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VIVISECTION
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VIVISECTION , literally the cutting (sectio) of living (vivus) animals, a word which might be applied to all surgical operations whether practised upon the See also:lower animals or on See also:man . As conventionally used, however, it has exclusive reference to experiments upon the lower animals undertaken for the See also:advancement of medical sciences . There are a number of See also:people who, calling themselves See also:anti-vivisectionists, strongly See also:object to these experiments on the lower animals; and it must be conceded that the humane reasons which they advance against it can only be set aside as " sentimental " if considerations of a wider humanity can show that the arguments of the anti-vivisectionists really run See also:counter to human progress . The supporters of vivisection, properly considered, must not be confused with those who would make a barbarous use of this means of See also:research . What is at stake here is the right to use it properly and at all . It would be possible for See also:cruelty of an unnecessary See also:kind to result if the practice of vivisection were unrestricted; and the purpose of this See also:article is to give some See also:account of the method of experiments on animals as sanctioned by See also:law in the See also:United See also:Kingdom, and to justify that method by setting forth the See also:chief See also:historical discoveries that have been made by the help of vivisection . Such experiments have for their object the advancement of the sciences of See also:physiology and See also:pathology . From the earliest periods experimental vivisections have occasionally been practised, but before the days of anaesthetics it was difficult to execute them,•and not less difficult to draw conclusions . The invention of anaesthetics has greatly extended the See also:scope of the experimental method, because an See also:animal can be kept unconscious and quiet, without even a See also:quiver of a•muscle, during prolonged operations . Further, the introduction of the antiseptic method has made it possible to subject all tissues and regions of the See also:body to surgical interference, and this has also had the effect of increasing the possibilities of experimental research . In 1906 a See also:British Royal See also:Commission was appointed to inquire into the whole subject under the chairmanship of See also:Lord See also:Selby, on whose See also:death Mr A . J .
See also:Ram, K.C., took the See also:chair
.
The Commission sat from See also:October 1906 to See also: The act, therefore, was drafted with a view to physiology, without much concern for pathology, and without foreknowledge of bacteriology . At the time of See also:writing (191o), 95% of the experiments are inoculations . Every experiment must be made in a registered See also:place open to See also:government inspection . But inoculation experiments are sometimes permitted in non-registered places, for the immediate study of outbreaks of disease, or in circumstances which render it impracticable to use a registered place . Every experiment must be made under a See also:licence; and every application for a licence must be recommended by the signatures of two out of a small body of authorities specified in the act—presidents of certain learned See also:societies and professors of certain See also:universities and colleges . The word " experiment " is not allowed to See also:cover the use of more than one animal . Most experiments are made not under a licence alone, but under a licence plus one or more certificates, and the wording and working of these certificates must be clearly understood, because it is over them that the question arises as to the amount of See also:pain inflicted by these experiments . Under the licence alone, the animal must be kept under an anaesthetic during the whole of the experiment; and " if the pain is likely to continue after the effect of the anaesthetic has ceased, or if any serious injury has been inflicted on the animal," it must be killed forthwith under the anaesthetic . Thus, under the licence alone, it is impossible to make an inoculation; for the experiment consists, not in the introduction of the See also:needle under the skin, but in the observation of the results of the inoculation . A See also:guinea-See also:pig inoculated with tubercle cannot be kept under an anaesthetic till the disease appears . The disease is the experiment, and it is therefore an experiment made without an anaesthetic, and not authorized by the licence alone . Again, under the licence alone it would have been impossible to work out the See also:thyroid treatment of See also:myxoedema, or the facts of cerebral localization . For to remove the thyroid gland, or to remove a portion of the See also:surface of the See also:brain, is to inflict a serious injury on the animal . The operation is done under profound See also:anaesthesia—it would be impracticable otherwise; the See also:wound is treated and dressed by the antiseptic method—suppuration would invalidate the result . But a serious injury has been inflicted . Nevertheless, the animal must not be killed forthwith: the result must be watched . These and the like experiments cannot therefore be made under the licence alone . For the removal of such disabilities as these, the act empowers the See also:home secretary to allow certain certificates, to be held with the licence . They must be recommended by two signatures, and various restrictions are put upon them by the home secretary . On July s1, 1898, the home secretary was asked, in the See also:House of See also:Commons, what were the