Besides the motions already spoken of, we have still to consider those that appertain to the auricles.
Caspar Bauhin and John Riolan,5 most learned men and skilful1 anatomists, inform us that from their observations, that if we carefully watch the movements of the heart in the vivisection of an animal, we shall perceive four motions distinct in time and in place, two of which are proper to the auricles, two to the ventricles. With all deference2 to such authority I say that there are four motions distinct in point of place, but not of time; for the two auricles move together, and so also do the two ventricles, in such wise that though the places be four, the times are only two. And this occurs in the following manner:
There are, as it were, two motions going on together: one of the auricles, another of the ventricles; these by no means taking place simultaneously3, but the motion of the auricles preceding, that of the heart following; the motion appearing to begin from the auricles and to extend to the ventricles. When all things are becoming languid, and the heart is dying, as also in fishes and the colder blooded animals there is a short pause between these two motions, so that the heart aroused, as it were, appears to respond to the motion, now more quickly, now more tardily4; and at length, when near to death, it ceases to respond by its proper motion, but seems, as it were, to nod the head, and is so slightly moved that it appears rather to give signs of motion to the pulsating5 auricles than actually to move. The heart, therefore, ceases to pulsate6 sooner than the auricles, so that the auricles have been said to outlive it, the left ventricle ceasing to pulsate first of all; then its auricle, next the right ventricle; and, finally, all the other parts being at rest and dead, as Galen long since observed, the right auricle still continues to beat; life, therefore, appears to linger longest in the right auricle. Whilst the heart is gradually dying, it is sometimes seen to reply, after two or three contractions8 of the auricles, roused as it were to action, and making a single pulsation9, slowly, unwillingly10, and with an effort.
But this especially is to be noted11, that after the heart has ceased to beat, the auricles however still contracting, a finger placed upon the ventricles perceives the several pulsations of the auricles, precisely12 in the same way and for the same reason, as we have said, that the pulses of the ventricles are felt in the arteries13, to wit, the distension14 produced by the jet of blood. And if at this time, the auricles alone pulsating, the point of the heart be cut off with a pair of scissors, you will perceive the blood flowing out upon each contraction7 of the auricles. Whence it is manifest that the blood enters the ventricles, not by any attraction or dilatation of the heart, but by being thrown into them by the pulses of the auricles.
And here I would observe, that whenever I speak of pulsations as occurring in the auricles or ventricles, I mean contractions: first the auricles contract, and then and subsequently the heart itself contracts. When the auricles contract they are seen to become whiter, especially where they contain but little blood; but they are filled as magazines or reservoirs of the blood, which is tending spontaneously and, by its motion in the veins15, under pressure towards the centre; the whiteness indicated is most conspicuous16 towards the extremities17 or edges of the auricles at the time of their contractions.
In fishes and frogs, and other animals which have hearts with but a single ventricle, and for an auricle have a kind of bladder much distended18 with blood, at the base of the organ, you may very plainly perceive this bladder contracting first, and the contraction of the heart or ventricle following afterwards.
But I think it right to describe what I have observed of an opposite character: the heart of an eel19, of several fishes, and even of some (of the higher) animals taken out of the body, pulsates20 without auricles; nay21, if it be cut in pieces the several parts may still be seen contracting and relaxing; so that in these creatures the body of the heart may be seen pulsating and palpitating, after the cessation of all motion in the auricle. But is not this perchance peculiar22 to animals more tenacious23 of life, whose radical24 moisture is more glutinous25, or fat and sluggish26, and less readily soluble27? The same faculty28 indeed appears in the flesh of eels29, which even when skinned and embowelled, and cut into pieces, are still seen to move.
Experimenting with a pigeon upon one occasion, after the heart had wholly ceased to pulsate, and the auricles too had become motionless, I kept my finger wetted with saliva30 and warm for a short time upon the heart, and observed that under the influence of this fomentation it recovered new strength and life, so that both ventricles and auricles pulsated31, contracting and relaxing alternately, recalled as it were from death to life.
Besides this, however, I have occasionally observed, after the heart and even its right auricle had ceased pulsating — when it was in articulo mortis in short — that an obscure motion, an undulation or palpitation, remained in the blood itself, which was contained in the right auricle, this being apparent so long as it was imbued32 with heat and spirit. And, indeed, a circumstance of the same kind is extremely manifest in the course of the generation of animals, as may be seen in the course of the first seven days of the incubation of the chick: A drop of blood makes its appearance which palpitates, as Aristotle had already observed; from this, when the growth is further advanced and the chick is fashioned, the auricles of the heart are formed, which pulsating henceforth give constant signs of life. When at length, and after the lapse33 of a few days, the outline of the body begins to be distinguished34, then is the ventricular part of the heart also produced, but it continues for a time white and apparently35 bloodless, like the rest of the animal; neither does it pulsate or give signs of motion. I have seen a similar condition of the heart in the human foetus about the beginning of the third month, the heart then being whitish and bloodless, although its auricles contained a considerable quantity of purple blood. In the same way in the egg, when the chick was formed and had increased in size, the heart too increased and acquired ventricles, which then began to receive and to transmit blood.
