reflected colour, and that the same holds true with the coloured juices expressed from them. The complementary tints are never seen, and wherever there has been any thing like an approximation to two tints, I have invariably found that it arose from there being two different coloured juices existing in different sides of the leaf.

In the phenomena of the light transmitted by coloured glasses, there are some peculiarities48 which, we think, demonstrate that their colours are not those of thin plates. The light, for example, transmitted through a particular kind of blue glass, has a blue colour of such a peculiar composition that there is no blue in any of the orders of colours in thin plates which has any resemblance to it. It is entirely87 destitute50 of the red rays which form the middle of the red space in the spectrum; so that the particles on which the colour depends must reflect the middle red rays, and transmit those on each side of it,—a property which cannot be deduced from the Newtonian doctrine.

The explanation of opacity, as arising from a multitude of reflections, is liable to the same objection which we have urged against the explanation of colour. In order to appreciate its weight, we must distinguish opacity into two kinds, namely, the opacity of whiteness and the opacity of blackness. Those bodies which possess the power of reflection in the highest degree, such as white metals, chalk, and plaster of Paris, never reflect more than one-half of the light which falls upon them. The other half of the incident light is, according to Newton, lost by a multitude of reflections. But how is it lost? Reflection merely changes the direction of the particles of light, so that they must again emerge from the body, unless they are reflected into fixed51 returning orbits, which detain them for ever in a state of motion within the body. In the case of black opacity, such as that of coal, which reflects from its first surface only 1/25th of the white light, the difficulty is still greater, and we cannot conceive how any system of interior reflections could so completely stifle32 24/25ths of the whole incident light, without some of it returning to the eye in a visible form.

In determining the constitution of bodies that produce transparency and blackness, the Newtonian theory encounters a difficulty which its author has by no means surmounted52. Transparency, as we have already seen, arises from the “particles and their interstices being too small to cause reflections in their common surfaces,” that is, they must be “less than any of those which exhibit colours,” or “less than is requisite53 to reflect the white and very88 faint blue of the first order. But this is the very same constitution which produces blackness by reflection, and in order to explain the cause of blackness by transmission, or black opacity, Newton is obliged to introduce a new principle.

“For the production of black,” says he, “the corpuscles must be less than any of those which exhibit colours. For at all greater sizes there is too much light reflected to constitute this colour. But if they be supposed a little less than is requisite to reflect the white and very faint blue of the first order, they will reflect so very little light as to appear intensely black, and yet may perhaps variously refract20 it to and fro within themselves so long, until it happens to be stifled and lost, by which means they will appear black in all positions of the eye, without any transparency.”

This very remarkable54 passage exhibits, in a striking manner, the perplexity in which our author was involved by the difficulties of his subject. As the particles which produce blackness by reflection are necessarily so small as to exclude the existence of any reflective forces, he cannot ascribe the loss of the intromitted light, as he does in the case of white opacity, to “a multitude of reflections;” and therefore he is compelled to have recourse to refracting forces to perform the same office. The reluctance55 with which he avails himself of this expedient56 is well marked in the mode of expression which he adopts; and I am persuaded that when he wrote the above passage, he felt the full force of the objections to this hypothesis, which cannot fail to present themselves. As the size of the particles which produce blackness are intermediate between those89 which produce transparency and those which produce colour, approaching closely to the latter, it is difficult to conceive why they should refract the intromitted light, while the greater and smaller particles, and even those almost of the same size, should be destitute of that property. It is, besides, not easy to understand how a refraction can take place within bodies which shall stifle all the light, and prevent it from emerging. Nay57, we may admit the existence of such refractions, and yet understand how, by a compensation in their direction, the refracted rays may all emerge from the opaque58 body.

The force of these objections is tacitly recognised in Pemberton’s View of Sir Isaac Newton’s Philosophy;21 and as Newton not only read and approved of that work, but even perused59 a great part of it along with its author, we may fairly consider the opinion there stated to be his own.