conditions and regulations attached by the Home See also:Office to licences and certificates; and he answered " The conditions are not always the same, but may vary according to the nature of the investigation . It is hardly possible, therefore, for me to See also:state all the conditions attached to licences and certificates . The most important conditions, however (besides the limitations as to place, time and number of experiments), and the conditions most frequently imposed, are those as to See also:reporting and the use of See also:antiseptics . The latter See also:condition is that the animals are to be treated with strict antiseptic precautions, and if these fail and pain results, they are to be killed Immediately under anaesthetics . The reporting conditions are, in brief, that a written See also:record, in a pre-scribed See also:form, is to be kept of every experiment, and is to be open for examination by the inspector; that a See also:report of all experiments is to be forwarded to the inspector; and that any published account of an experiment is to be transmitted to the secretary of state . Another condition requires the immediate destruction under anaesthetics of an animal in which severe pain has been induced, after the See also:main result of the experiment has been attained." The home secretary attaches to licences and certificates such endorsements as he thinks See also:fit . The See also:bare See also:text of the act, now See also:thirty-four years old, is a very different thing from the See also:administration of the act; and the present writer is in a position to say that the act is administered with See also:great strictness, under a careful See also:system of inquiry and reference . The certificates are distinguished as A, B, C, E, EE and F . Certificate D, which permitted the testing, by experiments, of " former discoveries alleged to have been made," has fallen into disuse . Certificate C permits experiments to be made by way of See also:illustration of lectures . They must be made under the provisions contained in the act as to the use of anaesthetics . Certificates E and EE permit experiments on See also:dogs or See also:cats; certificate F permits experiments on horses, asses or mules . These certificates are linked with Certificate A or Certificate B . It is See also:round these two certificates, A and B, that the controversy as to the pain caused by experiments on animals is maintained . Certificate A permits experiments to be made without anaesthesia . It is worded as follows: " Whereas A . B. of [here insert address and profession] has represented to us (i.e. two authorities) that he proposes, if duly authorized under the above-mentioned act, to perform on living animals certain experiments described below: We hereby certify that, in our See also:opinion, insensibility in the animal on which any such experiment may be performed cannot be produced by anaesthetics without necessarily frustrating the object of such experiment." All inoculations under the skin, all feeding experiments and the like, are scheduled under this certificate . They must be scheduled somehow: they cannot legally be made under a licence alone . Though the only See also:instrument used is a hypodermic needle, yet every inoculation is officially returned as an experiment, calculated to give pain, performed without an anaesthetic . It is for inoculations and the like experiments, and for them alone, and for nothing else, that Certificate A is allowed (or A linked with E or F) . This want of a See also:special certificate for inoculations, and this wresting of Certificate A for the purpose, have led to an erroneous belief that " cutting operations' are permitted by the act without an anaesthetic . But, as the home secretary said in See also:parliament, in March 1897, " Certificate A is never allowed except for inoculations and similar trivial operations, and in every See also:case a condition is attached to prevent unnecessary pain." And again he wrote in 1898, Such special certificates (dispensing with anaesthetics) are granted only for inoculations, feeding and similar procedures involving no cutting . The animal has to be killed under anaesthetics if it be in pain, so soon as the result of the experiment is ascertained." Certificate B permits the keeping alive of the animal after the initial operation of an experiment . It is worded as follows: " Whereas A . B. of [here insert address and profession] has represented to us (i.e. two authorities) that he proposes, if duly authorized under the above-mentioned act, to perform on living animals certain experiments described below, such animals being, during the whoie of the initial operation of such experiments, under the See also:influence of some anaesthetic of sufficient See also:power to prevent their feeling pain: We hereby certify that, in our opinion, the killing of the animal on which any such experiment is performed before it recovers from the influence of the anaesthetic administered to it would necessarily frustrate the object of such experiment." Certificate B (or B linked with EE or F) is used. for those experiments which consist in an operation plus subsequent observation of .the animal . The See also:section of a See also:nerve, the removal of a secretory See also:organ, the See also:establishment of a See also:fistula, the plastic surgery of the See also:intestine, the sub-dural method of inoculation—these and the like experiments are made under this certificate . We may take, to illustrate the use of Certificate B, See also:Horsley's observations on the thyroid gland . The removal of the gland was the initial operation; and this was performed under an anaesthetic, and with the antiseptic method . Then the animal was kept