And this leads me to remark that he who inquires very particularly into this matter will not conclude that the heart, as a whole, is the primum vivens, ultimum moriens — the first part to live, the last to die — but rather its auricles, or the part which corresponds to the auricles in serpents, fishes, etc., which both lives before the heart and dies after it.
Nay, has not the blood itself or spirit an obscure palpitation inherent in it, which it has even appeared to me to retain after death? and it seems very questionable36 whether or not we are to say that life begins with the palpitation or beating of the heart. The seminal37 fluid of all animals — the prolific38 spirit, as Aristotle observed, leaves their body with a bound and like a living thing; and nature in death, as Aristotle6 further remarks, retracing39 her steps, reverts40 to where she had set out, and returns at the end of her course to the goal whence she had started. As animal generation proceeds from that which is not animal, entity41 from nonentity42, so, by a retrograde course, entity, by corruption43, is resolved into nonentity, whence that in animals, which was last created, fails first and that which was first, fails last.
I have also observed that almost all animals have truly a heart, not the larger creatures only, and those that have red blood, but the smaller, and pale-blooded ones also, such as slugs, snails44, scallops, shrimps46, crabs48, crayfish, and many others; nay, even in wasps49, hornets, and flies, I have, with the aid of a magnifying glass, and at the upper part of what is called the tail, both seen the heart pulsating myself, and shown it to many others.
But in the pale-blooded tribes the heart pulsates sluggishly50 and deliberately51, contracting slowly as in animals that are moribund52, a fact that may readily be seen in the snail45, whose heart will be found at the bottom of that orifice in the right side of the body which is seen to be opened and shut in the course of respiration53, and whence saliva is discharged, the incision54 being made in the upper aspect of the body, near the part which corresponds to the liver.
This, however, is to be observed: that in winter and the colder season, exsanguine animals, such as the snail, show no pulsation; they seem rather to live after the manner of vegetables, or of those other productions which are therefore designated plant-animals.
It is also to be noted that all animals which have a heart have also auricles, or something analogous55 to auricles; and, further, that whenever the heart has a double ventricle, there are always two auricles present, but not otherwise. If you turn to the production of the chick in ovo, however, you will find at first no more a vesicle or auricle, or pulsating drop of blood; it is only by and by, when the development has made some progress, that the heart is fashioned; even so in certain animals not destined56 to attain57 to the highest perfection in their organization, such as bees, wasps, snails, shrimps, crayfish, etc., we only find a certain pulsating vesicle, like a sort of red or white palpitating point, as the beginning or principle of their life.
We have a small shrimp47 in these countries, which is taken in the Thames and in the sea, the whole of whose body is transparent58; this creature, placed in a little water, has frequently afforded myself and particular friends an opportunity of observing the motions of the heart with the greatest distinctness, the external parts of the body presenting no obstacle to our view, but the heart being perceived as though it had been seen through a window.
I have also observed the first rudiments59 of the chick in the course of the fourth or fifth day of the incubation, in the guise60 of a little cloud, the shell having been removed and the egg immersed in clear tepid61 water. In the midst of the cloudlet in question there was a bloody62 point so small that it disappeared during the contraction and escaped the sight, but in the relaxation63 it reappeared again, red and like the point of a pin; so that betwixt the visible and invisible, betwixt being and not being, as it were, it gave by its pulses a kind of representation of the commencement of life.