“For producing black, the particles ought to be smaller than for exhibiting any of the colours, viz. of a size answering to the thickness of the bubble, whereby reflecting little or no light, it appears colourless; but yet they must not be too small, for that will make them transparent through deficiency of reflections in the inward parts of the body, sufficient to stop the light from going through it; but they must be of a size bordering upon that disposed to reflect the faint blue of the first order, which affords an evident reason why blacks usually partake a little of that colour.” In this passage all idea of refraction is abandoned, and that precise degree of size is assumed for the particles which leaves a small power of reflection, which is deemed sufficient to prevent the body from becoming transparent; that is, sufficient to render it opaque or black.

The last objection which we shall state to this theory is one to which we attach great weight, and,90 as it is founded on discoveries and views which have been published since the time of Newton, we venture to believe, that, had he been aware of them, he would never have proposed the theory which we are considering.

When light falls upon a thin film such as AEC, fig60. 9, p. 80, so as to produce the colours of thin plates, it follows, from Sir Isaac Newton’s theory of fits, that a portion of the light is, as usual, reflected at the first surface AE,22 while the light which forms the coloured image is that which is reflected from the second surface EC, so that all the colours of thin plates are diluted62 with the white light reflected from the first surface. Now, in the modern theory, which ascribes the colours of thin plates to the interference of the light reflected from the second surface EC, with the light reflected from the first surface AE, the resulting tint43 arises from the combination of these two pencils, and consequently there is no white light reflected from the surface AE. In like manner, when the thickness of the film is such that the two interfering63 pencils completely destroy one another, and produce black, there is not a ray of light reflected from the first surface. Here, then, we have a criterion for deciding between the theory of fits and the theory of interference; for if there is no white light reflected from the first surface AE, the theory of fits must be rejected. In a remarkable phenomenon of blackness arising from minute fibres, which I have had occasion to describe, there was no perceptible reflection from the surface of the fibres;23 and M. Fresnel describes an experiment made to determine the same point, and states the result of it to91 have been unequivocally in favour of the doctrine of interference.

In order to apply this important fact, let us take a piece of coal, one of the blackest and most opaque of all substances, and which does not reflect to the eye a single ray out of those which enter its substance. The size of its particles is so small, that they are incapable64 of reflecting light. When a number of these particles are placed together, so as to form a surface, and other particles behind them, so as to form a solid, they will not acquire by this process the power of reflection; and consequently, a piece of coal so composed should be destitute of the property of reflecting light from its first surface. But this is not the case,—light is abundantly reflected from the first surface of the coal, and consequently, its elementary particles must possess the same power. Hence the blackness of coal must be ascribed to some other cause than to the minuteness of its transparent atoms.

To transparent bodies this argument has a similar application. As their atoms are still less than those of black bodies, their inability to reflect light is still greater, and hence arises their transparency. But the particles forming the surface of such bodies do reflect light, and, therefore, their transparency must have another origin.

In the case of coloured bodies, too, the particles forming their surfaces reflect white light like those of all other bodies, so that these particles cannot produce colour on the same principles as those of thin plates. In many of those cases of colour which seem to depend upon the minuteness of the particles of the body, the reflection of white light may nevertheless be observed, but this will be found to arise from a thin transparent film, behind which the colorific particles are placed.

Whatever answer may be given to these objections, we think it will be admitted by those who92 have studied the subject most profoundly, that a satisfactory theory of the colours of natural bodies is still a desideratum in science. How far we may be able to approach to it in the present state of optics the reader will judge from the following views.

Colours may be arranged into seven classes, each of which depends upon different principles.

1. Transparent coloured fluids—transparent coloured gems—transparent coloured glasses—coloured powders—and the colours of the leaves and flowers of plants.

2. Oxidations on metals—colours of Labrador feldspar—colours of precious and hydrophanous opal, and other opalescences—the colours of the feathers of birds, of the wings of insects, and of the scales of fishes.

