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Les diagrammes suivants illustrant la m^thode. 1 2 3 1 2 3 4 5 6 MICROCOPY RESOLUTION TEST CHART ANSI and ISO TEST CHART No 2i 1.0 I.I 1^ |[Z2 2.0 1.8 1.25 1.4 1.6 _^ .APPLIED irvVlGE Inc —^ '663 tast Mqir Street r.^ Rochesle'. Ne* Tork '4609 uS* ■= (716) *ej - OJOO - Phone = (716) 288- M89 - Fo. PATHFINDERS OF PHYSIOLOGY - BY— J. H. ui:\ipsti-:r, A. u., m. d. IDITOre OF TMI DETBOIT MIDICAL JOUHNAL FOHMIRLV LlCTURI* IN PHysiOLOGV OITROIT COULIOE OF MEDlCINl MIMBtR OF THE OETrtOIT MEUICAL CLU8 WAYNE COUNTY MEDICAL •OniTY MICMISAN STATE AND AMERICAN MEDICAL ASSOCIATIONS Mience * * * I taught them how the stars do rise And set in mystery, and devised for them Aiimher, the inducer of philosophy, The synthesis of letters, and besides The artificer of all things. Memory That sweet Muse-Mother. " ■•■Aeschylus PUBLISHED BY THE THE PETROIT MEDICAL JUUK.NAL COMPAXY '914 Published by The Detroit Medical Journal Company 1914 FOREWORD Tho following pajrcs aro the result of the writ. I's iniiultrcnct" in biography as a recreation. Tiic title Pathfinders is presumed t reman,..,! in a .,uie,scent ^tate. The rise and iail of sysL^ms and methods would dispose one to w.mder if the end is yet; if we have at last reached the be.lrock of fad in a eientilic .sense. The Kreat a.lvantaRe ol truth over error is Il,;it tliouRh at times crushed to earth, It will ri.se atfain. Not until science and plulosophv had freed them selves from the throe, of ecdesiasticism. was any marked forward movement possible, for. durinvr the lir.^t fifteen centuries of the Chri.s- tiaii era the most preposterous ideas of plivsioloffv obtainet ,nn,eives the idea of experimenting on St, Martin • :;. 1— Beaumont Honored by the Mlchi.sran Med'cal Society (28)— Seeks Assistance of two Leading Scientists (29)— St. Martin Attains Fame ThvonKh His Sto--b , yM '. ^B^^.^jnont resign:^ from ::..: a. a,, rw,-^ His Death ( ;i I l -His Work (HLM. CHAPTER IV. Glycogenic Function of the Liver — Vaso Motor Nerves — Claude Bernard Boriiards Early Life and flducation (35) — His Productive Period (36) — Work on Gastric Digestion (37)— Glycogenic Function of the Liver (37) — Vaso-Motor Nerves (39) — The Action of Carbon Monoxide Gaa (39) A Friond of Pasteur (40) — Domestic Troubles (40) — Made One of the "Im- mortals" (40) — His Dexterity as Experimenter (41) — Death In 1878, State Funeral (41). CHAPTER V. Respiration 42 Views of the Ancients on Respiration (42 )— Mechanics of Respiration (42) —Boyle and His Work (43)— Robert Hooke (43)— Mayow and His Re- searches (44) — Respiration Prior to the Eighteenth Century (45) The Eighteenth Century School (46)— Priestly and His Dephlogisticated Air (47)— Priestly and Benjamin Franklin (48)— Priestly Comes to America (48) — The Phlogiston Theory (49)— Lavoisier and His Work (49)— The First to Uee the Word Oxygen (49). CHAPTER VI. The Nervous System .50 The Heart the Seat of the Soul thought the Ancient Hebrews (50) The Alexandrian School (50) — Galen Piodaimed the "Brain to be the Seat of Thought and Sensation" (51)— Thomas Willis (51)— Frances Glisson Dis- covers Irritability of Muscle (52)— Goll and Phrenology (52)— Bell and Magendle (63)— Broca and the "Speech Center" (54)— Pathologic States of the Brain and Nervous System (55) — Tuke, Benjamin Rush, and Pinel (55). CHAPTER VII. The CeU Theory 5g Anticipated in the Seventeenth Century (56)— Bichat and His Contribu- tion to the Theory (56)— The Theory Announced in 1838 (57)— Schleiden and Schwann (57)— Johann Muller (58)— Vitalism ( 59)— Virchow's Eu- logy on Muller (60)— Ysars of Discovery (58)— Virchow and "Cellular- Pathology (60) — The Discovery of Protoplasm by Dujardin (61)— Proto- '".^i',"' P.**'"':'* ^^ Starling (62)— The Cell TY?Ty at the Present Time -,:;.•; — i ne r-iiiiciis (uo, — iiiusiration or tne (.eil and Cell Division (64) The Cell in Heredity (65). "There is no knowledge so useful to man as knowledge of himself. Health and happiness are promoted by it. Before the advent of the modem scientific spirit, biologic knowledge was required to conform to the dominant superstitions of the time. The human body was regarded as a peculiar and awful thing, and not amendable to the laws which govern tne rest of the universe. Then it was found that the mechanics of the body are entirely reconsilable with the principles of physics. Humanity's debt of gratitude is incalculably great to those men who at the risk of their lives and fortunes made dissec- tions of dead bodies of men and animals, and discovered the mechanism of the mu.scular system which imparts motion to the joints, the valvular and pump-like arrangement of the heart, and the hydraulic principles of the tubes ,vhich convey the blood through the body. Then came those students of the secrets of nature who discovered that the same laws which govern man govern the lower and the lowest of creatures ; that between soil and mineral, fluids and gases, plants and animals, there is no dividing line; that the lily is the daughter of the pool, and the man is the brother of the ox. This knowledge was gotten for us, not by the philosopher among hi.s books, but by the patient investigator who went to the heart of nature and studied her secrets."— J. P. Warbasse. CHAPTER t. THE CIRCULATION OF THE BLOOD-WII.LIAM HARVEY "This man livofl in an ace when al.h* ly was nu.re im.iular than acMence and the love of mystery stronger than the love of philosophy."— Gorton. "History is simply the biography of the mind of man; and our interest in nistory, and its edu(ational value to us, is directly proportionate to the comidete- ncss of our study of the individuals through whom this mind has been manilCsted To understand clearlv our positions in any science today, we must go hack to its beginnings, and trace its gradual development, following out our laws, dillicult to interpret and often obscured in the brilliancy of achievements-laws wliich everywhere illustrate this biography, this human endeavor, working through the long ages; and particularly is this the case with that history of the organized experience of the race which we call science."— Sir William Osier. . „'^'^* Renaissance— The renaissance, that transitional movement ni Europe between the mediaeval and modern world, affected medicine and the sciences at a much later date than art and letters It begar with Petrarch and the humanists in the fourteenth century in Italv' where it became manifest in painting: and sculpture The movement was accelerated in the sixteenth centu v bv the capture of Constanti- nople by the Turks in 1509, and the dispersion of its r,reel< scholars to the shores of Italy, which event opened anew the science and learn- ing of the ancient world at an hour when the intellectual energy of middle ages had reached its ebb. It is significant to note that Flor- ence, so long the abode of intellectual freedom and art, welcomed with extended arms the exiled Greek scholars. Her traders returned from the East with ancient manuscripts as the most valuable portion of their merchandise. But we are more immediately concerned with the movement as it affected medicine and its allied studies. However much the new learning promoted literature and art, its influence was anything but favorable to the progress of science. Admiration for the literature of ancient Greece while it engendered a love for poetry, history and philosophy, had a similar effect in promoting a spirit of veneration for the writings of Hippocrates, Ptolmev and (ialen, so that it became almost an act of impiety to question their teachings. It was not until the sixteenth century, as we shall see, that the spell of ancient authority was broken by the direct appeal to nature. It was rot until then that the anatomi;-.t determined at all cost to exam- ine the human body for himself and to be guided by his own obser- vations. Anatomy and Physiology— -As anatomy precedes physiology, in order to adequately appreciate the work of Harvey, a brief account of the progress in anatomy is necessary. The great anatomist of an- tiquity, who surpassed all others, was Galen (130-200 A. D.). He lived for a time at Pergamos and for five years at Rome. He was a i::r.:; -: L,';:,;;i vvi:: ;:.- v.-:^-.-!;; vcr ailU V.iitcr. ili.-, VViiiings eillUOUy aii the important anatomical discoveries of his predecessors, enriched and much enlarged by the results of his own originalitv. His observations however, were made upon the lower animals on the faith of which he I'ATHFINDEIfS OF PHYSIOLOGY cxpduiuk'd the human subject. Huxley declares that "No one can read (ialtn's works without beinjr impressed with the marvelous ex- tent and diversity of his knowledge and by his clear jjrasp of those experimental methods by which alone physiology can be advanced." Rome was the field of his greatest triumph as physician. So great was Galen's influence that for more than a thousand years his worka held undisputed sway over anatomical teaching until a greater name arose in the person of Vesalius. Vesalius, born in Brussels the last day of l.")