 section one of fathers of biology this is a LibriVox recording all LibriVox recordings are in the public domain for more information or to volunteer please visit LibriVox.org recording by Avahi in November 2009 fathers of biology by Charles Mcgray preface it is hoped that the account given in the following pages of the lives of five great naturalists may not be found devoid of interest the work of each one of them marked a definite advance in the science of biology there is often among students of anatomy and physiology a tendency to imagine that the facts with which they are now being made familiar have all been established by recent observation and experiment but even the slight knowledge of the history of biology which may be obtained from a perusal of this little book will show that so far from such being the case this branch of science is of venerable antiquity and further if in the place of this misconception a desire is aroused in the reader for a fuller acquaintance with the writings of the early anatomists the chief aim of the author will have been fulfilled chapter 1 hypothesis owing to the lapse of centuries very little is known with certainty of the life of Hippocrates who was called with affectionate veneration by his successors the divine old man and who has been justly known to posterity as the father of medicine he was probably born about 470 BC and according to all accounts appears to have reached the advanced age of 90 years or more he must therefore have lived during a period of Greek history which was characterized by great intellectual activity for he had as his contemporaries Pericles the famous statesman the poets Aeschylus, Sophocles, Euripides, Aristophanes and Pindar the philosopher Socrates with his disciples Xenophon and Plato the historians Herodotus and Thucydides and Phidias the unrivaled sculptor in the island of Kos where he was born stood one of the most celebrated of the temples of Escolapius and in this temple because he was descended from the Asklepia day Hippocrates inherited from his forefathers an important position among the Asklepia the habit of physical observation and even manual training in dissection were imparted traditionally from father to son from the earliest years thus serving as a preparation for medical practice when there were no written treatises to study although Hippocrates at first studied medicine under his father he had afterwards for his teachers Gorgias and Democritus both of classic fame and Herodicus who is known as the first person who applied gymnastic exercises to the cure of diseases the Asklepians or temples of health were erected in various parts of Greece as receptables for invalids who were in the habit of resorting to them to seek the assistance of the God these temples were mostly situated in the neighborhood of medicinal springs and each devotee at his entrance was made to undergo a regular course of bathing and purification probably his diet was also carefully attended to and at the same time his imagination was worked upon by music and religious ceremonies on his departure the restored patient usually showed his gratitude by presenting to the temple votive tablets setting forth the circumstances of his peculiar case the value of these to men about to enter on medical studies can be readily understood and it was to such treasures of recorded observations collected during several generations that Hippocrates had excess from the commencement of his career owing to the peculiar constitution of the Asklepians medical and priestly pursuits had before the time of Hippocrates become combined and consequently although rational means were to a certain extent applied to the cure of diseases the more common practice was to resort chiefly to superstitious moods of working upon the imagination it is not surprising therefore to find that every sickness especially epidemics and plagues were attributed to the anger of some offended God and that penance and supplications often took the place of personal and domestic cleanliness fresh air and light it was Hippocrates who emancipated medicine from the thrall them of superstition and in this way rested the practice of his art from the monopoly of the priests in his treatise on the sacred disease possibly epilepsy he discusses the controversial question whether or not this disease was an inflection from the gods and he decidedly maintains that there is no such a thing as a sacred disease for all diseases arise from natural causes and no one can be ascribed to the gods more than another he points out that it is simply because this disease is unlike other diseases that men have come to regard its causes divine and yet it is not really more wonderful than the paroxysms of fevers and many other diseases not thought sacred he exposes the cunning of the imposters who pretend to cure man by purifications and spells who give themselves out as being excessively religious and is knowing more than other people and he argues that whoever is able by purifications and conjurings to drive away such an affection will be able by other practices to excite it and according to this view its divine nature is entirely done away with neither truly he continues do I counted a worthy opinion to hold that the body of a man is polluted by the divinity the most impure by the most holy for where it defiled or did it suffer from any other thing it would be like to be purified and sanctified rather than polluted by the divinity as an additional argument against the cause being divine he adduces the fact that this disease is hereditary like other diseases and that it attacks persons of a peculiar temperament namely the phlegmatic but not the bilious and yet if it were really more divine than the others he just adds it ought to be fall all alike again speaking of a disease common among the Scythians Hi Pocrates remarks that the people attributed it to a God but that to me it appears that such affections are just as much divine as all others are and that no one disease is either more divine or more human than another but that all are alike divine for that each has its own nature and that no one arises without a natural cause from this it will be seen that Hi Pocrates regarded all phenomena as at once divine and scientifically determinable in this respect it is interesting to compare him with one of his most illustrious contemporaries namely with Socrates who distributed phenomena into two classes one were in the connection of antecedent and consequent was invariable and a certain able by human study and wearing therefore future results were accessible to a well-instructed foresight the other which the gods had reserved for themselves and their unconditional agency wherein there was no invariable or a certain able sequence and whether result could only be foreknown by some omen or prophecy or other special inspired communication from themselves each of these classes was essentially distinct and required to be looked at and dealt with in a manner radically incompatible with the other physics and astronomy in the opinion of Socrates belong to the divine class of phenomena in which human research was insane fruitless and impious Hi Pocrates divided the causes of diseases into two classes the one comprehending the influence of seasons climates water situation and the like the other consisting of such causes as the amount and kind of food and exercise in which each individual indulges he considered that while heat and cold moisture and dryness succeeded one another throughout the year the human body underwent certain analogous changes which influenced the diseases of the period with regard to the second class of causes producing diseases he attributed many disorders to a vicious system of diet for excessive and defective diet he considered to be equally injurious in his medical doctrines Hi Pocrates starts with the axiom that the body is composed of the four elements air earth fire and water from these the four fluids or humors namely blood phlegm yellow bile and black bile are formed health is the result of a right condition and proper proportion of these humors disease being due to changes in their quality or distribution thus inflammation is regarded as the passing of blood into parts not previously containing it in the course of it is order proceeding favorably these humors undergo spontaneous changes in quality this process is spoken of as caution and is the sign of returning health as preparing the way for the expulsion of the morbid matters a state described as the crisis these crisis have a tendency to occur at certain periods which are hence called critical days as the critical days answer to the periods of the process of caution they are to be watched with anxiety and the actual condition of the patient at these times is to be compared with the state which it was expected he ought to show from these observations the physician may predict the course which the remainder of the disease will probably take and the right suggestions as to the practice to be followed in order to assist nature in her operations Hi Pocrates does appears to have studied the natural history of diseases as stated above his practice was to watch the manner in which the humors were undergoing the fermenting coction the phenomena displayed in the critical days and the aspect and nature of the critical discharge is not to attempt to check the process going on but simply to assist the natural operation his principles and practice were based on the theory of the existence of restoring essence or faces penetrating through all creation the agent which is constantly striving to preserve all things in the natural state and to restore them when they are preternaturally deranged in the management of this this media tricks not to re the art of the physician consisted attention therefore to regimen and diet was the principal remedy Hi Pocrates employed. Nevertheless, he did not hesitate when he considered that occasion required to administer such a powerful drug as hellebore in large doses. The writings which are extant under the names of Hi Pocrates cannot all be ascribed to him many were doubtless written by his family his descendants or his pupils. Others are productions of the Alexandrian school some of these being considered by critics as willful forgeries the high prices paid by the Ptolemies of books of reputation probably having acted as inducements to such fraud. The following works have generally been admitted as genuine one on airs waters and places to on ancient medicine three on the prognostics for on the treatment in acute diseases five on epidemics books one and three six on the wounds of the head seven on the articulations eight on fractures nine on the instruments of reduction ten the aphorisms seven books 11 the oath the works on fractures on the articulations on injuries to the head and on the instruments of reduction deal with anatomical or surgical matters and exhibit a remarkable knowledge of osteology and anatomy generally. It has sometimes been doubted if Hi Pocrates could ever have had opportunities of gaining this knowledge from their sections of the human body for it has been thought that the feeling of the age was diametrically opposed to such a practice and that Hi Pocrates would not have dared to violate this feeling. The language used however in some passages in the work on the articulations seems to put the matter beyond doubt. Thus he says in one place but if one will strip the point of the shoulder of the fleshy parts and where the muscle extends and also lay bare the tendon that goes from the armpit and clavicle to the breast etc. and again further on in the same treaties. It is evident then that such a case could not be reduced either by succusion or by any other method unless one were to cut open the patient and then