3. Superficial colours, as those of mother-of-pearl and striated65 surfaces.

4. Opalescences and colours in composite crystals having double refraction.

5. Colours from the absorption of common and polarized light by doubly refracting crystals.

6. Colours at the surfaces of media of different dispersive66 powers.

7. Colours at the surface of media in which the reflecting forces extend to different distances, or follow different laws.

The first two of these classes are the most important. The Newtonian theory appears to be strictly67 applicable to the phenomena of the second class; but those of the first class cannot, we conceive, be referred to the same cause.
* * * * *

The rays of solar light possess several remarkable physical properties: They heat—they illuminate—they promote chymical combination—they effect chymical decompositions—they impart magnetism68 to steel—they alter the colours of bodies—they93 communicate to plants and flowers their peculiar colours, and are in many cases necessary to the development of their characteristic qualities. It is impossible to admit for a moment that these varied69 effects are produced by a mere17 mechanical action, or that they arise from the agitation70 of the particles of bodies by the vibration71 of the ether which is considered to be the cause of light. Whatever be the difficulties which attach to the theory which supposes light to consist of material particles, we are compelled, by its properties, to admit that light acts as if it were material, and that it enters into combinations with bodies, in order to produce the effects which we have enumerated72.

When a beam of light falls upon a body, and the whole or a part of that which enters its substance totally disappears, we are entitled to say, that it is detained by some power exercised by the particles of the body over the particles of light. When this light is said to be lost by a multitude of reflections or refractions, the statement is not only hypothetical, but it is an hypothesis incompatible73 with optical principles. That the light detained within bodies has been stopped by the attractive force of the particles seems to be highly probable, and the mind will not feel any repugnance74 to admit that the particles of all bodies, whether solid, fluid, or a?riform, have a specific affinity75 for the particles of light. Considering light, therefore, as material, it is not difficult to comprehend how it should, like other elementary substances, enter into combination with bodies, and produce many chymical and physical effects, but particularly the phenomena of transparency, opacity, and colour.

In transparent colourless bodies, such as water and glass, the intromitted light experiences a considerable loss, because a certain number of its particles are attracted and detained by the atoms of the water or glass, and the light which emerges is94 colourless, because the particles exercise a proportional action over all the simple colours which compose white light.

When the transparent body has any decided76 colour, such as those enumerated in Class I., then the particles of the body have exercised a specific attraction over those rays of white light which are complementary to those which compose the colour of the transmitted light. If the transparent body, for example, is red, then its particles have detained the green rays which entered into the incident light, or certain other rays, which with the red are necessary to compose white light. In compound bodies, like some of the artificial glasses, the particles will attract and detain rays of light of different colours, as may be seen by analyzing77 the transmitted light with a prism, which will exhibit a spectrum deprived of all the rays which have been detained. In black bodies the particles exercise a powerful attraction over light, and detain all the intromitted rays.

When coloured bodies are opaque, so as to exhibit their colours principally by reflection, the light which is reflected back to the observer has received its colour from transmission through part of the thickness of the body, or, what is the same thing, the colour reflected to the eye is complementary to that which has been detained by the particles of the body while the light is passing and repassing through a thickness terminated by the reflecting surfaces; and as only a part of this light is reflected, as in the case of leaves and flowers, the transmitted light must have the same colour as the reflected light.

When coloured bodies exhibit two different colours complementary to each other, the one seen by reflection and the other by transmission, it is then highly probable that the colours are those of thin plates, though there are still other optical principles to which they may be referred. As the particles of95 bodies, and the medium which unites them, or, as the different atoms of a compound body may have different dispersive powers, while they exercise the same refractive force over a particular part of the spectrum, the rays for which this compensation takes place will be transmitted, while part of the complementary light is reflected.24 Or in cases where the refractive and dispersive powers are the same, the reflective forces of the particles may vary according to a different law, so that at the separating surfaces either white or coloured light may be reflected.25