under observation: The experiment is neither the operation alone nor the observation alone, but the two together . The purpose of this certificate is set forth in the inspector's report for 1909 . " In the experiments performed under Certificate B, or B linked with EE, 1704 in number, the initial operations are performed under anaesthetics from the influence of which the animals are allowed to recover . The operations are required to be performed antiseptically, so, that the healing of the wounds shall, as far as possible, take place without pain . If the antiseptic precautions fail, and suppuration occurs, the animal is required to be killed . It is generally essential for the success of these experiments that the wounds should heal cleanly, and the surrounding parts remain in a healthy condition . After the healing of the wounds the animals are not necessarily, or even generally, in pain, since experiments involving the removal of important See also:organs, including portions of the brain, may be performed without giving rise to pain after the recovery from the operation; and after the section of a part of the See also:nervous system, the resulting degenerative changes are painless . In the event of a subsequent operation being necessary in an experiment performed under Certificate B, or B linked with EE, a condition is attached to the licence requiring all operative procedures to be carried out under anaesthetics of sufficient power to prevent the animal feeling pain; and no observations or stimulations of a See also:character to cause pain are allowed to be made without the animals being anaesthetized . In no case has a cutting operation more severe than a superficial venesection (the opening of a vein just under the skin) been allowed to be performed without anaesthetics." From this brief account of the chief provisions of the act, we come to consider the general method of experiments on animals in the United Kingdom, and the question of the infliction of pain on them . The figures for a representative See also:year may be given . The See also:total number of licensees in 19o9r in See also:England and See also:Scotland, was 483: of whom 135 performed no experiments during the year . The total number of experiments was 86,277, being 2357 less than in 1908 . They were made as follows : Under Licence alone . Certificate C . Certificate A . Certificates A+E Certificates A+F Certificate B Certificates B +EE Certificate F . . The experiments performed under Certificate A (or A+E, or A+F) were mostly inoculations; but a few were feeding experiments, or the administration of various substances by the mouth or by inhalation, or the See also:abstraction of See also:blood by puncture or by See also:simple venesection . Inoculations into deep parts, involving a preliminary incision, are required to be per-formed under anaesthetics (Certificate B) . " It will be seen," says the report for 1909, " that the operative procedures in experiments performed under Certificate A, without anaesthetics, are only such as are attended by no considerable, if appreciable, pain . The certificate is, in fact, not required to cover these proceedings, but to allow of the subsequent course of the experiment . The animals most used for inoculations are mice, rats, guinea-pigs and rabbits . It is not once in a thousand times that a See also:dog or a See also:cat is used for inoculation . The act of inoculation is not in itself painful . A small See also:area of the skin is carefully shaved and cleansed, that it may be aseptic, the hypodermic needle is sterilized and the method of hypodermic injection or of See also:vaccination is the same as it is in medical practice . "A guinea-pig that will See also:rest quietly in your hands before you commence to inject it, will remain perfectly quiet during the introduction of the needle under the skin; and the moment it is returned to the cage it resumes its interrupted feeding . See also:Arteries, See also:veins and most of the parts of the viscera are without the sense of See also:touch . We have actual See also:proof of this in what takes place when a See also:horse is bled for the purpose of obtaining curative serum . With a See also:sharp See also:lance a cut may be, made in the skin so quickly and easily that the animal does nothing more than twitch the skin-muscle of the See also:neck, or give his See also:head a shake, while of the further proceeding of introducing a hollow needle into the vein, the animal takes not the slightest See also:notice . Some horses, indeed, will stand perfectly quiet during the whole operation, munching a See also:carrot, nibbling at a wisp of See also:hay, or playing with a See also:button on the vest of the See also:groom See also:standing at its head." These sentences, written in the Medical See also:Magazine (See also:June 1898) by Dr See also:Sims Woodhead, See also:Professor of Pathology at See also:Cambridge, are sufficient evidence that inoculations and the like experiments are not painful at the time . In a few instances cultures of micro-organisms have been made in the anterior chamber, of the See also:eye, by the introduction of a needle behind the cornea . This might be thought painful, but See also:cocaine renders the surface of the eye wholly insensitive . Many operations of opfithalmic surgery are done under cocaine alone, and the anterior chamber of the eye is so far insensitive that a man may have blood or pus (hypopyon) in it, and hardly be conscious of the fact . The results of inoculation are in some cases negative, in others See also:positive; the positive results are, in the great majority of cases, not a See also:local See also:change, but a general infection which may end in recovery, or in death . The diseases