! t, inherited from an ancestry of learned men a keen appe- tite for scientific learning. His was that independent, liberty-loving mind which has characterized his countrymen before and since his day. The great importance of his work lies in the fact that he over- threw adherence to authority as a means of arriving at truth and employed instead, observation and reason. Slavish obedience to author- ity characterized the thought and methods of the Dark Ages. This was in accord with the ecclesiastical influence dominant during this long period. It was the method of the theologian, which had. un- fortunately, survived almost to our own day. Darwin was perhaps ■he most recent object of theological invective. As the Scriptures were an infallable guide to spiritual truth, so the works of Galen were unfailing guides to scientific truth. Vesalius was bitterly oppo-sed not only by the ecclesiastic forces, but by medical men of his time. The theologians opposed him because, among other things, he differed from the widely accepted dogma that man should have one less rib on one side because according to Scripture Eve was formed from one of Adam's ribs. He was also at variance with them on the subject of the Resurrection bone. Vesalius was willing, how- ever, to leave the matter with the theologians, since it did not appear to him to be an anatomical question. Sir Michael Foster writes that Vesalius "Tried to do what others had done before him — he tried to believe Galen rather than his own eyes, but his eyes were too strong for him ; and he cast Galen aside and taught only what he could see and what he could make his students see, too. Thus he brought into anatomy the new spirit of the time, and especially the young men of the time answered with a new voice." It is said that students flocked to his lectures, his audience amounting to some five hundred. The history of anatomy precedes that of physiologv as a logical sequence The work of X'esalius placed the structure of the human body in a new light. William Harvey was the first man to study and proclaim the func- tion of structures which Vesalius had in such a masteily manner demonstrated. "The work of Harvey," says Locy, "Was cnmplemental to that of Vesalius and we may safrly say that, taken together, the work of these two men laid the foundations of the modern method of inves- tigating nature. * * * In what sense the observations of the two men were complimental will be better understood when we remember that there are two aspects in which living organisms should always be considered in biological studies; the first, the structure, and then the use that the structures subserve." iiie new ieaiiung .;pread over Europe in a westerly and northerly direction. England was the last to partake of its benign blessing. England had bui two universities— Oxford and Cambridge; France WILLIAM HARVEY had six; Germany eipht; Italy sixteen. Medicine was a prominent department in all ct' them Compared with the reception accorded literature and philosophy, science lajrjred in Enjrland. (Jreen sums up the situation (Kilo): "Bacon had already called men with a trumpet voice to such studies. But in England, at least, Bacon stood bet ore his a^e. The heKiiinings of physical science were more slow and timid there than in any country of Europe. Only two discoveries of any real value came from English research before the Restoration — the first, Cilberfs discovery of terrestial majrnetism. in the close of Elizabeth's reign; the next, the jrreat discovery of the circulation of the biood which was tai'ght by Harvey in the leign of James. Apart from these illustri'.iis names Enplane' tooK little share in the scien- tific movement of the continent; and l.^-r whole energies seemed to be whirled into Mie vortex of theolo.Q:y and politics by the Civil \Var." Birth and Education— William Harvey was born in Folkstone England, April 1st, 1578. Very little is known of h]^ early life Hi.s prehmmary education was obtained at his native town" where he ^i!^'^.- *^'f cf ';'^^ , 'ic(iuaintance with Latin. He proceeded to the Kmgs Sc-iool, Cambridge, where he remained five vears, and atterw;u-d, at 10 years of age, entered Caius College, Cambridge, in lo9.5. Harvey even early in his .school life possessed habits of minute ^h-^fn^V""- ?'■'; *°»''"«'--i:^. f""- (i'ssections and his love for compara- tive anatomy had shown his mental bias from his earliest vears To Caius, the founder of the College at Cambridge, is accredited the in- troduction into England of the study of practical anatomv. He ob- tamed for hi.s college a charter which allowed the authorities of the insiitution to take annually the bodies of two criminals comemedo death and executed at Cambridge, free of all charges, for JEe purposes of dis.section with the view to increase the knowledge of medicine and to beneht the health of her majesty's lieges, wiThoS Efer- av'.LTi sHf^"f^f '"•^' '/ ^'' '^'''T- To ^vhat extent the o lege availed itself of the pnvilege is not known. In all probabilitv Har- o?7reet"frH^I T''' 'J ''""-f'' '"^"^^ ^^"^''^^^^ '^ ^ s'ound knowledge dL?eetn 1 V.7 i" «rdinanly to owed until he obtained his B. A. degree m iyj7 A year alter graduation, at the age of tvventv we find hum traveling on the continent where he studied the sden'tific branches tributary to medicine, as well as medicine itself A "has thf'n!« 1' the.i.niversities of northern Italy were the first to ^v^lcome the new learning as it emanated from the east in the minds of Greek Prn'?'T' '"' ^'"^ Vt-^'"'^ manuscripts. The universitS of north- « tJl h' trV^'.?"-"^''- ^^^"^' ^''''' ^"^ P^^-'^- ^-^re at the time at the height of their renown as centers of mathematics, law and medicH •'. Harvey s udied more particularly at Padua, renowned for Its anaiomica school, and rendered famous by the work of such men as Vesahus the first of modern anatomists, and his successor, Fabri- cius. The tolerance shown towards Protestants in Padua, the univer- sity town of Venice, tiie great commercial republic, attracted many law and medical students from England and other Protestant coun- tries ot Europe. It is interesting to recall that each entry in the universitv (Pa- dua) register was accompanied by a note describing some physical pecularity of the student, as a means of his identi^cation. Thus Johannes Cookaeus, Anglus cum cicatrice in articulo medii digiti die I'ArilFINDlCrtS OF I'lIYSIOLOGY •lictii. John Cook, an Enp:lishman, with a scar ovor the joint ot his niiddK" finKcT. (Matriculated) on the same day. and so on. Harvey .•videntiy did not enter Padua University as a regular matriculant, as no sucli rvcon\ occurs on the university register regardinjr him. Fabricius and Harvey Irieiuls— The fame of some of its medical teachers iindoubt-dly .ittiacted Harvey to Fadua. While there he was instructed in anatomy and physiolojjv bv Fabricius, one of the most learned scholars of Italy. The fame as' anatomist and surgeon of l^abricus ab Acjuapendtnte (from the name of his birthplace) had spread well over iuiroj).'. During Harvev's soiourn in I'ndua he and tabricuis became fast friends. At that particular time Fabricius was engaged m perfecting his knowledge of the valves of the veins. His idea was that these valves prevented over-distention of the ve.s- .sels when the blood passed from the large to the smaller veins, while they were not re(iuired in the arteries because the blood was always m a state ot ebb and flow. Harvey, however, pointed out their true importance a.s anatomical proof of the circulation of the blood It was not so much what Harvey learned from Fabricius, as the stim- ulus of his friendship that proved of such great assistance to him, lor we can see even in the instance quoted his view of the purpose of the valves of the veins was entirely incorrect. In lf)02, Harvey was graduated M. D. from Padua. His diploma conferred upon him the degree of Doctor of Physic, with leave to practice and teach arts and medicine in every land and .seat of learn- ing It further stated, that "he had conducted himself so wonder- lully well in the examination and had shown such skill, memory and learning that he had far surpassed even the greatest hopes which his examiners had formed of him. They decided, therefore, that he wa.s skillful, expert and most efficiently qualified both in arts and medicine, and to this they put their hands unanimously, willing; iv and with complete agreement and unhesitatinglv." The University of Cambridge conferred the degree of M. D. on him the same year. " Harvey married in 1604, the daughter of Dr. Browne, who was physician to Queen Elizabeth and to James I. Harvey, as we shall see. excelled as lecturer. His lectures showed an intimate acquaintance with the anatomical structure of more '.han sixty kinds of animals, as well as a thorough knowledge of human anatomy, which must have taken vears of study to accjuire He was elected fellow of the College of Phvsicians in 1G07. An im- portant position which Harvey held was Phvsician to St. Bartholo- mew's Hospital in KJOO "The charge of the Phvsician of St Bar- tholomew's Hospital" required the incumbent to devote at least one day a week througlioul the year to charity. He was further enjoined, "not for favour, lucre, or gain, to appoint or write anvthing i'or the poor