In those cases of colour where the reflected and the transmitted tints are not complementary, as in leaf-gold, where the former is yellow and the latter green;—in leaf-silver, where they are white and blue, and in certain pieces of fir-wood, where the reflected light is whitish yellow, and the transmitted light a brilliant homogeneous red, we may explain the separation of the colours either by the principles we have already laid down or by the doctrine of thin plates. On the first principle, the colour of the reflected light, which is supposed to be the same as that of the transmitted light, will be modified by the law according to which the particles of the body attract different rays out of the beam of white light. In pitch, for example, the blue rays are first absorbed, so that at small thicknesses the transmitted light is a fine yellow, while, by the action of a greater thickness, the yellow itself is absorbed, and the transmitted light is a bright homogeneous red. Now in leaf-gold the transmitted colour of thinner films than we can obtain may be yellow, and, consequently, the light reflected from the first strata78 of interrupting faces will be yellow, and will determine the predominant tint of the reflected light. On the Newtonian doctrine, Mr. Herschel has explained it96 by saying, “that the transmitted rays have traversed the whole thickness of the medium, and therefore undergo many more times the action of its atoms than those reflected, especially those near the first surface to which the brighter part of the reflected colour is due.”

The phenomena of the absorption of common and polarized light, which I have described in another place,26 throw much light on the subject of coloured bodies. The relation of the absorbent action to the axes of double refraction, and, consequently, to the poles of the molecules79 of the crystal, shows how the particles of light attracted by the molecules of the body will vary, both in their nature and number, according to the direction in which they approach the molecules; and explains how the colour of a body may be changed, either temporarily or permanently80, by heat, according as it produces a temporary or a permanent change in the relative position of the molecules. This is not the place to enlarge on this subject; but we may be permitted to apply the idea to the curious experiment of Thenard on phosphorus. When this substance is rendered pure by repeated distillation81, it is transparent, and transmits yellow light; but when it is thrown in a melted state into cold water, it becomes jet black. When again melted, it resumes its original colour and transparency. According to the Newtonian theory, we must suppose that the atoms of the phosphorus have been diminished in size by sudden cooling,—an effect which it is not easy to comprehend; but, according to the preceding views, we may suppose that the atoms of the phosphorus have been forced by sudden cooling into relative positions quite different from those which they take when they slowly assume the solid state, and their poles of maximum attraction, in97 place of being turned to one another, are turned in different directions, and then allowed to exercise their full action in attracting the intromitted light, and detaining it wholly within the body.27

Before concluding this chapter, there is one topic peculiarly deserving our notice, namely, the change of colour produced in bodies by continued exposure to light. The general effect of light is to diminish or dilute61 the colours of bodies, and in many cases to deprive them entirely49 of their colour. Now, it is not easy to understand how repeated undulations propagated through a body could diminish the size of its particles, or how the same effect could be produced by a multitude of reflections from particle to particle. But if light is attracted by the particles of bodies, and combines with them, it is easy to conceive that, when the molecules of a body have combined with a great number of particles of a green colour, for example, their power of combination with others will be diminished, and, consequently, the number of particles of any colour absorbed or detained must diminish with the time that the body has been exposed to light; that is, these particles must enter into the transmitted and reflected pencils, and diminish the intensity82 of their colour. If the body, for example, absorbs red light, and transmits and reflects green, then if the quantity of absorbed red light is diminished, it will enter into the reflected and transmitted pencils, and, forming white light by its mixture with a portion of the green rays, will actually dilute them in the same manner as if a portion of white light had been added.