thus induced may, in many cases, fairly be called painless—such are septicaemia in a See also:mouse, snake-venom in a See also:rat, and See also:malaria in a See also:sparrow . Rabbits affected with rabies do not suffer in the same way as dogs and some other animals, but become subject to a painless kind of See also:paralysis . It is probable that animals kept for inoculation have, on the whole, less pain than falls to the See also:lot of a like number of animals in a state of nature or in subjection to work: they are well fed and sheltered, and See also:escape the rapacity of larger animals, the inevitable cruelties of See also:sport, and the drudgery and sexual See also:mutilation that man inflicts on the higher domestic animals . The present writer has, of course, seen the mice that are used for the study of See also:cancer (Imperial Cancer Research Fund), and the guinea-pigs that are used at the See also:Lister See also:Institute for thetesting of the London See also:milk-See also:supply, lest the milk should convey tubercle . He did not see, among all the many animals, one that appeared to be suffering: See also:save that a very few of the mice were incommoded, or, if the word be applicable to mice, distressed, by large tumours . Of the guinea-pigs that had been inoculated, not one seemed to be in any pain . A nodule of tubercle, or a tuberculous gland, is painless in us, and therefore cannot be painful in a guinea-pig . It is not denied that the study of some diseases (See also:plague, See also:tetanus) causes some pain to rats and rabbits; but this pain is hardly to be compared with the pain and horror of these diseases in man . We come now to Certificate B . If it were lawful, under Certificate B, to make an incision under an anaesthetic, to See also:call this the " initial operation," and then, without an anaesthetic, to make painful experiments, through the incision, on the deeper structures, doubtless much pain might be inflicted under this certificate . But experiments of this kind can be, and are, made under the licence alone, the animal being kept under an anaesthetic all the time, and killed under it . " No experiments requiring anything of the nature of a surgical operation, or that would cause the infliction of an appreciable amount of pain, are allowed to be performed without an anaesthetic" (Inspector's Report for 1899) . " These certificates (B) are granted on condition that antiseptic precautions are used; and if these fail, and pain continues after the anaesthetics have ceased to operate, the animal is immediately killed painlessly" (See also:Letter from the Home Secretary, 1898) . Of experiments made under this certificate (which must be linked with Certificate EE for any experiment on a dog or a cat), three instances may be given here: an operation on the brain, a removal of part or the whole of a secreting gland, and the establishment of a fistula . It is to be noted that, for these and the like operations, profound anaesthesia and the strict observance of the antiseptic method are matters of See also:absolute See also:necessity for the success of the experiment: the operation could not be performed without anaesthesia; and the experiment would come to nothing if the wound suppurated . It is to be noted, also, that these operations are such as are performed in surgery for the saving of See also:life or for the See also:relief of pain .
As to operations on the brain, it must be remembered that the surface of the brain is not sensitive
.
Therefore the removal or destruction, of a portion of the surface of the brain, or the See also:division of some See also:tract of central nervous See also:tissue, though it might See also:entail some loss of power or of See also:control, does not, cause pain: a wound of the brain is painless
.
Tension within the ;See also:cranial cavity, as in cases of cerebral See also:tumour or cerebral See also:abscess, may indeed cause great pain; and, if the aseptic method failed, in an experiment, inflammation and tension would ensue: in that case the animal must be killed
.
The removal of part or the whole of a secreting gland (e.g. the thyroid, the See also:spleen, the See also:kidney) is performed by the same methods, and with the same precautions, as in human surgery
.
Profound anaesthesia, and the use of a strict antiseptic See also:procedure, are of absolute necessity
.
The skin over the part to be removed must be shaved and carefully cleansed for the operation; the See also:instruments, See also:sponges and ligatures must be sterile, not capable of infecting the wound; and when the operation is over, the wound must be carefully closed with sutures, and See also:left to heal under a proper surgical dressing
.
The establishment of a fistula, again, is an operation practised, as a See also:matter of course, in large See also:numbers of surgical cases
.
The See also:stomach, the See also:gall-See also:bladder, the large intestine, are opened for the relief of obstruction, and kept open, either for a time or permanently, according to the nature of the case
.
Under anaesthesia, the organ that is to be opened is exposed through an incision made through the structures overlying it, and is secured in the wound by means of See also:fine sutures
.
Then, when it has become adherent there, it is opened by an incision made into it; no anaesthetic is needed for this purpose, because' these See also:internal organs are so unlike the skin in sensitiveness that an incision is hardly See also:felt : the patient may say that he " felt a -prick," or he may be wholly unconscious that anything has been done
.
A
1,980
196
81,566
595
1,385
319
8
fistula thus established is not afterward painful, though there may be some discomfort now and again
.