having introduced the hand into one of the great cavities were to push outwards from within which one might do in the dead body but not at all in the living. His descriptions of the vertebrae with all their processes and ligaments as well as his account of the general characters of the internal viscera would not have been as free from error as they are if he had derived all his knowledge from the dissection of the inferior animals. Moreover it is indisputable that within less than a hundred years from the death of Hi Pocrates the human body was openly dissected in the schools of Alexandria. Nay further that even the vivisection of condemned criminals was not uncommon. It would be unreasonable to suppose that such a practice as the former sprang up suddenly under the pathologies and it seems therefore highly probable that it was known and tolerated in the time of Hi Pocrates. It is not surprising when we remember the rude appliances and methods which then obtained that in his knowledge of minute anatomy Hi Pocrates should compare unfavorably with anatomists of the present day. Of histology and such other subjects as could not be brought within his direct personal observation the knowledge of Hi Pocrates was necessarily defective. Thus he wrote of the tissues without distinguishing them confusing arteries veins and nerves and speaking of muscles vaguely as flesh but with matters within the reach of the ancient physician's own careful observation the case is very different. This is well shown in his wonderful chapter on the clubfoot in which he not only states correctly the true nature of the malformation but gives some very sensible directions for rectifying the deformity in early life. When human strength was not sufficient to restore a displaced limb he skillfully availed himself of all the mechanical powers which were then known. He does not appear to have been acquainted with the use of polys for the purpose but the axels which he describes as being attached to the bench which bears his name scum num Hi Pocrates must have been quite capable of exercising the force required. The work called the aphorisms which was probably written in the old age of Hi Pocrates consists of more than 400 short pithy sentences setting forth the principles of medicine physiology and natural philosophy. A large number of these sentences are evidently taken from the author's other works especially those on air etc on prognostics and on the articulations. They embody the result of a vast amount of observation and reflection and the majority of them have been confirmed by the experience of 2000 years. A proof of the high esteem in which they have always been held is furnished by the fact that they have been translated into all the languages of the civilized world among others into Hebrew Arabic Latin English Dutch Italian German and French. The following are a few examples of these aphorisms. Spontaneous lassitude indicates disease. Old people on the whole have fewer complaints than the young but those chronic diseases which do befall them generally never leave them. Persons who have sudden and violent attacks of fainting without any obvious cause die suddenly. Of the constitutions of the year the dry upon the whole are more healthy than the rainy and attended with less mortality. Ftises most commonly occurs between the ages of 18 and 35 years. If one gives to a person in fever the same food which is given to a person in good health what is strength to the one is disease to the other. Such food as is most grateful though not so wholesome is to prefer to that which is better but distasteful. Life is short and the art long the opportunity fleeting experience fallacious and judgment difficult. The physician must not only do his duty himself but must also make the patient the attendance and the externals cooperate. Hypocrities appears to have traveled a great deal and to have practiced his art in many places far distant from his native island. A few traditions of what he did during his long life remain but differences of opinion exist as to the truth of these stories. Thus one story says that when Perticus the king of Macedonia was supposed to be dying of consumption hypocrites discovered the disorder to be love sickness and speedily affected a cure. The details of this story scarcely seem to be worthy of credence more especially as similar legends have been told of entirely different persons belonging to widely different times. There are however some reasons for believing that Hippocrates visited the Macedonian court in the exercise of his professional duties for he mentions in the course of his writings among places which he had visited several which were situated in Macedonia and further his son Tessalus appears to have afterwards been caught physician to Achelaus king of Macedonia. Another story connects the name of Hippocrates with the great plague which occurred at Athens in the time of the Peloponnesian war. It is said that Hippocrates advised the lighting of great fires with wood of some aromatic kind probably some species of pine. These being kindled all about the city state the progress of the pestilence others besides Hippocrates are however famous for having successfully adopted this practice. A third legend states that the king of Persia pursuing the plan which in the two celebrated instances of Temistocles and Pausanias have proved successful of attracting to his side the most distinguished persons in Greece wrote to Hippocrates asking him to pay a visit to his court and that Hippocrates refused to go. Although the story is discarded by many scholars it is worthy of note that Stesias a kinsman and contemporary of Hippocrates is mentioned by Sinophon in the Anabasis as being in the service of the king of Persia and with regard to the refusal of the venerable physician to comply with the king's request one cannot lose sight of the fact that such refusal was the only course consistent with the opinions he professed of a monarchical form of government. After his various travels Hippocrates as seems to be pretty generally admitted spent the later portion of his life in Tessaly and died at Larissa at a very advanced age. It is difficult to speak of the skill and painstaking perseverance of Hippocrates in terms which shall not appear exaggerated and extravagant. His method of cultivating medicine was in the true spirit of the inductive philosophy. His descriptions were all derived from careful observations of its phenomena and as a result the greater number of his deductions have stood unscathed the test of 20 centuries. Still more difficult is it to speak with moderation of the candor which impelled Hippocrates to confess errors into which in his earlier practice he had fallen or of that freedom from superstition which entitled him to be spoken of as a man who knew not how to deceive or be deceived. Kitam fallere kwam falli nested or lastly of the purity of character and true nobility of soul which are brought so distinctly to light in the words of the oath translated below. I swear by Apollo the physician and Asculapius and I call Hygia and Panacea and all the gods and goddesses to witness that to the best of my power and judgment I will keep this oath and this contract to wit to hold him who taught me this art equally dear to me as my parents to share my substance with him to supply him if he is in need of the necessaries of life to regard his offspring in the same light as my own brothers and to teach them this art if they shall desire to learn it without fear or contract to impart the precepts the oral teaching and all the rest of the instruction to my own sons and to the sons of my teacher and to pupils who have been bound to me by contract and who have been sworn according to the law of medicine. I will adopt that system of regimen which according to my ability and judgment I consider for the benefit of my patients and will protect them from everything noxious and injurious. I will give no deadly medicine to anyone even if asked nor will I give any such counsel and similarly I will not give to a woman the means of procuring an abortion. With purity and with holiness I will pass my life and practice my art. Into whatever houses I enter I will go into them for the benefit of the sick keeping myself aloof from every voluntary act of injustice and corruption and lust. Whatever in the course of my professional practice or outside of it I see or hear which ought not to be spread abroad I will not divulge as reckoning that all such should be kept secret. If I continue to observe this oath and to keep it in violet may it be mine to enjoy life and the practice of the art respected among all men forever but should I violate this oath and forswear myself may the reverse be my lot. About the time that Hippocrates died Aristotle who may be regarded as the founder of the science of natural history was born BC 384 in Stegira an unimportant helenic colony in Thrace near the Macedonian frontier. His father was a distinguished physician and like Hippocrates boasted descent from the Asclepiodae the importance attached by the Asclepiodes to the habit of physical observation which has already been referred to in the life of Hippocrates secured for Aristotle from his earliest years that familiarity with biological studies which is so clearly evident in many of his works. Both parents of Aristotle died when their son was still a youth and in consequence of this he went to reside with Proxenus a native of Atarnaeus who had settled at Stegira. Subsequently he went to Athens as joined the school of Plato. Here he remained for about 20 years and applied himself to study with such energy that he became preeminent even in that distinguished band of philosophers. He is said to have been spoken of by Plato as the intellect of the school and to have been compared by him to a spirited cult that required the application of the rain to restrain its ardour. Aristotle probably wrote at this time some philosophical work the fame of which reached the ears of Philip king of Macedonia and added to the reputation which the young philosopher had already made with that monarch for Philip is said to have written to him on the occasion of Alexander's birth BC 356. King Philip of Macedonia to Aristotle greeting know that a son has been born to me. I thank the gods not so much that they have given him to me as that they have permitted him to be born in the time of Aristotle. I hope that thou wilt form him to be a king worthy to succeed me and to rule the Macedonians. After the death of Plato which occurred in 347 BC Aristotle quitted Athens and went to Atarnaeus where he stayed with Hermes who was then despot of that town. Hermes was a remarkable man who from being a slave had contrived to raise himself to the supreme power. He had been at Athens and had heard Plato's lectures and had there formed a friendship for Aristotle. With this man the philosopher remained for three years and was then compelled suddenly to seek refuge in Medellin owing to the perfidious murder of Hermes. The latter was decoyed out of the town by the Persian general, seized and sent prisoner Atarch Xerxes by whom he was hanged as a rebel. On leaving Atarnaeus Aristotle took with him a niece of Hermes named Pithies whom he afterwards married. She died young, leaving an infant daughter. Two or three years after this Aristotle became tutor to Alexander who was then about 13 years old. The philosopher seems to have been a favorite with both the king and the prince and in gratitude for his services Philip rebuilt Stagira and restored it to its former inhabitants who had either been dispersed or carried into slavery. The king is said also to have established there a school for Aristotle. The high respect in which Alexander held his teacher is expressed in his saying that he honored him no