点击收听单词发音收听单词发音  

1 illuminated 98b351e9bc282af85e83e767e5ec76b8     
adj.被照明的;受启迪的
参考例句:
  • Floodlights illuminated the stadium. 泛光灯照亮了体育场。
  • the illuminated city at night 夜幕中万家灯火的城市
2 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。
3 hue qdszS     
n.色度;色调;样子
参考例句:
  • The diamond shone with every hue under the sun.金刚石在阳光下放出五颜六色的光芒。
  • The same hue will look different in different light.同一颜色在不同的光线下看起来会有所不同。
4 countenance iztxc     
n.脸色,面容;面部表情;vt.支持,赞同
参考例句:
  • At the sight of this photograph he changed his countenance.他一看见这张照片脸色就变了。
  • I made a fierce countenance as if I would eat him alive.我脸色恶狠狠地,仿佛要把他活生生地吞下去。
5 sketch UEyyG     
n.草图;梗概;素描;v.素描;概述
参考例句:
  • My sister often goes into the country to sketch. 我姐姐常到乡间去写生。
  • I will send you a slight sketch of the house.我将给你寄去房屋的草图。
6 dwindled b4a0c814a8e67ec80c5f9a6cf7853aab     
v.逐渐变少或变小( dwindle的过去式和过去分词 )
参考例句:
  • Support for the party has dwindled away to nothing. 支持这个党派的人渐渐化为乌有。
  • His wealth dwindled to nothingness. 他的钱财化为乌有。 来自《简明英汉词典》
7 mantle Y7tzs     
n.斗篷,覆罩之物,罩子;v.罩住,覆盖,脸红
参考例句:
  • The earth had donned her mantle of brightest green.大地披上了苍翠欲滴的绿色斗篷。
  • The mountain was covered with a mantle of snow.山上覆盖着一层雪。
8 twilight gKizf     
n.暮光,黄昏;暮年,晚期,衰落时期
参考例句:
  • Twilight merged into darkness.夕阳的光辉融于黑暗中。
  • Twilight was sweet with the smell of lilac and freshly turned earth.薄暮充满紫丁香和新翻耕的泥土的香味。
9 exquisite zhez1     
adj.精美的;敏锐的;剧烈的,感觉强烈的
参考例句:
  • I was admiring the exquisite workmanship in the mosaic.我当时正在欣赏镶嵌画的精致做工。
  • I still remember the exquisite pleasure I experienced in Bali.我依然记得在巴厘岛所经历的那种剧烈的快感。
10 spectrum Trhy6     
n.谱,光谱,频谱;范围,幅度,系列
参考例句:
  • This is a kind of atomic spectrum.这是一种原子光谱。
  • We have known much of the constitution of the solar spectrum.关于太阳光谱的构成,我们已了解不少。
11 foliage QgnzK     
n.叶子,树叶,簇叶
参考例句:
  • The path was completely covered by the dense foliage.小路被树叶厚厚地盖了一层。
  • Dark foliage clothes the hills.浓密的树叶覆盖着群山。
12 diadem uvzxB     
n.王冠,冕
参考例句:
  • The diadem is the symbol of royalty.王冠就是王权的象征。
  • Nature like us is sometimes caught without diadem.自然犹如我等,时常没戴皇冠。
13 hectic jdZzk     
adj.肺病的;消耗热的;发热的;闹哄哄的
参考例句:
  • I spent a very hectic Sunday.我度过了一个忙乱的星期天。
  • The two days we spent there were enjoyable but hectic.我们在那里度过的两天愉快但闹哄哄的。
14 herald qdCzd     
vt.预示...的来临,预告,宣布,欢迎
参考例句:
  • In England, the cuckoo is the herald of spring.在英国杜鹃鸟是报春的使者。
  • Dawn is the herald of day.曙光是白昼的先驱。
15 almighty dzhz1h     
adj.全能的,万能的;很大的,很强的
参考例句:
  • Those rebels did not really challenge Gods almighty power.这些叛徒没有对上帝的全能力量表示怀疑。
  • It's almighty cold outside.外面冷得要命。
16 tinged f86e33b7d6b6ca3dd39eda835027fc59     
v.(使)发丁丁声( ting的过去式和过去分词 )
参考例句:
  • memories tinged with sadness 略带悲伤的往事
  • white petals tinged with blue 略带蓝色的白花瓣
17 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。
18 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。
19 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。
20 rigid jDPyf     
adj.严格的,死板的;刚硬的,僵硬的
参考例句:
  • She became as rigid as adamant.她变得如顽石般的固执。
  • The examination was so rigid that nearly all aspirants were ruled out.考试很严,几乎所有的考生都被淘汰了。