The classical instance is the case of See also:Alexis St See also: He let Dr See also:Beaumont make experiments on him for nine years: " During the whole of these periods, from the See also:spring of 1824 to the present time (1833), he has enjoyed general See also:good See also:health . . . active, athletic and vigorous; exercising, eating and drinking like other healthy and active people . For the last four months he has been unusually plethoric and robust, though constantly subjected to a continuous See also:series of experiments on the interior of the stomach; allowing to be introduced or taken out at the See also:aperture different kinds of See also:food, drinks, elastic catheters, thermometer tubes, gastric juice. chyme, &c., almost daily, and sometimes hourly . Such have been this man's condition and circumstances for several years past; and he now enjoys the most perfect health and constitutional soundness, with every See also:function of the system in full force and vigour " (Beaumont, Experiments and Observations on the Gastric Juice, 1838) . We come now to the question, What anaesthetics are used in these experiments, and are they properly administered ? The anaesthetics used are—(r) See also:chloroform, See also:ether, or a mixture containing chloroform and ether; (2) morphia, See also:chloral, See also:urethane . It is sometimes said that morphia is not an anaesthetic . That depends on the quantity given . Not a See also:month passes in this See also:country without somebody killing himself or herself with morphia or chloral . They See also:die profoundly anaesthetized: they cannot,be roused; even the pain of a strong electric See also:shock is not enough to rouse them . So it is with animals . The doses given to them are enormous and produce See also:complete insensibility .
On this point the evidence given before the Royal Commission of 1906-8 by Mr Thane, Professor Schafer, See also:Sir See also:Lauder See also:Brunton, Sir See also: The effect of that is, that the dog becomes sleepy and stupid, and then sometimes it will lie down quietly, and if it is very sleepy you can put a See also:mask over its See also:nose containing the chloroform, alcohol and ether mixture, which it takes quite quietly . If, at the time one wants to begin the operation, the animal is not fully under the influence of morphia —if it still seems restless—it is put in a See also:box, and there it has some See also:wool saturated with the A.C.E. mixture put in the box . The See also:air gradually gets saturated, the dog gets more and more sleepy, and finally subsides at the bottom of the box." A few words must be said here about curare . It was said, some years ago, by an opponent of experiments on animals, that " curare is used daily throughout England," whereas, it is seldom used at all, and is never used alone in any sort or kind of operation on any animal in this country: in every such case a recognized anaesthetic must be given, and is given . In large doses curare not only abolishes the See also:movement of the voluntary muscles,. but also acts as an anaesthetic: in small doses it acts only on the voluntarymuscles, i.e. on the endings of the motor nerves going to these muscles . For example, suppose that the object of the experiment is to observe and record the action of a nerve on the contraction of certain blood vessels . The nerve gives off some branches to muscles, and other branches to blood vessels . If the animal be anaesthetized, and the nerve. stimulated, muscles and vessels will both See also:contract; but, if curare be given, as well as an anaesthetic, the vessels alone will contract, without the muscles: for curare does not act on the endings of motor nerves going to blood vessels . But, as a See also:practical matter, curare is very hard to obtain, and is often impure, and is very seldom used . One of the inspectors said to the Royal Commission that he had once seen it used, fifteen years ago . Professor Gotch said that he had not used it, in his own work, for twenty years . Professor Schafer said that he had not used it for years . And Sir Lauder Brunton said that he did not think he had used it at all since the passing of the act of 1876 . The fear that, in a case where curare was being used, the effect of the anaesthetic might " pass off," and the animal be left under curare alone, is not reasonable . The dosage and administration of anaesthetics is not left to See also:chance . If, for example, an animal is receiving a definite percentage of chloroform vapour, it is of necessity under the influence of the chloroform: and the anaesthesia will gradually become not less but more profound . (See the evidence given before the Royal Commission by Professor See also:Langley and Professor See also:Waller.) It may be interesting to compare the pain, or death, or discomfort among 86,277 animals used for experiments in Great See also:Britain in 1909, with the pain, or death, or discomfort of an equal number of the same kinds of animals, either in a state of nature, or kept for sport, or used for the service of human profit or amusement . But it would be outside the purpose of this article to describe the cruelties which are inseparable from sport, and from the killing of animals for food, and from See also:fashion; neither is this the place to describe the millions of mutilations which are practised on domestic animals by farmers and breeders . As one of the