less than his own father for while to one he owed life to the other he owed all that made life valuable. In 336 BC Alexander who was then only about 20 years of age became king and Aristotle soon afterwards quitted Macedonia and took up his residence in Athens once more after an absence of about 12 years. Here he opened a school in the Lyceum a gymnasium on the eastern side of the city and continued his work there for about 12 years during which time Alexander was making his brilliant conquests. The lectures were given for the most part while walking in the garden and in consequence perhaps of this the sect received the name of the peripatetics. The discourses were of two kinds the esoteric or abstruse and the exoteric or familiar the former being delivered to the more advanced pupils only. During the greater part of this time Aristotle kept up correspondence with Alexander who is said to have placed at his disposal thousands of men who were busily employed in collecting objects and in making observations for the completion of the philosophers' zoological researches. Alexander is moreover said to have given the philosopher eight hundred talents for the same purpose. In spite of these marks of friendship and respect Alexander who was fast becoming intoxicated with success and corrupted by Asiatic influences gradually called in his attachment towards Aristotle. This may have been hastened by several causes and, among others, by the freedom of speech and republican opinions of Callisthenes, a kinsman and disciple of Aristotle who had been by the latter's influence appointed to attend on Alexander. Callisthenes proved so unpopular that the king seems to have availed himself readily of the first plausible pretext for putting him to death and to have threatened his former friend and teacher with a similar punishment. The latter, for his part, probably had a deep feeling of resentment towards the destroyer of his kinsmen. Meanwhile the Athenians knew nothing of these altered relations between Aristotle and Alexander, but continued to regard the philosopher as thoroughly imbued with kingly notions, in spite of his writings being quite to the contrary, so that he was an object of suspicion and dislike to the Athenian patriots. Nevertheless, as long as Alexander was alive, Aristotle was safe from molestation. As soon, however, as Alexander's death became known, the anti-Macedonian feeling of the Athenians burst forth and found a victim in the philosopher. A charge of impiety was brought against him. It was alleged that he had paid divine honors to his wife Pythias and to his friend Hermias. Now, for the latter, a eunuch who, from the rank of a slave, had raised himself to the position of despot over a free Grecian community, so far from coupling his name, as Aristotle had done in his hymn, with the greater personages of Hellenic mythology, the Athenian public felt that no contempt was too bitter. To escape the storm, the philosopher retired to Chalcis in Ubelia, then under Garrison by Antipater, the governor of Macedonia, remarking in a letter written afterwards that he did so in order that the Athenians might not have the opportunity of sinning a second time against philosophy, the illusion being, of course, to the fate of Socrates. He probably intended to return to Athens again so soon as the political troubles had abated, but in September 322 B.C. he died at Chalcis. An overraught mind, coupled with indigestion and weakness of the stomach, from which he had long suffered, was most probably the cause of death. Some of his detractors, however, have asserted that he took poison, and others that he drowned himself in the Ubeian Euripus. It is not easy to arrive at a just estimate of the character of Aristotle. By some of his successes, he has been reproached within gratitude to his teacher, Plato, with servility to Macedonian power, and with love of costly display. How far these two last charges are due to personal slander, it is impossible to say. The only ground for the first charge is that he criticised adversely some of Plato's doctrines. The manuscripts of Aristotle's works pass through many vicissitudes. At the death of the philosopher, they were bequeathed to Theophrastus, who continued chief of the peripatetic school for 35 years. Theophrastus left them, with his own works, to a philosophical friend and pupil, Nelaus, who conveyed them from Athens to his residence at Skepsis in Asia Minor. About thirty or forty years after the death of Theophrastus, the kings of Pergamus, to whom the city of Skepsis belonged, began collecting books to form a library on the Alexandrian plan. This led the heirs of Nelaus to conceal their literary treasures in a cellar, and there the manuscripts remained for nearly a century and a half, exposed to injury from damp and worms. At length they were sold to Apelicon, a resident at Athens, who was attached to the peripatetic sect. Many of the manuscripts were imperfect, having become worm-eaten or illegible. These defects Apelicon attempted to remedy, but being a lover of books rather than a philosopher, he performed the work somewhat unskillfully. When Athens was taken by Scylla, 86 BC, the library of Apelicon was transported to Rome. There, various literary Greeks obtained access to it, and among others, Tyrannion, a grammarian and friend of Cicero, did good service in the work of correction, Andronicus of Rhodes afterwards arranged the whole into sections, and published the manuscripts with a tabulated list. The three principal works on biology which are extant are The History of Animals, On the Parts of Animals, On the Generation of Animals. The other biological works are On the Motion of Animals, On Respiration, Parva Naturalia, a series of essays which are planned to form an entire work on Sense and the Sensible. The History of Animals is the largest and most important of Aristotle's works on biology. It contains a vast amount of information, not very methodically arranged, and spoiled by the occurrence here and there of very gross errors. It consists of nine books. The first book opens with the division of the body into similar and dissimilar parts, besides thus differing in their parts. Animals also differ in their mode of life, their actions, and dispositions. Thus some are aquatic others terrestrial. Of the former, some breathe water, others air, and some neither. Of aquatic animals, some inhabit the sea, and others, rivers, lakes, or marshes. Again, some animals are locomotive, and others are stationary. Some follow a leader, others act independently. Various differences are in this way pointed out, and there is no lack of illustration and detail, but a suspicion is excited that the generalizations are sometimes based upon insufficient facts. The book closes with a description of the different parts of the human body, both internal and external. In speaking of the ear, Aristotle seems to have been aware of what we now call the Eustachian tube, for he says, There is no passage from the ear into the brain, but there is to the roof of the mouth. In the second book, he passes on to describe the organs of animals. The animals are dealt with in groups, viviparous and oviparous quadrupeds, fish, serpents, birds, etc. The ape, elephant, chameleon, and some others are especially noted. The third book continues the description of the internal organs, references which are made to a diagram by letters A, B, C, D, show that the work was originally illustrated. At the close of this book, Aristotle has some remarks on milk, and mentions the occasional appearance of milk in male animals. He speaks of a male goat at Lemnos, which yielded so much that cakes of cheese were made from it. Similar instances of this phenomenon have been recorded by Humboldt, Burdach, Joffreus and Ilière, and others. In the first four chapters of the fourth book, the anatomy of the invertebrata is dealt with, and the accounts given of certain molusca and crustacea are very careful and minute. The rest of the book is devoted to a description of the organs of sense and voice, of sleep, and the distinctions of sex. The accurate knowledge which Aristotle exhibits of the anatomy and habits of marine animals, such as the kephalopoda and the larger crustacea, leaves no doubt that he derived it from actual observation. Professor Owen says, respecting the living habits of the kephalopoda, Aristotle is more rich in detail than any other zoological author. What is now spoken of as the hectic otolisation of one or more of the arms of the male kephalopod did not escape Aristotle's eye, and while he speaks of the teeth and that which serves these animals for a tongue, it is plain from the context that he means in the one case the two halves of the parrot-like beak, and in the other the anterior end of the adontophore. Books 5-7 deal with the subject of generation. The eighth book contains a variety of details respecting animals, their food, migrations, hibernation, and diseases, with the influence of climate and locality upon them. The ninth book describes the habits and instincts of animals. The details are interesting, but there is, as usual, very little attempt at classification. Disjointed statements and sudden digressions occur, the subject being treated in the order in which they presented themselves to the author. Such curious statements as the following are met with. The raven is an enemy to the bull and the ass, for it flies round them and strikes their eyes. If a person takes a goat by the beard, all the rest of the herd stand by as if infatuated and look at it. Female stags are captured by the sound of the pipe, and by singing, when two persons go out to capture them, one shows himself and either plays upon a pipe or sings, and the other strikes behind when the first gives him the signal. Swans have the power of song, especially when near the end of their life, for they then fly out to sea, and some persons sailing near the coast of Libya have met many of them in the sea singing a mournful song, and have afterwards seen some of them die. Of all wild animals, the elephant is the most tame and gentle, for many of them are capable of instruction and intelligence, and they have been taught to worship the king. In the work On the Parts of Animals, the author considers not only the phenomena of life exhibited by each species, but also the cause or causes to which these phenomena are attributable. After a general introduction, he proceeds to enumerate the three degrees of composition. Viz one, composition out of what some call the elements, such as air, earth, water, and fire, or out of the elementary forces hot and cold, solid, and fluid, which form the material of all compound substances. Two, composition out of these primary substances of the homogeneous parts of animals, e.g. blood, fat, marrow, brain, flesh, and bone. Three, composition into the heterogeneous parts or organs, these parts he describes in detail, considering those belonging to sanguinius animals first and most fully. These divisions correspond roughly to the threefold study of structure, which we nowadays recognize as chemical, histological, and anatomical. As examples of Aristotle's method of treatment, his descriptions of blood, the brain, the heart, and the lung may be considered. Of the blood, he says, what are called fibres are found in the blood of some animals, but not of all. There are none, for instance, in the blood of deer and of rose, and for this reason the blood of such animals as these never coagulates. Too great an excess of water makes animals timorous. Such animals, on the other hand, as have thick and abundant fibres in their blood, are of a more choleric temperament and liable to bursts of passion. Bulls and boars are choleric, for their blood is exceedingly rich in fibres, and the bulls at any rate coagulates more