21 demonstration 9waxo     
n.表明,示范,论证,示威
参考例句:
  • His new book is a demonstration of his patriotism.他写的新书是他的爱国精神的证明。
  • He gave a demonstration of the new technique then and there.他当场表演了这种新的操作方法。
22 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。
23 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》
24 generalization 6g4xv     
n.普遍性,一般性,概括
参考例句:
  • This sweeping generalization is the law of conservation of energy.这一透彻的概括就是能量守恒定律。
  • The evaluation of conduct involves some amount of generalization.对操行的评价会含有一些泛泛之论。
25 perishable 9uKyk     
adj.(尤指食物)易腐的,易坏的
参考例句:
  • Many fresh foods are highly perishable.许多新鲜食物都极易腐败。
  • Fruits are perishable in transit.水果在运送时容易腐烂。
26 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。
27 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。
28 opacity TvDy3     
n.不透明;难懂
参考例句:
  • He insisted that the mineral content of the water determined the opacity.他坚持认为水的清澈程度取决于其中矿物质的含量。
  • Opacity of the eye lens can be induced by deficiency of certain vitamins.眼球晶状体的混浊可由缺乏某些维生素造成。
29 intervals f46c9d8b430e8c86dea610ec56b7cbef     
n.[军事]间隔( interval的名词复数 );间隔时间;[数学]区间;(戏剧、电影或音乐会的)幕间休息
参考例句:
  • The forecast said there would be sunny intervals and showers. 预报间晴,有阵雨。
  • Meetings take place at fortnightly intervals. 每两周开一次会。
30 mica gjZyj     
n.云母
参考例句:
  • It could not pass through material impervious to water such as mica.它不能通过云母这样的不透水的物质。
  • Because of its layered structure,mica is fissile.因为是层状结构,云母很容易分成片。
31 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。
32 stifle cF4y5     
vt.使窒息;闷死;扼杀;抑止,阻止
参考例句:
  • She tried hard to stifle her laughter.她强忍住笑。
  • It was an uninteresting conversation and I had to stifle a yawn.那是一次枯燥无味的交谈,我不得不强忍住自己的呵欠。
33 stifled 20d6c5b702a525920b7425fe94ea26a5     
(使)窒息, (使)窒闷( stifle的过去式和过去分词 ); 镇压,遏制; 堵
参考例句:
  • The gas stifled them. 煤气使他们窒息。
  • The rebellion was stifled. 叛乱被镇压了。
34 uneven akwwb     
adj.不平坦的,不规则的,不均匀的
参考例句:
  • The sidewalk is very uneven—be careful where you walk.这人行道凹凸不平—走路时请小心。
  • The country was noted for its uneven distribution of land resources.这个国家以土地资源分布不均匀出名。
35 slit tE0yW     
n.狭长的切口;裂缝;vt.切开,撕裂
参考例句:
  • The coat has been slit in two places.这件外衣有两处裂开了。
  • He began to slit open each envelope.他开始裁开每个信封。
36 briefly 9Styo     
adv.简单地,简短地
参考例句:
  • I want to touch briefly on another aspect of the problem.我想简单地谈一下这个问题的另一方面。
  • He was kidnapped and briefly detained by a terrorist group.他被一个恐怖组织绑架并短暂拘禁。
37 illustrated 2a891807ad5907f0499171bb879a36aa     
adj. 有插图的,列举的 动词illustrate的过去式和过去分词
参考例句:
  • His lecture was illustrated with slides taken during the expedition. 他在讲演中使用了探险时拍摄到的幻灯片。
  • The manufacturing Methods: Will be illustrated in the next chapter. 制作方法将在下一章说明。
38 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。
39 eminence VpLxo     
n.卓越,显赫;高地,高处;名家
参考例句:
  • He is a statesman of great eminence.他是个声名显赫的政治家。
  • Many of the pilots were to achieve eminence in the aeronautical world.这些飞行员中很多人将会在航空界声名显赫。
40 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。