but such good and wholesome things as he shall think with his host aiivice will <\n ilie poor good, witliout any aiicction or respect to be had to the apothecary. And he shall take no gift or reward of any of the poor of this house for his counsel." This "charge" Har- vey is said to have faithfully observed. -\naiomicai ieacinii^ i"ie\ious iu 1745 — During Harvey s day ard until 1745, the teaching of Anatomy in England was vested in a lew corporate bodies. Private teaching was discouraged by fine and WILLIAM HAUVEY g imprison men t The OAjvi:,- of Physicians •ui• ^^y ■'' ^^'^'^ «f ci'-monstrations on the bo3v. Ihe absence of means of i)reseryation of cadavers precluded instruc- tion in de ail. A single body was dissected to shoJ the mures an- other o demonstrate the bones, and a third to exhibit the' yiscer A tendance on anatomical lectures and demonstrations was com-' pulsory; violation meant the forfeiture of a fine. Some were ex- empted from the penalty, as one entry shows that a Robert Mudslev has licence to be ab.sent from all lectures without pavment of an'v onlv ^'Tl f Kiven over the art of surgery, and doth occupV only a silk shop and shave. The anatomical demonstration,'? were open to the public The following note appears in Pepy's Diary:* "Up and to my "off ice . . . , Commissioner Pett and I walked to Chyrurgeon's Hall (we being all invited thither, and promised to dine there): where we were led into the 1 heater; and by and by comes the reader, Dr Teame hll^ f.T^'^u'' t""^ ^o^TP'^"-^' '" a very handsome manner; and all being settled he began his lecture, thvs being the second upon the ureters and kjflney.s w-hich was very fine; and his discourse being ended, we walked into the hall, and there being a great store of com- n&ny we had a fine dinner and good learned company, maiiv Doctors 01 Physique and we used with extraordinary great respect 1 . . After ?Jm ''Ti, Scarborough took some of his friends, and I went along Nv h them to see the body alone, which we did, which was a lust? fellow-, a seaman that was hanged for a robbery. I did touch the dead body with my bare hand; it felt cold, but methought it was a very unpleasant sight. . . Thence we went into a private loom where I perceive they prepare the bodies, and there were the kidneys and ureters, etc., upon which he read todav, and the doctor upon my desire and the company's, did show verv clearly the man- ner of the d'--^ease of the stone and the cutting and^ill other questions that I could think of Pepy's interest in the operation oi' cutting for s one is said to be due to the fact that he had undergone the ordeal himself. The Dr. Scarborough mentioned in Pepy's nS"e was a triend and pupil of Harvey. Personal Characteristics— Harvey is described as a man of the lowest stature, round faced, with a complexion like the wain.scot • his eyes small, round, very black and full of spirit, his hair black as a raven and curling; rapid in his utterance, chivalric even to gesture and used when in discourse with anyone to play unconsciously with -Samiiei Penjs (i632-l(ua). was a famous diarist His Diary which pxtends from 1G00 to 1669, was written in shorthand, and was deciphered hy Lord liraybrooke in 1S25, This delightful book of gossip is one of the most interesting memorials of the domestic life of the time. rATHFINDKRS OF PIIYSIOLOCY the small dapper ho wore by his side." His individuality was marked, as was evidenced by tl\' stronp impression he made iiiion those with whom he came in contact. His intellectual jxiwer and mdependence of chara;'ter were unusual. His ii.teiests were wider than his scien- tific studies. Accordinp to an anonymous biopraphcr* ot' the eipht- eenth century. "He was well read in ancient and modern historv; and when he was wearied with too close attention to the stiidv "of nature, he would relax iiis mind l)y discoursinp to his friends on political subjects and the state of public all'airs. He took preat pleasure in readinp from the ancient poets, and especially \'irpil, with whose work he was exceedinply deliphted. He was laijoriously studious, repular and virtuous in his life and had a stronp sense of relipion. In his t'amiliar conversation there was a mixture of pravity ; nd cheerfulness; he expressed himself with preat perspicuity, and with much prace and dipnity; and was eminent for his preat candor and moderation. He never endeavored to detract from the merit of other men; but appeared always to think that the virtues of others were to be imitated and not envied." In spite of his choleric and hasty disposition he had the faculty of makinp close friendships. His replies to his critics showed great moderation. Harvey's true character is probably best seen in that period of his life which was beset with opposition and reproach, im- mediately followinp the publication of his preat work on the circu- lation. To his traducers his attitude resembled that of the divine Master, "To return evil speakinp with evil speaking I hold to be un- worthy of a philosopher and searcher after truth. I believe I shall do better and more advisedly if I meet so many indications of ill- breeding with the light of faithful and conclusive ob.servation." His attitude also resembles that of Darwin who, on the publication of his Origin of the Species, was met with a storm of abuse from clerical ignorance. It is said that tl.c preat evolutionist not only observed a tranquility impassionate and uni(|ue but even condescended to replv at length with courtesy to the rantings of those who vilified without even reading his work or comprehending the object of their denunci- ations. Harvey was not a religious man in the narrow sense of the term despite the fact that he lived in an age of warring creeds. His views were broad as befitted a student of the design and workmanship of the Great Architect of the universe. According to Sir Russell Re.v- nolds, "a devout and reverential recognition of God" permeated his work, "not only as the great primal ever-acting force, defined outside and before all the works of nature; but as the Being, 'the Almighty and Eternal God' to whom he says in his last will and testament, 'I do most humbly render my soul to Him who gave it; and to my blessed Lord and Saviour Jesus Christ.' " Harvey's knowledge of Latin was so thorough that he could con- verse with facility equal to his native tongue. He was accustomed to employ both English and Latin even in the same sentence, for ex- ample, speaking of the eyes and their f'lnction: "Oculi eodem loco, viz. nohihssirrii snnra et ante ad Droce> us eminentes inst.-ir c.T^nifis in a lobster snayles cornubus tactu pro visu utuntur unde oculi a.s a centinell to the army locis editis anterioribus." •British Biographies, Vol. IV., London, 176S. I I WII.MA.M IIAIIVHY 7 Harvey as Ledurer— Harvey's lecturi's were partlv read and partly oral. The cadaver lay on the (able with the dissecting instru- ments close to it. An assistant dissected or demonstrated while the lecturer read his remarks. The anatomical lecturer of the .sixteenth century was a personage of importance. The greatest consideration wa.s e.\ercised for his personal comfort. The stewards were instruct- ed, "to see and to provide tiiat there be a mat about the hearth the hall that the Doctor be made not to take cold upon his feet. * ' * And further, that there be two fine white rods appointed for the Doctor to touch the body where it shall please him; and a wax candle to look into the body, and that there be always for the Doctor two aprons to be Irom the shoulder downward and two pair of sleeves for his whole arm. . . and not to occupy one apron and one pair ot sleeves every day. which is unseemly." Harvey laid down the following precepts tor his own guidance as lecture precepts which the modern anatomical lecturer might observe with propriety: (1) To show as much as may be at a glance, the whole belly lor instance and afterwards to subdivide the parts according to their position and relations. 