rapidly than that of any other animal. If these fibres are taken out of the blood, the fluid that remains will no longer coagulate. From these quotations it will be noted that Aristotle attributed the coagulum to the presence of fibres, and in this he anticipated Malpighi's discovery made in the 17th century, his remarks on the proportion of coagulum and serum in different animals, which is enlarged upon in the history of animals, harmonized with modern observations. In another of his works he remarks that the blood in certain diseased conditions will not coagulate. This is known to be the case in cholera, certain fibres, asphyxia, etc., and the fact was probably obtained from Hippocrates. Although Aristotle speaks here of entire absence of coagulation in the blood of the deer and the roe, in the history of animals he admits an imperfect coagulation, for he says so that their blood does not coagulate like that of other animals. The animals named are commonly hunted, and it was probably after they had been hunted to death that he examined them. Now it is generally admitted that coagulation under such circumstances is imperfect and even uncommon. The statement as to the richness in fibres of the blood of bulls and boars has been confirmed by some modern investigations, which have shown that the clot bears a proportion to the strength and ferocity of the animal. The remarks, however, as to the relative rapidity of coagulation, would appear to be contradicted by later observations, for Thakrar came to the conclusion that coagulation commenced sooner in small and weak animals than in strong. Of the brain Aristotle makes the following, among other assertions. Of all the parts of the body there is none so cold as the brain. Of all the fluids of the body it is the one that has the least blood, for in fact it has no blood at all in its proper substance. That it has no continuity with the organs of sense is plain from simple inspection, and still more closely shown by the fact that when it is touched no sensation is produced. The brain tempers the heat and seething of the heart. In order that it may not itself be absolutely without heat, blood vessels from the aorta end in the membrane which surrounds the brain. Of all animals man has the largest brain in proportion to his size and it is larger in men than in women. This is because the region of the heart and of the lung is hotter and richer in blood in man than in any other animal and in men than in women. This again explains why man alone of animals stands erect, for the heat overcoming any opposite inclination makes growth take its own line of direction which is from the centre of the body upwards. Man again has more sutures in his skull than any other animal and the male more than the female. The explanation is to be found in the greater size of the brain, which demands free ventilation proportionate to its bulk. There is no brain in the hind of part of the head. The brain in all animals that have one is placed in the front part of the head because the heart from which sensation proceeds is in the front part of the body. Although it would perhaps be difficult to find anywhere as many errors in as few words, yet it should be observed that Aristotle here shows himself to have been aware of the existence of the membranes of the brain, the Pia-mata and the Dura-mata, and elsewhere he says more explicitly, two membranes enclose the brain. That about the skull is the stronger, the inner membrane is slighter than the outer one. And further it should be noted that he describes the latter membrane as a vascular one. The fact of the brain substance being insensible to mechanical irritation was known to Aristotle and may have been learnt from the practice of Hippocrates. Lastly it should be remembered that though this may have been but a lucky guess on Aristotle's part, the relative weight of brain to the entire body has been shown with few exceptions to be greater in man than in any other animal. In describing the heart, Aristotle says, the heart lies about the centre of the body, but rather in its upper than in its lower half, and also more in front than behind. In man it inclines a little towards the left, so that it may counterbalance the chilliness of that side. It is hollow to serve for the reception of the blood, while its wall is thick that it may serve to protect the source of heat. For here and here alone in all the viscera, and in fact in all the body, there is blood without blood vessels, the blood elsewhere being always contained within vessels. The heart is the first of all the parts of the body to be formed, and no sooner is it formed than it contains blood. For no sooner is the embryo formed than its heart is seen in motion, like a living creature, and this before any of the other parts. The heart is abundantly supplied with sinews. In no animal does the heart contain a bone, certainly in none of those that we ourselves have inspected, with the exception of the horse under a certain kind of ox. In animals of great size the heart has three cavities. In smaller animals it has two, and in all it has at least one. It will be observed that here Aristotle so correctly describes the position of the human heart as to render it probable that he is speaking from actual inspection, although man is not the only animal in which the heart is turned towards the left. In contrasting the heart with the other viscera he appears to have overlooked the existence of the coronary vessels, and to have imagined that the nutrition of the heart was affected directly by the blood in its cavities. Although the heart is not really the first part to appear, the observation of its very early appearance in the embryo, which he treats more fully elsewhere, is alone enough to establish his reputation as an original observer. It is remarkable that Aristotle should have overlooked the presence of the valves of the heart, the structure and functions of which were fully investigated within thirty years of his death by the anatomists of the Alexandrian school. This is the more remarkable as he calls attention here and in the history of animals to the sinews or tendons with which he says the heart is supplied, and by which he probably meant the cordy tendinier. The bone in the heart of which he speaks was probably the cruciform ossification which is normally found in the ox and the stag below the origin of the aorta. It is found in the horse only in advanced age, or under abnormal conditions. The statement that the heart contains no more than three chambers has always been considered as a very gross blunder on the part of Aristotle. Even Cuvier, who generally lavishes upon the philosopher the most extravagant praise, sneers at this. Professor Huxley, however, has shown by a comparison of several passages from the history of animals that what we now call the right oracle was regarded by the aorta as a venous sinus, as being apart not of the heart, but of the great vein, i.e. the superior and the inferior vinycavi. Aristotle speaks of the lung as a single organ, subdivided but having a common outlet, the trachea. Elsewhere he says, canals from the heart pass to the lung and divide in the same fashion as the windpipe does, closely accompanying those from the windpipe through the whole lung. His theory of respiration, as explained in his treatise on the subject, is that it tempers the excessive heat produced in the heart. The lung is compared to a pair of bellows. When the lung is expanded, air rushes in. When it is contracted, the air is expelled. The heat from the heart causes the lung to expand. Cold air rushes in. The heat is reduced, the lung collapses, and the air is expelled. The cold air drawn into the lung reaches the bronchial tubes, and as the vessels containing hot blood run alongside these tubes, the air cools it and carries off its superfluous heat. Some of the air which enters the lungs gets from the bronchial tubes into the blood vessels by transudation, for there is no direct communication between them, and this air penetrating the body rapidly cools the blood throughout the vessels, but Aristotle did not consider the Pneuma which thus reached the interior of the blood vessels to be exactly the same thing as air. It was a subtylised and condensed air, and this we now know to be oxygen. The treatise on the generation of animals is an extraordinary production. No ancient and few modern works equal it in comprehensiveness of detail and profound speculative insight. We find here some of the obscurest problems of biology treated with a mastery which, when we consider the condition of science at that day, is truly astounding. That there are many errors, many deficiencies, and not a little carelessness in the admission of facts, may be readily imagined. Nevertheless, at times the work is frequently on a level with, and occasionally even rises above, the speculations of many advanced embryologists. It commences with the statement that the present work is a sequel to that, on the parts of animals, and first the masculine and feminine principles are defined. The masculine principle is the origin of all motion and generation. The feminine principle is the origin of the material generated. Aristotle's philosophy of nature was teleological, and the imperfect character of his anatomical knowledge often gives him occasion to explain particular phenomena by final causes. Thus animals producing soft-shelled eggs, e.g. cartilaginous fish and vipers, are said to do so because they have so little warmth that the external surface of the egg cannot be dried. Among insects, some, e.g. grasshopper, cricket, ant, etc., produce young in the ordinary way by the union of the sexes. In other cases, e.g. flies and fleas, this union of the sexes results in the production of a scolex, while others have no parents, nor do they have Congress, such as the ephemera, tibula, and the like. Aristotle discusses and rejects the theory that the male reproductive element is derived from every part of the body. He concludes that, instead of saying that it comes from all parts of the body, we should say that it goes to them. It is not the nutrient fluid, but that which is left over, which is secreted, hence the larger animals have fewer young than the smaller, for by them the consumption of nutrient material will be larger, and the secretion less. Another point to be noticed is that the nutrient fluid is universally distributed throughout the body, but each secretion has its separate organ. It is thus intelligible why children resemble their parents, since that which makes all the parts of the body resembles that which is left over as secretion. Thus the hand, or the face, or the whole animal, pre-exists in the sperm, though in an undifferentiated state, and what each of these is in actuality, such is the sperm in potentiality. In later times the two great rival theories put forward to account for the development of the embryo have been, a. the theory of evolution, which makes the embryo pre-existent in the germ, and only rendered visible by the unfolding and expansion of its organs, b. the theory of epigenesis, which makes the embryo arise by a series of successive differentiations from a single homogeneous mass into a complex heterogeneous organism. The above quotation will show how closely Aristotle held to the theory of epigenesis, and in another place he says, not at once is the animal a man or a horse, for the end is last attained, and the specific form is the end of each development. Spontaneous generation is nowadays rejected by science, but Aristotle went so far as to believe that insects, mollusks, and even eels were spontaneously generated. It is however noteworthy in view of modern investigations that he looked upon putrifying matter as the source of such development. A chapter of this work is devoted to