Royal Commissioners recently said, the farmyards, at certain times of the year, simply " seethe with vivisection." The number of animals wounded in sport, or in traps, cannot be guessed . Against this, vast amount of suffering we have to put an estimate of the condition of 86,277 animals used for medical See also:science . Ninety-five per cent. of them were used for inoculation . In many of these inoculations the result was negative: the animal did not take any disease, and thus did not suffer any pain . In many more, e.g. cancer in mice, tubercle in guinea-pigs, the pain or discomfort, if any, may fairly be called trivial or inconsiderable . It could hardly be said that these small animals suffer much more than an equal number of the same kind of animals kept in little cages to amuse See also:children . There remain 3888 animals which were submitted to operation under an anaesthetic . In the greater number of these cases the animal was killed then and there under the anaesthetic, without recovering consciousness . In the remaining cases the animal was allowed to recover, and to be kept for observation; but no further observation of any kind, which could cause pain, was allowed to be made on it, unless it were again placed under an anaesthetic . Many of these cases, thus allowed to recover after an operation, may fairly be compared to an equal number of domestic animals after one of the formal operations of veterinary surgery . These observations made under Certificate B form but a very small proportion of the total number of experiments on animals in the United Kingdom; and they have led, in See also:recent years; to discoveries of the very utmost importance for human life and health . II . SCIENTIFIC RESULTS.—We come now to consider the results of experiments on animals, but we must remember that not we alone, but animals also, owe a great See also:debt to them . Great epizootic diseases like See also:anthrax, See also:swine-See also:fever, chicken See also:cholera, silkworm disease, pleuro-See also:pneumonia, See also:glanders, See also:Texas See also:cattle fever, blackleg, See also:tuberculosis in cattle, have killed yearly millions of animals, and have been brought under better control by these experiments . The advantages that have been obtained for man may be arranged under two heads—(A) :Physiology, (B) Pathology, Bacteriology and See also:Therapeutics . A . PHYSIOLOGY 1 . The Blood.—See also:Galen (A.D . 131) confuted the See also:doctrine of Erasistratus, that the arteries contained ,rv€Gµa, the breath of life, proving by experiment that they contain blood . " Ourselves, having tied the exposed arteries above and below, opened them, and showed that they were indeed full of blood." Realdus See also:Columbus (1559), though he did not discover the general or " systematic " circulation of the blood, yet seems to have discovered, by experiment, the pulmonary circulation . " The blood is carried through the pulmonary artery to the See also:lung, and there is attenuated; thence, mixed with air, it is carried through the pulmonary vein to the left See also:side of the See also:heart . Which thing no man hitherto has noted or left on record, though it is most worthy of the observance of all men .... And this is as true as truth itself; for if you will look not only in the dead body but also in the living animal, you will always find this pulmonary vein full of blood, which assuredly it would not be if it were designed only for air and vapours ... . Verily I pray you, 0 candid reader, studious of authority, but more studious of truth, to make experiment on animals . You will find the pulmonary vein full of blood, not air or uligo, as these men call it, See also:God help them." Harvey's See also:treatise De Motu Cordis et Sanguinis in Animalibus was published at See also:Frankfort in 1621 . It begins thus: " When by many dissections of living animals, as they came to See also:hand,—Cum multis vivorum dissectionibus, uti ad manum dabantur, —I first gave myself to observing how I might discover, with my own eyes, and not from books and the writings of other men, the use and purpose of the movement of the heart in animals, forthwith I found the matter hard indeed and full of difficulty; so that I began to think, with Frascatorius, that the movement of. the heart was known to God alone . . . . At last, having daily used greater disquisition and See also:diligence, by frequent examination of many and various living animals—multa frequenter et See also:varia animalia viva introspiciendo—I came to believe that I had succeeded, and had escaped and got out of this See also:labyrinth, and therewith had discovered what I desired, the movement and use of the heart and the arteries . And from that time, not only to my See also:friends but also in public in my anatomical lectures, after the manner of the See also:Academy, I did not fear to set forth my opinion in this matter." Here, and again at the end of the See also:Preface, and again in the eighth See also:chapter of the De Motu, he puts his experiments in the very foreground of the See also:argument . Take the headings of his first four chapters: 1 . 
Causae, quibus ad scribendum auctor permotus fuerit . 2 . Ex vivorum dissectione, qualis fit cordis motus . 3 . Arteriarum motus qualis, ex vivorum dissectione . 4 . Moms cordis et auricularum qualis, ex vivorum dissectione . He had, of course, help from other See also: |