'd'^ ^^ ^^^"^ ""* ^""^^^ '^ peculiar to the actual body being dis- (;5) To supply only by speech what cannot be shown on your ov\-n credit and authority. (1) To cut up as much as may be in the sight of the audience. (5) To enforce the right opinion by remarlis down from far and near and to illu.strate more by the structure of animals accord- ing to the Socratic rule. (6) Not to praise or dispraise other anatomists, for all did well and there was some excuse even for those who are in error. (7) Not to dispute with others. (8) To state things briefly and plainly. *u i^^} ^^^ to speak of anything which can be explained without the body or can be read at home. Here we have a combination of orthodox medical ethics and sound pedagogy. Harvey's particular role as ^Lumlian lecturer in- cluded the position of lecturer upon the viscera. Discussing the tho- racic viscei-a he ennunciated the remarkable discovery with which ihViT^ 1^ "^«eP^i-^l^ly .associated, initialing the notes to indicate that the ideas were peculiarly his own. constat per fabricam cordis sanguinem per pulmones in Aortam perpetuo. Transferri, as by two clacks of a water bellows to rayse water. constat per ligaturam transitum saguinis ab urteriis ad venas u.ide perpetuum sanguinis motum in circulo fieri pulsu cordis. Vv. H. f 4n'T^® Lumllan lecture was a surgical lecture established at a cost of Essex Euglan^d '""^ ''"""' ^'""^ ^'^^ '"'°'"' °' "'"'^^ °' "^'^ I^"'^^ o\ 8 PATiiriM)F;ii.s or physiolooy "It is plain from thf struct iiro of the heart that th.' l)l(.mi is passed (•ontimioLisly thruuKli tho lunps to the aorta as t)v the two clacks of a water bellows to raise water. "It is shown by the application of a liRature that the r)assajre of the l)Ioo(i IS trom the arteries into the veins. "Whence it follows that the movement of the blood is constantly in a circle and is brought about by the beat of the heart " It was not until twelvi" years after this important announcement that he proclaimed it to a wider audience. Harvey's literary stvie was somewhat liKurative. He loved to indulge in metaphors— witness: An cerebrum ri'X. whether the brain is kin^. Nervi majistratus, the nerves his ministers. Musculi cives populus, the muscles the, citizens or the people. He also draws a similtude likinj? the brain to a military com- mander, the leader ol an oreliestia, an airliitect, and he sni^aks of the mu.scles and nerves as subordinate otlicers. Year by year Harvey delivered the Lumlian lectures to the Col- lege of I hysicians. His private practice grew so as to be fairly lucra- tive. Harvey and fticon— In 1018 he was appointed phvsicir.n to Jamesl. In l(i;il he was appointed physician in ordinary to King James son, Charles I. Not only gained he an entrance to the house- hold of the king but he was employed in the homes of the most dis- tinguished nobles. Among others he attended Sir f>ancis Bacon, w-ho was always a weak and ailing man with a disposition to be hypo- chondriac. "In William Harvey and Franci.s Bacon," savs Corton, may be observed two men like planets in conjunction: bom in the same generation, each illustrious in the annals of history, the one in philosophy, the other in science but in striking contrast to each other. The one was a thinker, the other was an actor; one con- ceived methods, the other put methods into operation; one was an academic philosopher, the other a man of science and discovery; one immortalized him.self by his profundity of thought, the other by his contribution to science. Both were stars in the firmament of great men, but long after one has become dim or gone out, the other will continue to shine with splendor." Though honored by England's Lord Chancellor as the custodian of bis health. Harvey evidently failed to be impressed with Bacon's greatness even as philosopher, for speaking of him, Harvey refers to him as "writing philosophy like a Lord Chancellor." Publication of His Work on the Circulation— In 1G28, the crown- ing event of his life look place when he published his well considered and matured account of the circulation of the blood. He had demon- strated his ideas of the circulation for twelve vears before publishing them, which event occurred in the fiftieth year of his life. This nonumental work ol the great physiologist was accomplished while vet ;:: ;;i:j i:;:; liL: . w ay x^nrw^y snuuiii aiiOW SO iiiUcii luiie Lo eiiipse be- tween the event of his epochal discovery and its publication is not clear. Evidently the passion to rush into print was not so great as it is with the investigator of to day. It is interesting to note, how- WII.I.IAM IIAliVKY y ovor, th.-it anion^r t^,. greatest ,hiiil«-rs and uuvstiKators Ham-v is '•Tn"d!''.'"nr. '"^T•'^^•Vu^"""^'•"'•■"^ - -".I to lu.v.. .iHamniMs li.ati.x of Kcvolutions thirty years UvinVi- p.. mittiiiK' jis publi- cation; IJaco., kept his Novum Orpamim l.v hm. lor tuvlv'. v.i'.s- •T,*^, . 'm '" .'"■'"""•'' '" -^'l''"^''' over tin. motion of th.. sphrres" /'in "";"!■■ ■'■''',";■' '"■'■'"■'' l'"''li-^''i'U' tns I'rinc-ipia: 1 ..fween h.. Ii.st ,|ralt ami tlu- puLiiralion of t,,. OriKMii of th.' S uriVs sovon- tfyn years uviv prrnutted to intervene. Perhaps it was Harvev's • K aiu-e towani quittniK the peaceful haven," that cnstrain..,! ' 1 <;• .^'. lonjr a tune, tor elsewh.T,. lie t. lis us that hi, praetiee Kll oil or. to use his own words, he "fell mik'htv in practice" Rt- u'nnN''ii "\'^ contemporary wrote, "tli-.u^^h all of his profession uld dlow him to be an excellent anatomist, 1 never he: rd of anv ho admired his th..rapeutic way, I knew several praetii ior.ers in tin; oNvii inat v^ould not have v'iwu thr-e peiici for his i,ilis (pre- scriptions) as a man can hardly tell by his bills what h.' did, aim at " HaiA-ey IS said to have Ik,.,, the lirst to be persecuted bv ihe nK.lual profession lor making discoveries at variance with the drift of public hou..;iil and opniiyn. 'II,.. slory of all discoveries of the (irsi rank has borne out Locke s aphorism thai "Truth scarce ever yet carried •' ^'"';;'' !'/ '■'■•^^ .iPPcarance." The greatest oijstacle to the accept- ance of truth seems to be our present knowl-dge. Men are by nature conservjitive; they re.sent innovations. liaKehot tells us thut the pain ol a new idea is one of the jrreatest pains to human nature" hocrates somewhere likens himself to a midwife but hi ; peculiar lunction in lile was to assist in that mental labor which rave birth to ideas, a similitude which is suK;,'estive of pain. The man who ex- pres.ses a new idea is apt to be abused, perhaps stoned. Whatever may be said ot the twentieth century the scientific world c.'.n be ac- cused iiu louKvi Ol tardiness in the acceptance ol new truMi but it re.serveslhe li^rht to "prove 1 thin,-; and to hold fast to that which IS Kood. W hile Harvey's practice may have fallen olf, his discovery did not by any means consijm him to obscuritv. He still found favor with Kiiiif Charles I, whose personal physician he was Hi- constant attendance at court greatly interfered with his duties at St Bar- tholomew's Hospital and resulted in the appointnunt of an assistant hut with no diminution in Harvey's stipend. A c.nlemporarv of Har- vey states as follows: "1 have heard him sav that after his Booke of Cuculation of the Blood came out he fell m'ij,'htilv in practice and 'twas believed by the vulgar that he was crack-brained, and all the physicians were against him, with much adoe at last in about twenty or thirty years' time it was received in all the universities of the world, and m< !)r. Hobbs says in his book 'De Cuipore." he is the only man perhaps that ever lived to see his own doctrine established in his liletime;" Veritas est magna et prevalebit! And yet, after the discovery has been recognized as one of mo- mentous import, the scientist has his detractors. Harvey was no ex- ception. There were those who sought to disprove the orii'inality of his work. Some attributed the merit of discovering the circula- tion to Scrvetus, some to Roaldus Colurnhup. other-, f:-. d-.i^^^lr-.i^.::^ True, Servetus, a Spaniard, bom in 1511 and' bunied at the sTake^in Geneva, 1533, at the bidding of Calvin, in a copv of his Restitutio, which was saved when an edition of 1,000 copies met the fate of the author, rejected the contention that the blood passed through the 10 rATIIFINDKHS OF PIIVSIOI.OCY cnnii.-ic septum. Fir had jrruspfd tin- true fcaliircs of the pulmonary circulation— I hr pas-aye of the 1.1.,..,! from the riKht .side to the lutiKs, thence to the left side or ventricle. Fiealdus Columbus, born at Cretiiona, l.')l(l, a presumptuous personajje, speaks of the blood carried, "!)>■ the artery-like vein to the lun>r and l)einjr there made thin is brought back thence together with air by the vein-like artery to the left ventricle of the heart." Then lu' Koes on to press his claitn by dt clarin>r that, hitherto, no one had made this observ.ation or re- corded it in uritin^r .Andreas Caesalpinus was born at Arezzo in lol'.t. He held for many years the professorship of medicine at I'isa, Learned in all the lore of the ancients, he was rioted amontr other things for his determined oi)po.sition to Galen; Caesalpinus appears to have jfrasped on" important truth, namely, that the heart at sy.