the consideration of the hereditary transmission of peculiarities from parent to offspring. The fifth and last book contains inquiries into the cause of variation in the colour of the eyes and hair, the abundance of hair, the sleep of the embryo, sight and hearing, voice and the teeth. Widely different opinions have been held from time to time of the value of Aristotle's biological labours. This philosopher's reputation has perhaps suffered most from those who have praised him most. The praise has often been of such an exaggerated character, as to have become unmeaning, and to have carried with it the impression of insincerity on the part of the writer, such are the laudations of Cuvier, to say as he does, alone in fact, without predecessors, without having borrowed anything from the centuries which had gone before, since they had produced nothing enduring, the disciple of Plato discovered and demonstrated more truths and executed more scientific labours in a life of sixty-two years than twenty centuries after him were able to do, is, of course, to talk nonsense. For the method which Aristotle applied was that which Hippocrates had used so well before him, and it is evident to any one that both his predecessors and contemporaries are frequently laid under contribution by Aristotle, although the authorities rarely, if ever stated by him, unless he is about to refute the view put forward. Exaggerated praise of any author has a tendency to excite depreciation correspondingly unjust and untrue. It has been so in the case of this great man. In the endeavour to depose him from the impossible position to which his panagerists had exalted him, his detractors have gone to any length. The principal charges brought against his biological work have been inaccuracy and hasty generalisation. In support of the charge of inaccuracy some of the extraordinary statements which are met within his works are adduced. These, Professor Huxley says, are not so much to be called errors as stupidities. Some, however, of the inaccuracies alleged against Aristotle are fancied rather than real. Thus he is charged with having represented that the arteries contained nothing but air, that the aorta arose from the right ventricle, that the heart did not heat in any other animal but man, that reptiles had no blood, etc., although in reality he made no one of these assertions. There remain, nevertheless, the gross misstatements referred to above, and which really do occur, such, for instance, as that there is but a single bone in the neck of the lion, that there are more teeth in male than in female animals, that the mouth of the dolphin is placed on the under surface of the body, that the back of the skull is empty, etc., although these absurdities undoubtedly occur in Aristotle's works, it by no means follows that he is responsible for them. Bearing in mind the curious history of the manuscripts of his treatises, we shall find it far more reasonable to conclude that such errors crept in during the process of correction and restoration by men apparently ignorant of biology, than that, to take only one case, an observer who had distinguished the cetacea from fishes and had detected the hidden mammae, discovered their lungs, and recognised the distinct character of their bones should have been so blind as to fancy that the mouth of these animals was on the under surface of the body. That Aristotle made hasty generalisations is true, but it was unavoidable. Biology was in so early a stage that a theory had often of necessity to be founded on a very slight basis of facts. Yet notwithstanding this drawback so great was the sagacity of this philosopher that many of his generalisations, which he himself probably looked upon as temporary, have held their ground for twenty centuries, or having been lost sight of, have been discovered and put forward as original by modern biologists. Thus the advantage of physiological division of labour was first set forth, says Milner Edwards, by myself in 1827, and yet Aristotle had said that, whenever nature is able to provide two separate instruments for two separate uses, without the one hampering the other, she does so, instead of acting like a coppersmith, who for cheapness makes a spit and a candlestick in one. It is only when this is impossible that she uses one organ for several functions. In conclusion we may say that the great Staggerite expounded the true principles of science, and that when he failed his failure was caused by lack of materials. His desire for completeness perhaps attempted him at times to fill in gaps with such makeshifts as came to his hand, but no one knew better than he did, that theories must be abandoned unless their teachings tally with the undisputable results of observation. Fathers of Biology by Charles McCree Chapter 3 St. Galen Under the Ptolemyse a powerful stimulus was given to biological studies at Alexandria. Scientific knowledge was carried a step or two beyond the limit reached by Aristotle. Thus Erassistratus and Herobphilus thoroughly investigated the structure and functions of the valves of the heart, and were the first to recognize the nerves as organs of sensation. But, unfortunately, no complete record of the interesting work carried on by these men has come down to our times. The first writer after Aristotle, whose works arrest attention, Ischius Plinius Secondus, whose so-called natural history in 37 volumes, remains to the present day as a monument of industrious compilation. But as a biologist properly so called, Plinius is absolutely without rank, for he lacked the practical acquaintance with the subject, which alone could enable him to speak with authority. Of information he had an almost inexhaustible store of actual knowledge, the result of observation and experience, so far as biological studies were concerned. He had but little. This was largely due to the encyclopedic character of the work he undertook. His mental powers were weighed down by an enormous mass of unarranged and ill-digested materials. But it was also due to the peculiar bent of Plinius' mind. He was not, like Aristotle, an original thinker. He was essentially a student of books and immensely industrious, but not always judicious compiler. Often his selections from other works prove that he failed to appreciate the relative importance of the different subjects to which he made reference. His knowledge of the Greek language appears, too, to have been defective, for he gives at times the wrong Latin names to objects described by his Greek authorities. To these defects must be added, his marvellous readiness to believe any statement provided only that it was uncommon. While, on the other hand, he showed an indefensible skepticism in regard to what was really deserving of attention. The chief value of his work consists in the historical and chronological notes of the progress of some of the subjects of which he treats. Fragments of writings which would otherwise be lost to us. Plini was killed in the destruction of Pompeii and the Dominus 79. Claudius Galenos was born at Pergamus in Asia Minor in the 131st year of the Christian era. Few writers ever exercised for so long a time such an undisputed sway over the opinions of mankind as did this wonderful man. His authority was estimated at a much higher rate than that of all the biological writers combined, who flourished during a period of more than 12 centuries and it was often considered a sufficient argument against a hypothesis or even an alleged matter or fact that it was contrary to Galen. Endowed by nature with a penetrating genius and a mind of restless energy, he was eminently qualified to profit by a comprehensive and liberal education, and such he received. His father, Nikon, an architect, was a man of learning and ability, a distinguished mathematician and an astronomer, and seems to have devoted much time and care to the education of his son. The use appears to have studied philosophy successively in the schools of the Stoics, academics, peripathetics, and Epicureans, without attaching himself exclusively to any one of these, and to have taken from each what he saw to be the most essential parts of their system, rejecting, however, altogether the tenets of the Epicureans. At the age of twenty-one, on the death of his father, he went to Smirna to continue the study of medicine, to which he had now devoted himself. After leaving this place and having traveled extensively, he took up his residence at Alexandria, which was then the most favorable spot for the pursuit of medical studies. Here he is said to have remained until he was twenty-eight years of age, when his reputation secured his appointment in his native city of Pergamus, to the office of physician in charge of the athletes in the Gymnasia, situated within the precincts of the Temple of Iscolopius. For five or six years he lived in Pergamus, and then a revolt compelled him to leave his native town. The advantages offered by Rome led him to remove Zither and take up his residence in the capital of the world. Here his skill, sagacity, and knowledge soon brought him into notice and excited the jealousy of the Roman doctors, which was still further increased by some wonderful cures the young Greek physician succeeded in affecting. Possibly it was owing to the ill feeling shown to Galen that, on the outbreak of an epidemic, a year afterwards, he left the imperial city and proceeded to Brindisi and embarked for Greece. It was his intention to devote his time to the study of natural history, and for this purpose he visited Cyprus, Palestine, and Lemnos. While at the last named place, however, he was suddenly summoned to Aquileia to meet the emperors Marcus Aurelius and Lucius Verus. He travelled through Thrace and Macedonia on food, met the imperial personages, and prepared for them a medicine, for which he seems to have been famous, and which is spoken of as the Theriac. It was probably some combination of opium with various aromatics and stimulants, for underdotes of many different kinds were habitually taken by the Romans to preserve them from the ill effects of poison and the bites of the venomous animals. With the emperor Marcus Aurelius he returned to Rome and became afterwards doctor to the young emperor Commodus. He did not, however, remain for a long period at Rome, and probably passed the greater part of the rest of his life in his native country. Although the date of his death is not positively known, yet it appears from a passage in his writings that he was living in the reign of Septimus Severus, and Suidas seems to have reason for asserting that he reached his 70th year. Galen's writing represents the common depository of the anatomical knowledge of the day, what he had learned from many teachers, rather than the results of his own personal research. Roughly speaking, they deal with the following subjects, anatomy and physiology, dietics and hygiene, pathology, diagnosis and semiology, pharmacy and materica medica, therapeutics. The only works of this voluminous writer at which we can hear glance are those dealing with anatomy and physiology. These exhibit numerous illustrations of Galen's familiarity with practical anatomy, although it was most likely comparative rather than human anatomy, at which he especially worked. Indeed, he seems to have had but a few opportunities of carrying on human dissections, for he thinks himself happy in having been able to examine at Alexandria two human skeletons, and he recommends the dissection of monkeys because of their exact resemblance to man. To this disadvantage may, perhaps, be attributed the readiness which sometimes appears to assume identity of organization between man and the brutes. Thus, because in certain animals he found a double biliary duct, Hink concluded the same to be the case in man. And in one