41 gems 74ab5c34f71372016f1770a5a0bf4419     
growth; economy; management; and customer satisfaction 增长
参考例句:
  • a crown studded with gems 镶有宝石的皇冠
  • The apt citations and poetic gems have adorned his speeches. 贴切的引语和珠玑般的诗句为他的演说词增添文采。
42 tints 41fd51b51cf127789864a36f50ef24bf     
色彩( tint的名词复数 ); 带白的颜色; (淡色)染发剂; 痕迹
参考例句:
  • leaves with red and gold autumn tints 金秋时节略呈红黄色的树叶
  • The whole countryside glowed with autumn tints. 乡间处处呈现出灿烂的秋色。
43 tint ZJSzu     
n.淡色,浅色;染发剂;vt.着以淡淡的颜色
参考例句:
  • You can't get up that naturalness and artless rosy tint in after days.你今后不再会有这种自然和朴实无华的红润脸色。
  • She gave me instructions on how to apply the tint.她告诉我如何使用染发剂。
44 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。
45 disappearance ouEx5     
n.消失,消散,失踪
参考例句:
  • He was hard put to it to explain her disappearance.他难以说明她为什么不见了。
  • Her disappearance gave rise to the wildest rumours.她失踪一事引起了各种流言蜚语。
46 petals f346ae24f5b5778ae3e2317a33cd8d9b     
n.花瓣( petal的名词复数 )
参考例句:
  • white petals tinged with blue 略带蓝色的白花瓣
  • The petals of many flowers expand in the sunshine. 许多花瓣在阳光下开放。 来自《现代英汉综合大词典》
47 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》
48 peculiarities 84444218acb57e9321fbad3dc6b368be     
n. 特质, 特性, 怪癖, 古怪
参考例句:
  • the cultural peculiarities of the English 英国人的文化特点
  • He used to mimic speech peculiarities of another. 他过去总是模仿别人讲话的特点。
49 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。
50 destitute 4vOxu     
adj.缺乏的;穷困的
参考例句:
  • They were destitute of necessaries of life.他们缺少生活必需品。
  • They are destitute of common sense.他们缺乏常识。
51 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。
52 surmounted 74f42bdb73dca8afb25058870043665a     
战胜( surmount的过去式和过去分词 ); 克服(困难); 居于…之上; 在…顶上
参考例句:
  • She was well aware of the difficulties that had to be surmounted. 她很清楚必须克服哪些困难。
  • I think most of these obstacles can be surmounted. 我认为这些障碍大多数都是可以克服的。
53 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。
54 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。
55 reluctance 8VRx8     
n.厌恶,讨厌,勉强,不情愿
参考例句:
  • The police released Andrew with reluctance.警方勉强把安德鲁放走了。
  • He showed the greatest reluctance to make a reply.他表示很不愿意答复。
56 expedient 1hYzh     
adj.有用的,有利的;n.紧急的办法,权宜之计
参考例句:
  • The government found it expedient to relax censorship a little.政府发现略微放宽审查是可取的。
  • Every kind of expedient was devised by our friends.我们的朋友想出了各种各样的应急办法。
57 nay unjzAQ     
adv.不;n.反对票,投反对票者
参考例句:
  • He was grateful for and proud of his son's remarkable,nay,unique performance.他为儿子出色的,不,应该是独一无二的表演心怀感激和骄傲。
  • Long essays,nay,whole books have been written on this.许多长篇大论的文章,不,应该说是整部整部的书都是关于这件事的。
58 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。
59 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
60 fig L74yI     
n.无花果(树)
参考例句:
  • The doctor finished the fig he had been eating and selected another.这位医生吃完了嘴里的无花果,又挑了一个。
  • You can't find a person who doesn't know fig in the United States.你找不到任何一个在美国的人不知道无花果的。
61 dilute FmBya     
vt.稀释,冲淡;adj.稀释的,冲淡的
参考例句:
  • The water will dilute the wine.水能使酒变淡。
  • Zinc displaces the hydrogen of dilute acids.锌置换了稀酸中的氢。