-tole disch.irKcs its contents into the aorta and pulmonary artery, and at its diastole receives blood from the vena cava and pulmonary vein. Let all this be j^ranted, yet the trreat work of Harvey is not a whit less meritorious. The steam enKine was in existence before the day of .1; les Watt, yet his name is inseparably associated with the invention which transformed a mere toy into a KiRimtic factor which has revolutionized iuiman industry. No person, not even the jrenius is independent of his time; he is the heir of all the ajje.s, and his K'cat- ness does not depend so much in presentinjr something unprecec'ented a.s it does in seeing something clearly and telhng in a simple way what he has seen. Treatise on the Circulation. — Harvey's greatest work was un- doubtedly his Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus, an anatomical treatise on the movement of the heart and blood in animals, published in Frankfort. (Jermany. in lfi28. The book was a small <|uarto volume of 72 pages. It (;pens with a dedi- cation to "The Most Illustrious and Indomitable Prince, Charles. King of Great Britain, France, and Ireland, Defender of the Faith," etc. The dedication proceeds: "The heart of animals is the foundation of their life, the sovereign of eveiy thing within them, the sun of their microcosm, that U])on which all growth depends, from which all power proceeds The king in like manner, is the foundation of his kingdom, the sun of the world around him, the heart of the republic, the fountain whence all power, all grace doth flow." Whatever may be .said regarding Ch.arles I. who was the victim of public execution, he certainly befriended Harvey. Then to the president of the Royal Col- lege of Physicians and to other learned ph,\sicians the author ad- dres.ses himself in a dedication which he concludes: * * * "I profess both to learn and to teach anatomy not from books but from dissec- tions; not from the positions of pliilosphers but from the fabric of nature. * * * I avow myself the partisan of truth alone; and I can indeed say that I have used all my endeavors, oestowed all my pains on an attempt to [iroduce sometning that should be agreeable to the good, profitable to the leai'ned, and useful to letters " Harvey's method here ennunciated is tli2 method of every .-.cienust since his day. whose contribution has possessed real merit — that is, reasoning based upon experiment and obser\'ation. The work on the circulation comprises seventeen short chapters. It is an interesting account, lucid and connected, of th i heart's action and the circulation of the blood. Harvey had no means of knowing WILLIAM IIAKVKV It til.' ciiiin.'ctidii h.twcin tli.' smallest artrrit-s ami I lie smallest veins, ('(ir the microscdpc was not in such a sta^e of perfection as td permit of miicli line work in minute anatomy. It was not until the invention of the compound microscope in i(;75 that Leeuwenhock (lescrihed hlood corpuscles and the capillarv circulation. In the (irst chapter the a'lthor review.s .some of th.. fantastic theories rerardinjf t.ie functioninjr of heart and lunr^. The heart was held to he the Kf-eat heat center .,f the l.o.ly The hlood Was sucked into it durinir diastole and ...xp,. II d fn.m it durni>r systole. The arteries cooled the l)l<)od: the lun^s tanned and cook-d the heart. The term "spirits- meant a Kt-eat deal to Harvey's predece.s.sor.s, hut not to hitn "The \v()rd l)loo(l has nodiMiK of Krandilotiuence ahout it. for it si^rnities a .substance which we have before our eyes and can touch; hut tu.fore such tjtles as spint and calidum innatum (inherent heat) we stand Sifape. Ch 'pter I, he continues: ••VVlH.u I tit-Hi K!i\o my mind to vlvlsP-tlons, as a mpnn.i of rt'eoov. ItiK the motions an.i us.s of tlio h.art. and soiikI.i to dla.ov.T tlirs.- from icluiU inspoo- tlon, and not from .1... vsritln«« of others. I found the task ho iriilv arduous so full of diin.ulth.s. ttiat I «aH almost tempted to think. «iih PraraslnrluH, that the motion of the heart was only to be comprehende' by God. For 1 could neither rightly perceive at first the systole and when the diastrle to ,k pla, e. nor when and where dilatation and contraction oc, urred. by reason of the rapidity of the motion, which In many animals is accomplished In the t«ink!iii>; of an eye comInK and ^oing like a flash of linhlnlng; so that the sy.stole pre.seiiied ii.elf to me now from this point, now from that: the diastole the same; aii.l ih. ., very- thing was icwrsed, the motions occurring, as it seemed, variously and coiiiusedly together, * • • "At length, and bv using greater and daily diligence, having fre'iuent re- course to vivisections, employing a vailety of animals fo- the purpose, and collat- ing numerous observations, 1 thought that I had attained to the truth, that I should extricate myself and escape from this labyrinth, and that 1 had discovered what I so much desired, both the motion and the use of the iieart and arieries, since which timo 1 have not hes.tated to expose my views upon these -i'lhjects, not only in private to my friends but also In public, In my anatomical leciuros after the manner of the academy of oid." He goes on to tell how his view.s pleased some, displeased others. He finds it advantageous to study the movement ^^f tlie heart in the cold-blooded animal.s— frogs, snakes and fishes. He ascertained that the heart was a muscular organ, that its systole was the result of muscular contraction. The contraction of the heart was more im- portant than its dilitatlon. "During its contraction the heart becomes erect, hard and diminished in size, zo that the ventricles become smaller and are so made more apt to e.Kpel their charge of blood. In- deed, if the ventricle be pierced the blood will be projected forcibly outward at each pulsation when the heart is tense." Harvey showed that the pulsation of the arteries depended upon the contraction of ■.:;t; ;c; ■_ vciiiiii;;;;. i ::c 'C'-j::iili'Ciiuii UI ine ri^nt VCiiuiicie piupeiied 'Tho extracts which follow Illustrate H.irvf.y's style. The Motion of the Heart anrl Blood, by William Harvey, can le procured In convenient form In the Everyman's I.ihrary Series (E. P. Dntton ,t Co.. N>w Vorki Tlil^ Is a reprint from the Sydenham Society's edition of 1847. n 12 I'ATIiFi.VDlJKS OF FHYSIOLOCY tho blood into tl;e pulmonary arteries, the pulsations of wliich were simultaneous with the other arteries of the bodv. He demoiistrated that the two ventricles contracted simultaneouslv and that the two auricles contracted at the same time. Motion, Action and Ollice of the Heart.— In the fifth chapter Harve.v deals with the motion and function of the heart. It read.5 somewhat like m modern work in physiology. "Fir.-t (.1 all, ilu:- auric-U- coiilracts. aid in tin- cours.' of its coim-atlioii lUrows the blood (whicli it contains in aiiipK. quantity as the head of the veins, I he storehouse, and cistern of the blood j, into the ventricle, which, beinj; filled, the heart raises itself straightway, makes all its fibres tense, contracts the ven- tricles, and performs a beat, by which brat it immediately sends the blood sup- iWied 1(1 II 'la ilie auricle into the arteries; ,he right ventricle sending it,s charge iiito the lungs by the vessel which is called vena-arteriosa, but which, in s'ructure and fuiifiou. and all things else, is a., artery; the left ventricle seuding its (hargc into the aorta, and through this bv the arteries to the bodv at large. These two motions, one of the ventricles, another of the auricles, take iil.'ce con- secutivel;-, but in sucii a manner that there is a kind of harmony or rhythm pre- served between them, the two concurring in such wise that but one motion is apparent, especially in the warmer blooded animals, in which the movements in question are rapid," So far as Harvey's reasoning is based upon his observations his conclusions are in the main correct, as proved by more recent re- search ; where he indulges in speculation we get the following: "In the larger and more perfect animals of mature age Nature has rather chosen to make the blood percolate the parenchyma of the lungs. * '■ * It must De because the larger and more perfect animals are warmer, and when adult their heat greater, ignited I may say and requiring to be damped or mitigated, that the blood i.s" sent through the lung.s. in order that it may be tempered by the air that IS inspired and prevented from boiling up aiid so becoming e.xtin- guished or son ething else of the sort," or, to modernize it. the lungs sei-ve a.s radiator and the heart the gasoline or internal combustion engine. Capillary Circuhition.— Since Harvey';i time Malpighi, in 16G1, hinted at the capillary circulation, which was still further investi- gated by Leuwenhoe'k in 1(J71. who studied it with his microscope in the web of a frog's loot and in other ti-ansparent membranes. In 1G7G. Biankiiart, and in lo97 Cow per, tudied the arrangement of the capillaries by means of in.jecied specimens. A long interval elapsed bctueen the hisioiogical study of the circulation before chemistry v.;is sulliciently ativanced to afford definite knowledge in regard to oxidation of the l)lood and the explanation of the true function of the lungs. The work of Priestly in 1775 was a notable contribution to the physiology of respiration. The nineteenth century, through the work of Ludwig in Germany, Chauveau in France, and Foster in England, has seen the physics of the heart and circulation reduced almoi't to an e.xact .science. AnV acCt'>Unt of tlie work.