instance he proceeded to deduce the cause of disease from this erroneous assumption. He supposed that there were three modes of existence in man, namely, a, the nutrition, which was common to all animals and plants, of which the liver was the source, b, the vital, of which the heart was the source, c, the rational, of which the brain was the source. Again he considered that the animal economy possesses four natural powers, one, the attractive, two, the alternative or assimilative, three, the retentive or digestive, four, the expulsive. Like his predecessors, he asserted that there were four humours, namely, blood, yellow bile, black bile, and aqueous serum. He held that it was the office of the liver to complete the process of sanguification commenced in the stomach, and that during this process the yellow bile was attracted by the branches of the hepatic duct and gallbladder, the black bile being attracted by the spleen, and the aqueous humour by the two kidneys, while the liver itself retained the pure blood, which was afterwards attracted by the heart, through the venakava, by whose ramifications it was distributed to the various parts of the body. Following Aristotle especially, he regarded hair, nails, arteries, veins, cartilage, bone, ligament, membranes, glands, fat and muscle as the simplest constituents of the body, formed immediately from the blood, and perfectly homogeneous in character. The organic members, lungs, liver, etc. he looked upon as formed of several of the foregoing simple parts. The osteology contained in gallant's works is nearly as perfect as that of the present day. He correctly names and describes the bones and sutures of the cranium, notices the quadrilateral related shape of the perietals, the peculiar situation and shape of the spinoid, and the form and character of the etymoid, molar, maxillary and nasal bones. He divides the vertebral columns into cervical, dorsal and lumbar portions. With regard to the nervous system, he thought that the nerves of the senses are distinct from those which impart the power of motion to muscles, that the former are derived from the anterior parts of the brain, while the latter arise from the posterior portion, or from the spinal cord. He maintains that the nerves of the finer senses are formed of matter too soft to be the vehicles of muscular motion. Various on the other hand, the nerves of motion are too hard to be susceptible of fine sensibility. His description of the method of demonstrating the different parts of the brain, by dissection, is very interesting, unlike his references to various instruments and contravences, proves him to have been a practical and experienced anatomist. In his description of the organs and process of nutrition, absorption by the veins of the stomach is correctly noticed, and the union of the mesentery veins into one common venoportae is pointed out. The communications between the ramifications of the venoportae and of the proper veins of the liver are supposed by Galen to be affected by means of unostomosing pores or channels. Although it is evident that Galen was ignorant of the true absorbent system, yet he appears to have been aware of the lacteals. For he says that in addition to those mesentery veins, which by their union form the venoportae, there are visible in every part of the mesentery other veins, proceeding also from the intestines, which terminate in glands, and he supposes that these veins are intended for the nourishment of the intestines themselves. Some of Galen's contemporaries asserted that upon exposing the mesentery of a sucking animal, several small vessels were seen filled, first with air, and afterwards with milk. They had doubtless mistaken colorless lymph for air, but Galen ridicules both assertions, and thereby shows that he had not examined the contents of the lacteals. This is somewhat remarkable, because as a rule he omitted no opportunity of determining with certainty by vivisection and experiments on living animals, the uses of the various parts of the body. As an illustration of this, we have his correct statement, established by experiment, that the pylorus acts as a valve only during the process of digestion, and that it is relaxed when digestion is completed. He recognizes that the flesh of the heart is somewhat different to that of the muscles of voluntary motion. Its fibers are described as being arranged in longitudinal and transverse bundles. The former bars their contractions shortening the organ, the latter compressing and narrowing it. Such statements show that he regarded the heart as essentially muscular. He thought, however, that it was entirely destitute of nerves. Although he admitted that possibly it had one small branch derived from the nervous vagus sent to it, yet he entirely overlooked the great nervous plexus surrounding the roots of the blood vessels, from which branches proceed in company with the branches of the coronary arteries and veins, and penetrated the muscular substance of the ventricles. He endeavored to prove by experiment, observation and reasoning, that the arteries as well as the veins contained blood, and in this connection he tells an amusing story. A certain teacher of anatomy who had declared that the aorta contained no blood, was earnestly desired by his pupils, who were ardent disciples of Galen, to exhibit the requisite demonstration by themselves offering animals for the experiment. He, however, after various subterfuges declined, until they promised to give him a suitable remuneration, which they raised by subscription among themselves, to the amount of a thousand drachma, perhaps about thirty pounds. The professor, being thus compelled to commence the experiment, totally failed in his attempt to cut down upon the aorta to the no small amusement of his pupils, who thereupon, taking up the experiment themselves, made an opening into the thorax, in the way in which they had been instructed by Galen, passed one ligature around the aorta, at the part where it attaches itself to the spine, and another at its origin, and then, by opening the intervening portion of the artery, showed that blood was contained in it. The arteries Galen thought possessed a positive and attractive power of their own, independently of the heart, the moment of their dilatation, being the moment of their activity. They, in fact, drew their charge from the heart, as the heart by its diastole drew its charge from the venakava and the pulmonary vein. The pulse of the arteries he also thought was propagated by their codes, not by the wave of blood thrown into them by the heart. He thought that at every systole of the arteries a certain portion of their contents was discharged at their extremities, namely by the excellence and secretory vessels. So he demonstrated the anastomosis of arteries and veins. He nowhere hints his belief that the contents of the former pass into the letter, to be conveyed back to the heart, and from it to be again diffused over the body. He made a near approach to the Harveyian theory of the circulation, as Harvey himself admits in his Demoto Cordes. But the grand point of difference between Galen and Harvey is the question whether or not, at every systole of the left ventricle, more blood is thrown out than is expended on exhalation, secretion and nutrition. Upon this point Galen held the negative, and Harvey as we all know the affirmative. The famous Asclepians held that respiration was for the generation of the soul itself, breath and life being thus considered to be identical. Hippocrates thought it was for the nutrition and refrigeration of the inner heat, ours total for its ventilation, eras the stratus for the filling of the arteries with spirits. All these opinions are discussed and commented upon by Galen, who determines the purpose of respiration to be, one, to preserve the animal heat, two, to evacuate from the blood the products of combustion. He conjectured that there was an atmospheric air, not only a quality friendly to the vital spirit, but also a quality inimical to it, which conjecture he threw from observation of the various phenomena accompanying the support and the extinction of flame, and he says that if we could find out why flame is extinguished by absence of the air, we might then know the nature of that substance which imparts warmth to the blood during the process of respiration. On another occasion he says that it is evidently the quality and not the quantity of the air which is necessary to life. He further shows that he recognized the analogy between respiration and combustion by comparing the lungs to a lamp, the heart to its wick, the blood to the oil, and the animal heat to the flame. From certain observations in various parts of his works it appears that, although ignorant of the doctrine of atmospheric pressure, he was acquainted with some of its practical effects. Thus he says, if you put one end of an open tube under water, and suck out the air with the other end, you will draw up water into the mouth, and that it is in this way that infants extract the milk from the mother's breast. Again Erassistratos supposed that the vapor of carcol and of certain pits and wells was fed out to life because lighter than common air, but Galen maintained it to be heavier. He describes two kinds of respiration, one by the mouth of the arteries of the lungs, and one by the mouth of the arteries of the skin. In each case he says, the surrounding air is drawn into the vessels during their diastole. For the purpose of cooling the blood, and during their systole the folliginous practicals derived from the blood and other fluids of the body are forced out. He considers the diaphragm to be the principal muscle of respiration, but he makes a clear distinction between ordinary respiration, which he calls a natural and involuntarily effort, and that deliberate and forced respiration, which is obedient to the will. And he says that there are different muscles for the two purposes. Elsewhere he particularly points out the two sets of intercostal muscles and their mode of action, of which before his time he asserts that anatomists were ignorant. He describes various effects produced on respiration and on the voice by the division of those nerves which are connected with the thorax, and shows particularly the effect of dividing the recurrent branch of his sixth pair of cerebral nerves, the pneumogastric of modern anatomy. He explains how it happens that after division of the spinal cord provided that division be beneath the lower termination of the neck, the diaphragm will still continue to act, in consequence, namely, of the origin of the phrenic nerve being above the lower termination of the neck. Before the time of Galen the medical profession was divided into several sects, dogmaticae, empiricae, eclecticae, pnoymaticae, and episyntheticae, who were always disputing with one another. After his time all sects seem to have merged in his followers. The subsequent Greek and Roman biological writers were mere compilers from his works, and as soon as his writings were translated into Arabic they were at once adopted throughout the East to the exclusion of all others. He remained paramount throughout the civilized world until within the last three hundred years. In the records of the College of Physicians of England we read that Dr. Joines was cited before the College in 1559 for impugning the infallibility of Galen and was only admitted again into the privileges of his fellowship on acknowledgement of his error and humble recantation signed with his own hand. Kurt Sprengel has well said that if the physicians who remained so facefully attached to Galen's system had inherited his penetrating mind, his observing glance, and his depth, the art of healing would have approached the limit of perfection before all the other