62 diluted 016e8d268a5a89762de116a404413fef     
无力的,冲淡的
参考例句:
  • The paint can be diluted with water to make a lighter shade. 这颜料可用水稀释以使色度淡一些。
  • This pesticide is diluted with water and applied directly to the fields. 这种杀虫剂用水稀释后直接施用在田里。
63 interfering interfering     
adj. 妨碍的 动词interfere的现在分词
参考例句:
  • He's an interfering old busybody! 他老爱管闲事!
  • I wish my mother would stop interfering and let me make my own decisions. 我希望我母亲不再干预,让我自己拿主意。
64 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。
65 striated striated     
adj.有纵线,条纹的
参考例句:
  • The striated and polished surfaces are called slicken-sides.有条痕的磨光面则称为擦痕面。
  • There are striated engravings on this wall.这面墙上有着条纹状的雕饰。
66 Dispersive Dispersive     
adj. 分散的
参考例句:
  • In many atomic fluorescence applications a non-dispersive optical system may be used. 在许多原子荧光法的应用中,可以采用非分散的光学系统。
  • The wave are of course dispersive. 当然这种波是弥散的。
67 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。
68 magnetism zkxyW     
n.磁性,吸引力,磁学
参考例句:
  • We know about magnetism by the way magnets act.我们通过磁铁的作用知道磁性是怎么一回事。
  • His success showed his magnetism of courage and devotion.他的成功表现了他的胆量和热诚的魅力。
69 varied giIw9     
adj.多样的,多变化的
参考例句:
  • The forms of art are many and varied.艺术的形式是多种多样的。
  • The hotel has a varied programme of nightly entertainment.宾馆有各种晚间娱乐活动。
70 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。
71 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。
72 enumerated 837292cced46f73066764a6de97d6d20     
v.列举,枚举,数( enumerate的过去式和过去分词 )
参考例句:
  • A spokesperson enumerated the strikers' demands. 发言人列数罢工者的要求。 来自《简明英汉词典》
  • He enumerated the capitals of the 50 states. 他列举了50个州的首府。 来自《现代汉英综合大词典》
73 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。
74 repugnance oBWz5     
n.嫌恶
参考例句:
  • He fought down a feelings of repugnance.他抑制住了厌恶感。
  • She had a repugnance to the person with whom she spoke.她看不惯这个和她谈话的人。
75 affinity affinity     
n.亲和力,密切关系
参考例句:
  • I felt a great affinity with the people of the Highlands.我被苏格兰高地人民深深地吸引。
  • It's important that you share an affinity with your husband.和丈夫有共同的爱好是十分重要的。
76 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。
77 analyzing be408cc8d92ec310bb6260bc127c162b     
v.分析;分析( analyze的现在分词 );分解;解释;对…进行心理分析n.分析
参考例句:
  • Analyzing the date of some socialist countries presents even greater problem s. 分析某些社会主义国家的统计数据,暴露出的问题甚至更大。 来自辞典例句
  • He undoubtedly was not far off the mark in analyzing its predictions. 当然,他对其预测所作的分析倒也八九不离十。 来自辞典例句
78 strata GUVzv     
n.地层(复数);社会阶层
参考例句:
  • The older strata gradually disintegrate.较老的岩层渐渐风化。
  • They represent all social strata.他们代表各个社会阶层。
79 molecules 187c25e49d45ad10b2f266c1fa7a8d49     
分子( molecule的名词复数 )
参考例句:
  • The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
  • Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里,大分子裂变为小分子。
80 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。
81 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。
82 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。


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