-^ of TT'lWi'V \v;~;!!l;l ]•.:■ \^^r:':ir\r\)iii:^ •,1'pr^i no mention made of his work in embryology. Harvey discussed the nature of development and exhibited extraordinary powers as re- WILLIAM IIAltVKY 13 Kurds accuracy of reasoning. He may be considered as having made the first independent advance in the subject. That lie did not ac- complish more was (hie to lack of instruments of precision, and to the fact tluit he had to build on the general level of the science of the time. His work on embryology was published in IGol. It was entitled "E.xercitationes de (Jeneratione Animalium." In it is an account of not only the development of the chick, but of deer and other mammals as well. All honor to liim who blazes the trail. The refinements, what- e\ei- tiu,, may be, can never merit for the investigator the honor wii'ch IS due the pioneer. As was said by Haller, one of the best informed minds of the eighteenth centurv. "It is not to Caesalpinus because of some words of doubtful meaning, but to Harvey. +he able writer, the laborious contriver of so manv experiments,' the staid oropoiinc er ot all the arguments available in his dav, that the im- mortal glory of having discovered the circulation of the blood is to be assigned. One of his last acts was to set a-ide a certain sum derived from his estate for the delivery of an oration in commemoration of the beneffictors of the College of Physicians. This oration, the Har- veian Oration, is sMll delivered each year by some distinguished mem- ber of the medical profession. Even in his declining v^ars his thoughts were turned to the future. The Harveian Lecture is in- tended ^o further the progress of .science, especially a knowledge of the body in health and disease. "Much of the nobility of the profes- sion, ' .says Osier. Harveian lecturer, 190G, "depends 'upon the great cloud of witnesses' who pass into the silent land— pass and l^ave no sign, becoming as though they had never been born. And it was the pathos of this fate not less prophetic because common to all but the few, that wrung from the poet that sadly true comparison of the race of man to the race of the leaves." Harvey was one of the "few" to have achieved that immortality which places him with "The divine men of old time." He died June 3rd, 1657, in the eightieth year of his age. Asellius and the Lymphatic Circulation. Corollary to the circulation of the blood is the lymphatic circula- tion. The discovery of the lymphatics was almost s'ynchronou.s with that with which Harvey achieved an immortal name. While the niemory of Harvey has been fittingly honored in various wavs. that of Aselhus or Aselli has not been sufficiently recognized. The data referring to Aselli's life are extremely meagre. He was born in 1581, it Cremona, Italy, the descen;lant of a iiatrician family. He studied at the I niversity of Pavia, v.'.n-e lie became laureate in medicine, rurgery and r-liilosopliy, a^'.er uliich he located in Milan, where he taught anatomy private-!/ and engaged in the practice of surgery. It w-as while in Milan '.nat he made his discoverv. in 1G22, of the Ivm- phatic vessels w^xch he called venae lactae. His discoverv was rec- ognized by his election, two years later, to the chair of anatomy and ourg;.ry in n;.-, aima iiialfr, a position he was destined not long to hold, for he died in 162G at the age of fortv-five. His book De Lac- tibus was published a year after his death. William Harvey was 14 PATHFINDERS OF PHYSIOLOGY forty-four years old at the time of Aselli's discovery. Asclli's dis- covery the hicteals is related by himself as follows: "On the 23r(l of July in thar yoar (1022) 1 had takon a doK In K()od condl tlon and well fed, for a vivisection at the request of some friends, who very mueh wiKhed to sec the recurrent nerves. When I had finished lliis leuioiistra- tlon of the nerves, it seemed good to watch the movements of the diaphragm In the same dog, at the same operation. While I was attempting this, and for that purpose had opened the abdomen and was pulling down with my hand the intes- tines and stomach gathered together into a mass, I suddenly beheld a great number of cords, as it were, exceedingly thin and beautifully white, scattered all over the whole of the mesentery and the intestine, and starting from almost innumerable bc:?innings. At first I did not delay, thinking th.-m to be nerves But presently I saw I was mistaken in this, since I noticed the nerves belonging to the intestine were distinct from these cords and wholly unlike them and besides, were distributed quite separately from them. Wherefore struck bv the norelty of the thing, I stood for some time silent wl 'e there came to my mind the various disputes, rich in personal quarrels no ler han in words, taking place among anatomists concerning the mesariac veins ....d their function. And by chance it happened that a few days before I had looked into a little book by Johannes Costaeus written about this very matter. When I gathned mv wits together for the sake of the experiment, having laid hold of a very sharp scUpel I pricked one of those cords, and indeed one of the largest of them I hrl scarcely touched it, when I saw a white I'quid like milk or cream forthwish gush out. Seeing this, I could hardly restrain my delight, and turning to thos» who were standing by, to Alexander Tadinus, and more particularly to Senator Sep- talius. who was both a member of the great college of the Order of Physicians and, while 1 am writing this, the medical offlcer of health, 'Eureka,' I exclaimed with Archimedes, and at t'le same time invited them to the interesting spectacle of such an unusual phenomenon. And they indeed were much struck with the novelty of the thing." AselH noted the presence of valves in the lymphatic vessels and [hpTvmn'l H "■ ^""'^^Jo"' namely to prevent the backward flow of the lymph He recognized also that the lacteals were vessels for con- veymg chyle away from the intestine. He went wrong, however in regard to the ultimate course taken by the newly-di.scovered vessels for he thought he could trace them to the liver.' Aselli was helvilv handicapped b,v his previous learning, which consisted of a careful study of as well as veneration for the teachings of the ancients Galen had, in fact, taught that all nutritive material frim digestive processes passed through the liver. Aselli speaks in his book of a group ot lymphatic glands lying in the mesenterv, as the pancrea.s— ^?n? f fi,"T^/'^"fu*'''^' '^'''"•- ^^° ^"'■c*^ ^-hich cau.sed the move- ment of the fluid in the lacteal vessels was believed bv him to bo two- fold a VIS a tergo and a vis a f rente; the latter derived from supposed inteSes ' ^'''™''^ supplied by the movements of the nrnv^fW^S^T'l ''•T "^"■'■^^;- ••^'*'"' '" ^'« modesty endeavored to h™)!-! a ^ ''"'! ""'."'^ '^""''■" ^0 ^'^'^ ancients, especially to !;Ih;?=^ ■L.^"'?:,^^!^.^':!^'''*^"-':/^""'^^"'''^ of the Alexandrine school of f^^^lu^ '''' ■-••"'■"■'■'"•'-■*■'' '""^■^ ^'^r.c .-..me oppu.-iiiioii as did Harvev's, and from the .sam.' men, among them Riolan and Primrose, and strange to say Harvey him.self fail, >] to recognize the importance of the work ASELLIUS 15 of his contemporary, writes : In a private letter written in April, 1652, he "With regard to I ho larfoal veins discovered by Aselli, and ty the further diligence of Tecquet, wiio discovered the receptacle or reservoir of the chyle. and traced the ranals thence to the sub-clavian veins, I shall tell you fr>^ely, since you ask me, wh,.c I think of them. I had already, in the course of ray dissections, I venture to say even before Aselli had published his book, observed these vhlte canals. » • » jjut, for various reasons, and led by several experiments, I could never be brought to believe that that milky fluid was chvle, conducted thither from the intestines, and distributed to nil parts of the body for thoir nourish- ment; but that it was rattier met with occasionally and by accident, and proceeded from too ample supply of nourishment and a peculiar vigor of concoction;" and Harvey continues: "Why indeed, should we not as well believe that the chyle (digested contents of the intestines) enters the mouth of the mesenteric veins and in this way becomes immediately mingled with the blood, where it might receive digestion and perfection. • • * And that the thing is so in fact, I find an argument in the distribution of innumerable arteries and veins to the intestines, more than to any other part of the body, in the same way as the uterus abounds in blood vessels during the period of pregnancy." Sir William O.sler (Harveian oration, 1906) refers to this inci- dent in Harvey's career: "How eminent so ever a man may become in science, he is very apt to carry with him errors which were in vogue when he was young — errors that darken his understanding, and make him incapable of accepting even the most obvious truths. It is a great consolation to know that Harvey came within the range of this l;iw — in the matter of the lymphatic system; it is the most human touch in his career." The lacteals were demonstrated in man in 1628, the subject be- ing an executed criminal examined shortly after execution. Twenty- one years after Aselli's death the thoracic duct was discovered by Johannes Pecq'.'et, of Dieppe, France. He not only accurately de- scribed these lymphatic structures, but showed that Aselli's lacteals poured their contents into what he called the receptaculum chyli, but that the thoracic duct — a continuation of the receptacle — poured its contents into the venous system at the junction of the jugular and subclavian veins. Pecquet was twenty-five years old when he made this discovery, which he himself described as the gift of fortune sporting witn the ignorant. Munus est fortunae cum in.scio ludentis. Pecquet, however, did not follow up this solitary triumph. His ap- petite for alcoholic beverages got the better of him and eventually caused his death. Harvey's work on the circulation appeared between the discov- ery of Aselli and that of Pecquet and so profoundly had it influenced the medical thought of the time, that the discovery of the thoracic duct and its function was accepted without question. 