sciences. But it was written in the Book of Destiny that mind and reason were to bend under the yoke of superstition and barbarism, and were only to emerge after centuries of lethargic sleep. End of Section 3 Section 4 of Fathers of Biology. This is a LibriVox recording. All LibriVox recordings are in the public domain. For more information or to volunteer please visit LibriVox.org recording by Anna Simon. Fathers of Biology by Charles McRae. Chapter 4. Vizavius. The authority of Galen at once a despotism and a religion was scarcely ever called in question until the 16th century. No attempt worth recording was made during 1300 years to extend the boundary of scientific knowledge in anatomy and physiology. It is true that this scholastic philosopher, Albertus Magnus, who was for a short time, 1260-1262, Bishop of Radespont, in the middle of the 13th century, wrote a history of animals, which was a remarkable production for the age in which he lived. Although Sir Thomas Brown, in his famous inquiries into common errors, speaks of these tractates as requiring to be received with caution, adding, as regards Albertus, that he was a man who much advanced these opinions by the authority of his name and delivered most conceits with strict inquiry into few. As regards human anatomy it was considered, during the Middle Ages, to be impiety to touch with the scalpel the dead image of God as man's body was called. Mundanus, the professor of medicine at Bologna from 1315-1318, was the first to attempt any such thing. He exhibited the public dissection of three bodies, but by this created so great a scandal that he gave up the practice and contented himself with publishing a work, De Anatomy, which formed a sort of commentary on Galen. This work, with additions, continued to be the textbook of the schools until the time of Fasilius, who founded the study of anatomy as nowadays pursued. Andreas Fasilius was born at Brussels on the last day of the year 1514 of a family which for several generations had been eminent for medical attainments. He was sent as a boy to Levin, where he spent the greater part of his leisure in researches into the mechanism of the lower animals. He was a born deceptor, who, after careful examination in his early days of rats, moles, dogs, cats, monkeys and the like, came in afterlife to be dissatisfied with any less knowledge of the anatomy of man. He acquired great proficiency in the scholarship of the day. Indeed, the Latin in which he afterwards wrote his great work is so singularly pure that one of his detractors pretended that Fasilius must have got some good scholar to write the Latin for him. Latin was not the only language in which he was proficient. He added Greek and Arabic to his other accomplishments, and this for the purpose of reading the great biological works in the languages in which they were originally written. From Levin the youth went to Paris, where he studied anatomy under a most distinguished physician, Silvius. It was the practice of that illustrious professor to read to his class Galen on the use of parts, omitting near the older sections where exact knowledge of an atomical detail was necessary. Sometimes an attempt was made to illustrate the lecture by the dissection of a dog, but such illustration more often exposed the professor's ignorance than it added to the student's knowledge. Indirectly, however, it did good, for whenever Silvius, after having tried in vain to demonstrate some muscle or nerve or vain, left the room, his pupil Fasilius slipped down to the table, dissected out the part with great neatness, and triumphantly called the professor's attention to it on his return. Besides studying under Silvius, Fasilius had for his teacher at Paris the famous winter of Andernach, who was physician to Francis I. This learned man, in a work published three years after this period, speaks of Fasilius as a youth of great promise. At the age of nineteen, Fasilius returned to Levin, and here for the first time he openly demonstrated from the human subject. In this connection a somewhat ghastly story is told, which serves to show the intensity of the enthusiasm with which our anatomist was inspired. On a certain evening a chance that Fasilius, in company with a friend, had rambled out of the gates of Levin to a spot where the bodies of executed criminals were want to be exposed. A noted robber had been executed, his body had been chained to a stake and slowly roasted, and the birds had so entirely stripped the bones of every vestige of flesh that a perfect skeleton, complete and clean, was suspended before the eyes of the anatomist, who had been striving hitherto to piece together such a thing out of the bones of many people, guarded as occasion offered. Mounting upon the shoulder of his friend, Fasilius ascended the charred stake and forcibly tore away the limbs, leaving only the trunk which was securely bound by iron chains. With these stolen bones under their clothes the two youths returned to Levin. In the night, however, and alone the sturdy Fasilius found his way again to the place, which the most men, at any rate in those times, would have been associated with unspeakable horrors, and there by sheer force wrenched away the trunk and buried it. Then, leisurely and carefully, day after day, he smuggled through the city gates bone after bone. Afterwards, when he had set up the perfect skeleton in his own house, he did not hesitate to demonstrate from it, but such an act of daring plunder could not escape detection, and he was banished from Levin for the offence. This story is here quoted only to show the extraordinary physical and moral courage which the anatomist possessed, which upheld him through toils, dangers and disgusts, by which he was strengthened to carry on, even in a cruel and superstitious age and placed, as he was, on the very threshold of the Inquisition, a work at all times repulsive to flesh and blood. After serving for a short time as a surgeon in the Army of the Emperor Charles V, Fasilius went to Italy, where he at once attracted the attention of the most learned men, and became, at the age of twenty-two, Professor of Anatomy at the University of Parva. This was the first purely anatomical professorship that had been established out of the funds of any university. For seven years he held the office, and he was at the same time Professor at Bologna and at Pisa. During these years his lectures were always well attended, for they were a striking innovation on the tameness of conventional routine. In each university the services of the Professor were confined to a short course of demonstrations, so that his duties were complete when he had spent, during the winter, a few weeks at each of the three towns in succession. He then returned to Venice, which he appears to have made his headquarters. At this city, as well as at Pisa, special facilities were offered to the Professor for obtaining bodies either of condemned criminals or others. At Padua and Bologna, the enthusiasm of the students, who became resurrectionists on their teachers' behalf, kept the lecture-table supplied with specimens. They were in the habit of watching all the symptoms in men dying of a fatal melody, and noting where, after death, such men were buried. The seclusion of the graveyard was then invaded, and the corpse secretly conveyed by Andeos to his chamber, and concealed sometimes in his own bed. A diligent search was at once made to determine accurately the cause of death. This pitiless zeal for correct details in anatomy, associated as it was with indefatigable practice in physics, appeared to Fraselius, as it does to his successors of today, to be the only satisfactory method of inquiring that knowledge which is essential to a doctor. Thus it was that he, who at the age of twenty-two was able to name, with his eyes blindfolded, any human bone put into his hand, who was deeply versed in comparative anatomy, and had more accurate knowledge of the human frame than any greybeard at the time, enjoyed afterwards a reputation as a physician which was unbounded. One illustration of his sagacity in diagnosis will suffice. A patient of two famous court physicians at Madrid had a big and wonderful tumor on the loins. It would have been easily recognized in these days as an aneurysmal tumor, but it greatly puzzled the two doctors. Fraselius was therefore consulted and said, There is a blood vessel dilated. That tumor is full of blood. They were surprised at such a strange opinion. But the man died, the tumor was opened, the lot was actually found in it, and we are told, in admirationm raptifuere omnes. It was not until after Fraselius had been three years professor that he began to distrust the infallibility of Galen's anatomical teaching. Constant practical experience and dissection, both human and comparative, slowly convinced him that great anatomist as a divus homo had undoubtedly been. His statements were not only incomplete, but often wrong. Further, that Galen very rarely wrote from actual inspection of the human subject, but based his teaching on a belief that the structure of a monkey was exactly similar to that of a man. With this conviction established, Fraselius proceeded to note with great care all the discrepancies between the text of Galen and the actual parts which it endeavoured to describe, and in this way a volume of considerable thickness was soon formed, consisting entirely of annotations upon Galen. That generally received authorities being thus found to be unreliable, it became necessary in the next place to collect and arrange the fundamental facts of anatomy upon a new and sounder basis. To this task Fraselius at the age of 25 devoted himself and began his famous work on the fabric of the human body. Owing possibly to the good fortune of his family and to the income which he derived from his professorships, Andreas was able to secure for his work the aid of some of the best artists of the day. To Jean Calcaire, one of the ablest of the pupils of Titian, are due the splendid anatomical plates which illustrate the corporese humani fabrica, and which are incomparably better than those of any work which preceded it. To him most likely is due also the woodcut which adorns the first page, and which represents the young Fraselius wearing professors' robes standing at a lecture table and pointing out from a robust subject that lies before him the inner secrets of the human body, while the tears of benches that surround the professor are completely crowded with grave doctors struggling to see, even climbing upon the railings to do so. But throughout the work the plates are used simply to illustrate and elucidate the text and the information furnished in a letter is minute and accurate and stated in well-polished Latin. As the author proceeds he finds it necessary to disagree with Galen and the reasons for this disagreement are given. The inevitable result follows that Fraselius is placed at issue not only with the divine man, but also with all those who for thirteen centuries had unquestioningly followed him. Such a result Fraselius must have foreseen. It was not therefore a great surprise to him perhaps to receive, soon after the publication of his work, a violent onslaught from his old master Silvius. He simply replied to it by a letter full of respect and friendly feeling, inquiring wherein he had been guilty of error. The answer he got was that he must show proper respect for Galen if he wished to be regarded as a friend of Silvius. In 1546, three years after the publication of his great work, Andeus was summoned to Ratisbon to exercise his skill upon the emperor, and from that date he was ranked among the court physicians. In the same year, 1546, in a long letter entitled Deusurradicus Cine, he not only treats of the medicine by which the emperor's health had been