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1 skilful | |
(=skillful)adj.灵巧的,熟练的 | |
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2 deference | |
n.尊重,顺从;敬意 | |
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3 simultaneously | |
adv.同时发生地,同时进行地 | |
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4 tardily | |
adv.缓慢 | |
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5 pulsating | |
adj.搏动的,脉冲的v.有节奏地舒张及收缩( pulsate的现在分词 );跳动;脉动;受(激情)震动 | |
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6 pulsate | |
v.有规律的跳动 | |
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7 contraction | |
n.缩略词,缩写式,害病 | |
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8 contractions | |
n.收缩( contraction的名词复数 );缩减;缩略词;(分娩时)子宫收缩 | |
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9 pulsation | |
n.脉搏,悸动,脉动;搏动性 | |
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10 unwillingly | |
adv.不情愿地 | |
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11 noted | |
adj.著名的,知名的 | |
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12 precisely | |
adv.恰好,正好,精确地,细致地 | |
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13 arteries | |
n.动脉( artery的名词复数 );干线,要道 | |
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14 distension | |
n.扩张,膨胀(distention) | |
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15 veins | |
n.纹理;矿脉( vein的名词复数 );静脉;叶脉;纹理 | |
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16 conspicuous | |
adj.明眼的,惹人注目的;炫耀的,摆阔气的 | |
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17 extremities | |
n.端点( extremity的名词复数 );尽头;手和足;极窘迫的境地 | |
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18 distended | |
v.(使)膨胀,肿胀( distend的过去式和过去分词 ) | |
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19 eel | |
n.鳗鲡 | |
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20 pulsates | |
v.有节奏地舒张及收缩( pulsate的第三人称单数 );跳动;脉动;受(激情)震动 | |
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21 nay | |
adv.不;n.反对票,投反对票者 | |
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22 peculiar | |
adj.古怪的,异常的;特殊的,特有的 | |
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23 tenacious | |
adj.顽强的,固执的,记忆力强的,粘的 | |
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24 radical | |
n.激进份子,原子团,根号;adj.根本的,激进的,彻底的 | |
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25 glutinous | |
adj.粘的,胶状的 | |
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26 sluggish | |
adj.懒惰的,迟钝的,无精打采的 | |
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27 soluble | |
adj.可溶的;可以解决的 | |
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28 faculty | |
n.才能;学院,系;(学院或系的)全体教学人员 | |
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29 eels | |
abbr. 电子发射器定位系统(=electronic emitter location system) | |
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30 saliva | |
n.唾液,口水 | |
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31 pulsated | |
v.有节奏地舒张及收缩( pulsate的过去式和过去分词 );跳动;脉动;受(激情)震动 | |
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32 imbued | |
v.使(某人/某事)充满或激起(感情等)( imbue的过去式和过去分词 );使充满;灌输;激发(强烈感情或品质等) | |
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33 lapse | |
n.过失,流逝,失效,抛弃信仰,间隔;vi.堕落,停止,失效,流逝;vt.使失效 | |
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34 distinguished | |
adj.卓越的,杰出的,著名的 | |
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35 apparently | |
adv.显然地;表面上,似乎 | |
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36 questionable | |
adj.可疑的,有问题的 | |
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37 seminal | |
adj.影响深远的;种子的 | |
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38 prolific | |
adj.丰富的,大量的;多产的,富有创造力的 | |
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39 retracing | |
v.折回( retrace的现在分词 );回忆;回顾;追溯 | |
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40 reverts | |
恢复( revert的第三人称单数 ); 重提; 回到…上; 归还 | |
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41 entity | |
n.实体,独立存在体,实际存在物 | |
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42 nonentity | |
n.无足轻重的人 | |
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43 corruption | |
n.腐败,堕落,贪污 | |
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44 snails | |
n.蜗牛;迟钝的人;蜗牛( snail的名词复数 ) | |
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45 snail | |
n.蜗牛 | |
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46 shrimps | |
n.虾,小虾( shrimp的名词复数 );矮小的人 | |
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47 shrimp | |
n.虾,小虾;矮小的人 | |
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48 crabs | |
n.蟹( crab的名词复数 );阴虱寄生病;蟹肉v.捕蟹( crab的第三人称单数 ) | |
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49 wasps | |
黄蜂( wasp的名词复数 ); 胡蜂; 易动怒的人; 刻毒的人 | |
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50 sluggishly | |
adv.懒惰地;缓慢地 | |
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51 deliberately | |
adv.审慎地;蓄意地;故意地 | |
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52 moribund | |
adj.即将结束的,垂死的 | |
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53 respiration | |
n.呼吸作用;一次呼吸;植物光合作用 | |
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54 incision | |
n.切口,切开 | |
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55 analogous | |
adj.相似的;类似的 | |
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56 destined | |
adj.命中注定的;(for)以…为目的地的 | |
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57 attain | |
vt.达到,获得,完成 | |
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58 transparent | |
adj.明显的,无疑的;透明的 | |
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59 rudiments | |
n.基础知识,入门 | |
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60 guise | |
n.外表,伪装的姿态 | |
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61 tepid | |
adj.微温的,温热的,不太热心的 | |
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62 bloody | |
adj.非常的的;流血的;残忍的;adv.很;vt.血染 | |
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63 relaxation | |
n.松弛,放松;休息;消遣;娱乐 | |
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