11 C H A PTi: 1{ 11. physiolo(;y of digestion in the seventeenth and ekihteenth ( entiries The circulation of the blood was worked out and proclaimed to the W(jrld by one man, and his work was so complete that it has not been rendered obsolete by subsequent knowledge. The historv of the physiology of digestion has been of gradual growth so that' no one man can claim credit for our present knowledge. liefore the develop- ment of chemistry, any marked progress in the ph.siolo^v of alimen- tation would not have been possible; the earlv workers in this par- ticular field were chemists rather than phvsiologists. The history ot physiology during the seventeenth and eighteenth centuries in- volves the lives and work of numerous investigators, each accomplish- ing all that was possible considering the advancement of the general scientific knowledge of the time. f *u^^'" ^y^"^^^ of the latte ' of the seventeenth and earlv part of the eighteenth century a iminent as e.xerting im])ortant intl- ence in the way of solution ,;i th chemical prot)lems of phvsiologv These were George Krnest Stahl and Hermann lioerliaave. Stahl was born at Anspach in lG(i(); he stuilied at Jena, and after graduating be- Ciime court physician at Weimer, aiui in 1(511 1 professor of medicine at Halle. He died m 17:M in IJeilin. where he moved in 1716 on his ap- pointment as physician to the King of Prussia. Stahl was an ac- comphshed chemist of his day. His views on gastric digestion may be summed up in the following sentence from his work: "Some people suppose that gastric digestion results from the action of particular and specific ferments, and indeed go so far as to regard the st.miach as not only the seat but also the origin of a particular ferment, whereas in the whole construction of the st(jmach nothing particular IS ob.served which would render the elaboration of such a special agent likely." He was a th-m believer in the psvche of Aristotle and introduced a principle which lie termed anima. He was whollv out of sympathy with those who tried to e.xplain the phvsical and psychical phenomena of life and mind on chemical and mechanical principles. He could not think of himself as a chemical retort subject to ferments. The soul was to him the living force of the body; "It was susceptible of being played upon by a thousand dilferent" influ- ences, such ,i.> joy. sorrow and grief, love and friendship. Uw beauti- ful, the true, the reverent, the sublime. * - * Can these things be the product 01 chemical acids and alkalies and the mechanijal devices of the mason and builder?" Sir Michael Foster sums up the teaching of Stahl thus: "Learn as much as you can of chemical and phvsical pro- cesses, and in so far as the phenomena of the living bodv e.xactly re- semble chemical and physical events appearing in non-living bodies you may explain them by chemical and phvsical laws. Cut d( not conclude that that which you see taking place in a :ion-livinir body v.iii laivc (/iace m a Iimhk i)0(i\, for the iiemicaf and phvsieal phe- nomena of the latter are modified by the s. ul. The events of the bodr may be rough hewn by chemical and i)hysical forces, but the soul will PATHFINDERS OF PHYSIOLOGY K Shape tlu'm its ou ii end and will do that by its own instrument, mo- tion Mahl, It wdl be seen, belonged to the '■vitalists," which nar- ticu ar type „i phy-ioloRist has only witriin recent vears become ex- tinct. His Imidamental position was. between livinjr and non livinir ,&' l^'^'''''':' m'at Rulf lixed. Living things so long as thev are alive are actuated by the sensitive soul; non-living things are not Ihe rational soul of man governed his whole bodv. The healing power ol nature, vis medicatrix naturae, has been recognized from the most ancient to the present time. Stahl's svstem was founded upon the .sui)po:-ition that the vis naturae existed entirelv in the ra- nr!m' rrtw f^'^r'''''"'"'? "^ ^^"^''' ''^'^trine. he and his followers piop.j.sed the art ol curing by expectation, medicina expectans which practice led to the prescribing of inert remedies, placebos ' fhP ™''f"'' /'"'""'•''•-I" the catalogue of workers in phvsiologv of Brunn ., P'"^'' ''"'T "'■' ^t "^""^'-^ "'■ J''^'" Conrad Peve. and Kiunnei Peyer was boin in Switzerland in lfi53. He studied at Sif wEn^""[' 'i^^t^^-JlS^^V".'^'^ '"^^'^-^ ^"^^•"' Schatfhaus to whS ; d^. ih I " t'" '^-- " \"'' *^" published a brochure in \M ich he de.scribed certain r^-.v glands scattered over the intestine- these glands are tam.har to every student of phvsiologv or hi'72. Sylvius, though distinguished as a physician and phvsioiogist was essentially a chemist. Through his efforts the curators of the Lniverstiy of Leyden built for him a "Laboratorium" which, so far as we know, was the first university chemical laboratorv. He devoted a large part of his time to a study of salts, which he learned to rec- ognize as resulting from the union of acids with ba.ses. Svlvius looked upon the phenomena of life from a chemical point of view. He was well versed in that p.irt of physiology derived by deductions from an- atomy and by expeiiments on animals. His opinions on the circula- tion and respiration were orthodox from our moden, viewpoint. Har- vey's teachings entered largely into his thoughts and it was chieflv through his advocacy that the doctrine of the great discoverer of the circulation of the blood became established in Holland. The contribu- tions which Sylvius made to science were essentially chemical. Hoerhaave — Herman Boerhaave. are:idv mentioned .!-■. ;• rjniti-ih- utor to the chemical knowledge of alimentation, was born in ltit]8, near Leyden, wheiv he was educated. His early years were largelv devoted to the classical an;! oriental studies. He became Ph D. in 1690, PATHFINDERS OF PHYSIOLOGY U havinp obtained the dcpree on i thesis, the subject of which was "Tiw Distinction Between Hody and Mind." An iimess in the shape of an obstinate ulcer of the ie^^ turned his attention to medicine, which he studied aldiijjr with tlie anciUary studies, chemistrv and botany. He was fc'i-aduated M. D. in IC'X], and eventually gave up the idea of the- ology for medicine. In 1701 he was appointr'd to the chair of medicine in the Lniversity of Leyden. His great ability ;is teacher caused stu- dents to flock to his lectures. His wortli was (|uicklv recogiuzed bv the authorities of the university who increased his emolument and endeavored to make his position attracti'e to prevent him from going elsewhere. Sir .Michael Foster says of him: ".Much .-duglit after as II phy.sician, acute at the bedside, biilliaiU as an expositor in the pro- lessorial chair, he was also a great teacher in the .sense that in hi.s daily intercourse with his pupils he was a!w;ps readv to lav hi-; mind open before them and to let them share his experience and hi.s thoughts. Rus.sell pays the following tribute to RcH.rhaaveV genius'- •hoerhaave was easily the most remarkable phvsician of his !nf.;„1 ?""" '''I'"' '!-^.'"" ''■'; ^•""t'^mplate his genius, his condition, the ■u P. nn/n,"' ••■ ""^ ^''^yr'-^- his unfeigned piety, his spotless char- nn Lf .• ' '""?•'■"''' ^'^ '^'^^ ""^ ™'>' "" c.ntemporarv practi.-e but nliJ "' ^^"eceedmg generations, stands forth as one ,.f the brightes names on the pages of medical history, and mav be granted a< an ex- ample not only to physicians but to mankind." Boe?ha ve "s a scholar and scientific thinker, too broad to be the slave f one idea He wa.s eclectic- in the true sense of the term, thoutrh he ne ,- • ."d himself with the medical .sect which goes bv that name He ha mind open to truth wherever it might be' sought He made use ?he oTir^'V :^^r and chemistry, but never allowed one to exclude Rn.r}..I: ''" ''''f^ -'^"bservient to the elucidation of phvsiologv. Boerhaave was not an extreme advocate of either mechanicalor the chem.ca fermentative school; he recognised that fS-'Si n Tn part a .solution of some of the constitutmts of food byme n^T of variou.s juices, which he. however, regarded not of the Sure of termen at.on He denied, however, the aciditv of the gas r". ice Colored vegetable juices were at the time coming to be u^e, as S now use htmus paper, in reaction tests. Roerhaave regarded the solution by means of juices only as part of the digestive process- the remaining process he held consisted of trituration in the stomach by which process the nutritive parts of food were expressed. His views were dominant the early part of the eighteenth century. An Epochal Year 1757— The years 1757 was the dividing line be- tween modern physiology and all that had gone before. It was the date of the publication of the first volume of Haller's Elementa Fhys- lologia. the eighth volume of whicli appeared in 1765. Albrecht vo'i Haller was born at Berne, Switzerland, in 1708. The sto-v is tolH of his early precosity, when at the age of four he is said to have "'ex- pounded the Bible to his father's servants. Before he was ten he wrote in Latin verse a satire on his tutor. Haller's attention had been directed to medicine after his father's death in 1721. while residing in the iiou.se of a physician in Biel. and in his sixteenth year he entered the University of Tubingen. Dissatisfied with his progress there he went to Leyden .where Boerhaave was at the height of his fame ' He graduated in 1727, and turned his attention to botany, publishing a 30 HALLER yoars. During iiul pliysioiojr;, . 