restored, but he vindicates his teaching against his assailants and again gives cumulative proof of the fact that Galen had dissected only brutes. It was the practice of Fraselius, while he was professor in Italy, to issue a public notice the day before each demonstration, stating the time at which it would take place and inviting all who decried his errors to attend and make their own dissections from his subject and confound him openly. It does not appear that anyone was rash enough ever to accept the challenge, yet although the majority of the young men were on the side of Fraselius, the older teachers continued to regard him as a heretic, and in 1551 Silvius published a bitterly personal attack. It was nothing to him that the results of actual dissection were against him. He even went so far as to assert that the men of his time were constructed somewhat differently to those of the time of Galen. Thus, to the proof that Fraselius gave that the carpal bones were not absolutely without marrow as Galen had asserted, Silvius replied that the bones were harder and more solid among the ancients, and were in consequence destitute of medallary substance. Again, when Fraselius showed that Galen was wrong in describing the human femur and humerus as greatly curved, Silvius explained the discrepancy by saying that the wearing of narrow garments by the moderns had straightened the limbs. Through these attacks, however, the writings of Fraselius fell into somewhat bad odor in the court, for in that very superstitious age there was a kind of vague dread felt of reading the works of a man against whom such serious charges of arrogance and impiety were brought, and so it came about that when he received the summons to take up his residence permanently at Madrid, and the orthodoxy of the day seemed for the moment to triumph. In a fit of proud indignation he burned all his manuscripts, destroying a huge volume of annotations upon Galen, a whole book of medical formulae, many original notes on drugs, the copy of Galen from which he elected and which was covered with marginal notes of new observations that had occurred to him while demonstrating, and the paraphrases of the books of Rassus, in which the knowledge of the Arabian was collated with that of the Greeks and others. The produce of the labour of many years was thus reduced to ashes in a short fit of passion, and from this time Fraselius lived no more from controversy or study. He gave himself up to pleasure in the pursuit of wealth, resting on his reputation and degenerating into a mere torture. As a partitioner he was held in high esteem. When the life of Don Carlos, Philip's son, was despaired of, it was Fraselius who was called in, and who, seeing that the surgeons had bound up the wound in the head so tightly that an abscess had formed, promptly brought relief to the patient by cutting into the perichranium. The cure of the prince, however, was attributed by the court to the intercession of San Diego, and it is possible that on the subject of this alleged miraculous recovery Fraselius may have expressed his opinion rather more strongly than it was safe for a Netherlander to do. At any rate the priests always looked upon him with dislike and suspicion, and at length they and the other enemies of the great anatomist had their revenge. A young Spanish nobleman had died, and Fraselius who had attended him obtained permission to a certain, if possible, by a post-mortem examination the cause of death. On opening the body the heart was set by the bystanders to beat, and the charge, not merely of murder, but of impiety also, was brought against Fraselius. It was hoped by his persecutors that the letter charge would be brought before the inquisition, and result in more rigorous punishment than any that will be inflicted by the judges of the common law. The king of Spain, however, interfered and saved him on condition that he should make a pilgrimage to the Holy Land. Accordingly he set out from Madrid for Venice and thence to Cyprus, from which place he went on to Jerusalem, and was returning not to Madrid, but to Padua, where the professorship of physics had been offered him, when he suffered shipwreck on the island of Zante, and there perished miserably of hunger and grief on October 15, 1564, before he had reached the age of fifty. His body was found by a travelling goldsmith, who recognised, notwithstanding their starved outlines, the features of the renowned anatomist, and respectfully buried his remains, and raised a statue to his memory. Two of the works of this great man have been already referred to, namely Besides these the following have appeared Apolgie Francischi Putti Progaleno in Anatomy, a great work on surgery in seven books. With respect to the last of these it may be sufficient to remark that there is every reason to believe that the name of the famous anatomist was stolen after his death to give value to the production, which was compiled and published by a Venetian named Bogarucci, and that Veselius is not responsible for the contents. The other works are undoubtedly genuine. In 1562 Andreas seems to have been roused for a short time from the lethargy into which he had sunk by an attack from Francischi Puttius, for to this attack a reply appeared from a writer calling himself Gabriel Cunius, which has always been attributed by the most competent authorities to Veselius himself. In this rather long work, covering as it does more than fifty pages in the folio edition, the views of Veselius, which are at variants with Galen, are gone through seriatim and defended. In 1561 Philopius, who had studied under Veselius, published his anatomical observations containing several points in which he had extended the knowledge of anatomy beyond the limits reached by his master. He had taught publicly for thirteen years at Ferrara and had presided for eight years over an anatomical school so that he was no novice in the field of biology. Yet so completely had Veselius lost the philosophic temperament that he regarded this publication as an infringement of his rights, and in this spirit wrote an Examen Observationum Fallope, in which he decried the friend who had made improvements on himself as he had been decried for his improvements on Galen. The manuscript of this work, finished at the end of December 1561, was committed by the author to the care of Paulus Tupulus of Venice, orator to the king of Spain, who was to give it to Philopius. The orator, however, did not reach Padua until after the death of Philopius, and he consequently retained the document until Veselius, on his way to Jerusalem, took possession of it, and caused it to be published without delay. It appeared at Venice in 1564. The letter on the China route, a plant we know nowadays as Sars-Parele, by the use of which the emperor's recovery was affected, has been already referred to. It was addressed to the anatomist's friend Joachim Roulans. Very little space, however, is taken up with a description of the medicine which gives title to the letter. Something certainly is said of the history and nature of the plant, the preparation of the decoction, and its effects, but the writer soon introduces the subject, which was at that time of very vital importance to him, namely, his position with regard to the statements of Galen and his followers. He collects together various assertions of the Greek anatomist, on the bones, the muscles, and ligaments, the relations of veins and arteries, the nerves, the character of the peritoneum, the organs of the thorax, the skull, and its contents, etc., and shows from each and all of these that reference had not been made to a human subject, and that therefore the statements were unreliable. To the work on the fabric of the human body we have already alluded, as well as to the causes which led to its being written. More than half of this great treatise is occupied with a minute description of the build of the human body, its bones, cartilages, ligaments, and muscles. It may have been owing to the thorough acquaintance which Veselius showed with these parts that his detractors pretended afterwards that he only understood superficial injuries. But other branches of anatomy are fully dealt with. The veins and arteries are described in the third book, and the nerves in the fourth. The organs of nutrition and reproduction are treated of in the next, while the remaining two books are devoted to descriptions of the heart and brain. Veselius gives a good account of the swenoid bone, with its large and small wings and its pteragoid processes, and he accurately describes the vestibule in the interior of the temporal bone. He shows the sternum to consist, in the adult, of three parts, and the sacrum of five or six. He discovered the valve which guards the foramen ovale in the fetus, and he not only verified the observation of a chin as to the valve-like fold guarding the entrance of each hepatic vein into the inferior vena cava, but he also fully described the vena asijus. He observed, too, the canal which passes in the fetus between the umbilical vein and vena cava, and which has since been known as adductus venosis. He was the first to study and describe the mediostinum, correcting the error of the ancients, who believed that this duplicature of the pleura contained a portion of the lungs. He described the omentum and its connections with the stomach, the spleen, and the colon, and he enunciated the first correct views of the structure of the pleurus, noticing at the same time the small size of the sequel appendix in man. His account of the anatomy of the brain is fuller than that of any of his predecessors, but it does not appear to have well understood the inferior recesses, and its description of the nerves is confused by regarding the optic as the first pair, the third as the fifth, and the fifth as the seventh. The ancients believed the optic nerve to be hollow for the conveyance of the visual spirit, but Fezzelius showed that no such tube existed. He observed the elevation and depression of the brain during respiration, but being ignorant of the circulation of the blood, he wrongly explained the phenomenon. Exclusively an anatomist, he makes but brief references in his great work to the functions of the organs which he describes. Where he differs from Galen on these matters, he does so apologetically. He follows him in regarding the heart as the seed of the emotions and passions, the hottest of all the viscera and soles of heat of the whole body, although he does not, as Aristotle did, look upon the heart as giving rise to the nerves. He considers the heart to be in ceaseless motion, alternately dilating and contracting, but the dryesterly is in his opinion the influential act of the organ. He knows that aminances or projections are present in the veins, and indeed speaks of them as being analogous to the valves of the heart, but he denies to them the office of valves. To him the motion of the blood was of a two-and-fro kind, and valves in the veins acting as such would have interfered with anything of the sort. He expresses clearly the idea that was entertained in the old physiology of the attractions exerted by the various parts of the body for the blood, and especially that of the veins and heart for the blood itself. The right sign is of the heart, he says, attracts blood from the vena cava, and the left attracts air from the lungs through the arteria venalis, pulmonary vein, the blood itself being attracted by the veins in general, the vital spirit by the arteries. Again he speaks of the blood filtering through the septum between the ventricles as if through a sieve, although he knows perfectly well from his dissection that the septum is quite impervious. It will thus be seen that the physiological teaching of Kaelin was left undisturbed by Veselius.