0.^ i)f Inspiration, I importance. iJe- grcal work on ihv llura of Switzerland. Ho returi«ftl to Derno .md be gun the practice of medicine in 17l;!I. In 17;;() he wa.s api)ointed pro fe.ssor of medicine, anatomy and botany in the newly founded iiiiver sity of (Jottii.gtn, a i)osition whicii he iiad held To;- 1 , voar.s. Dii ti.i.s time he carried on or>^rinal i live.- titration in br)t;ii, . Hi.'i )-e.searche.s on the formatinn of bone, the nieehani and llie develoijnunt of tile embryo are of the hiKhi gai-dinj,' Ilaller as an expositor in physiology, l^'oster write.s: "Whv'n we turn irom the preceding writers on phy.s'ioiogv and open the pages oi Ihiiler's Elementa, we feel that wo pass into modern times. Save for the strangene.ss of mo.st of the nomenclature, and for no small ditterences in all that relates to the chemical changes of the bodv, we .seem to be reading a modern text-book of the most exhaustive kind." His chief service, however, was tlie c ful arr;\nging and digesting of the theories and facts of physiology u,) to this lime. I-'rom his lime pliysioiogy became an independent l)-aneh of science, to i)e pursued tor itself rather than as an adjunct to medicine. Keganiing Haller's method of exposition, thi' same writer goes on to sav that "In dealing with each subdivision of jiliysiology, Haller carefullv describes the anatomual basis including tlie data of minute structure, phvsical J. :oi)erties and chemical composition, so far as these were then known. He then states the observations that have been made, and iii respect to each question, as it arises, explains the several views which have been put forward, giving minute and ful! references to ail the authors (luoled, and he (inallv delivers a reasoned critical judg- ment expounding the conclusions which may be arrived at, but not o:7iitting to state ])lainly when necessary the limil;>,ti(tns which the lack of ade(|uate evidence places on forming a decided judgment. He carefully recounts and as carefully criticizes all the knowledt^e that can be gleaned about ;iny (picstion. If he feels unable to come to a decided conclusion hi' candidly says so." But we are most concerned at present with what Haller has to say on digestion. He considered saliva neutral in reaction and pos- sessing no digestive properties further than the softening of food as an aid to deglutition. H(> recogni/.ed the importance of the glandular coat of the stomach, which glands he conclud«>d furnished mucous only, the true gastric juice being derived from the arteries. He also concluded that pure gastric juice was neither ^>.cid nor alkaline and ret used to regard it as some of his pred.'cessors had done, as a fer- ment. The acidity he considered a token of the degeneration of the digesteil food. Trituration he regards as a u.seful aid to dio-estion es- pecially where hard grains form part of the food as in birds; but it was only an aid. File, he claimed, was not a mere excrement; it was secreted by the liver and stored for a time in the gall ' ladder, where it underwent .slight change. Bile is a viscid fluid, bitter hut neithi'r acid nor alka- line. It has the power of dissolving fats, and so acts on a mixture of oil and water as to form an emulsion. Haller considered the im- portr.nce of the pancreas due to the fa.ct that its ducts opened into the intr-;!ine in commnn with the bile duct; that its fluid .softened and diluted the bile, thus enabling it to mix more satisfactorlv with th^ food. He concluded by prophesying that there may be other func- tions of pancreatic juice not well known to the physiologists of his dav. PATHFINDICas OF ril\ SIOI.OCl'V II Reaumur and His Methods. Rone Atitnino IVichault do Roaumiir, a Fri'iu liin.in Ixnn in K'l^.i, arul doscriliod as one of the most notal)K' men of science of tlie ei^litei^nth century, is, in clironol()Ki<'al se- (luence next most important eontril>utoi' to the iilivsio'.o;,'^' of tlie alimentary tract. His name is already familiar to mcjst of us as the inventor of the Reaumur thermometer. His studies on the gastric juice at this time are all important, inasmuch as his methods are uni(iue. Reaumur had in his possession a kite and took advantage of the hal)it of the bird of ejectinj,' from its stomach things swallowed which it could not digest. The kite was fed pieces of meat secured in metal tubes. It was found that meat when ejected had no odor of putrilication. Kxperiments were made with small pieces of bone, which were completely dissolved when ejected and swallowed by the kite several times. On vegetable grains and Hour, the lluid of the kite's stomach had apparently little elfect. The tubes were tilled with small pieces of sponge, which, when ejected, were si|ueezed out, thus enabling the investigator to procure pure gastric juice and to study it in vitro. He proved that digestion was not putrilaction but some- thing really opposed to that process. While Reaumur's experiments left much to be ascertained about gastric digestion, he at least favored the solvent power of the succus gatricus, by the employment of a wholly new method. Experiments with Ga.stric .Juice. We must look to Italy for the next contributor to our knowledge of digestion. Parenthetically, it is of interest to note that the idea of specializing, if it had taken root at all at this early time, was not markedly apparent. The worker in the physiology of digestion was equally prominent in almost every other dei)artment of physiological research. Lazzaro Spallanzani (17:29-17!)!)) was one of the most eminent men of his time. Educated for the church, he was usually known as Abbe Spallanzani. His life was devoted to experiments, researches and teaching. He was pro- fessor at Rologna, and afterwards at Pavia. We find him lirst e.x- perimenting with germ life, with results that disprove the doctrine of spontaneous generation. His researches in other fields showed thai he had conceived the truly scientific method. Spallanzani took up Reaumur's methods and most of his results wore achieved by them. Aided by improvements in chemistry, he was able to make marked advance over his predecessors. His ex- pt iments were made on all kinds of animals, fishes, frogs, serpents, birds, sheep oxen, horses, cats and dogs, and lastly upon himself. Be- sides hollow tubes, he used hollow spheres, freely perforated, into which were placed meat and bread, bone or grains of wheat, and the results of digestion were studied when these were ejected or procured by opening the animal's stomach. He also attached pieces of meat to threads, which he would draw from the animal's stomach at fixed in- tervals. He experimented upon himself by swallowing iinen bags con- taining bread, meat and similar articles, examining the contents after they had been voided per anum. He procured gastric juice from himself by producing vomiting on an empty stomach. He repeatedly tested the action of gastric juice in vitro, keeping the tubes a uniform temperature by retaining them in his ;,.m pit, using the .same food covered by water as a control. He found that gastric juice acted more readily upon finely divided parts of food such as crii-.hed grain IS SPAI.LANZANI or bono which proved trituration only a preparation for soliitioa, and that it was no further a part of the digestive pi-oces.s. He found that the gastric juice dissolved the food of animals into a pnllaceous mass or chyme. He observed that heat favored solution and that in warm-blooded animals certain hi^'h ti'mperature was necessary for the chymilication of foods, in Spallanzani's time putri faction was considered a form of ft rmentation. "There are three kinds of fermentation, the vinous, the acetous, and the putrid." The action of Kastric Juice was not jiutrid; in fact, it tended to arrest put- refaction. Spallanzani was inclined to believe that the .iction of the frastric juice was neither vinous nor acetous. RijjrardinK the reaction of gastric juice his conclusion was that it was neutral. He believed that the acidity was due to an abnormality of the stomach contents, inasmuch as the regurgitation of sour material from the stomach oc- curred only when something had gone wrong. Spallan/.ani's failure to recognize the acidity of the gastric juice limited his further investiga- tions. He could only conclude that the action of the gastric juice wa.« not fermentation, as fermentation was understood at the time. It is interesting to note that the results of Reaumur and Spallan- zani were confirmed by Stevens of Edinburgh, who likewise employed Reaumur's methods of investigation. Stevens experimented oii a "man of weak understanding who gained a miserable livelihood by swallowing stones for the amusement of the common people." The man was made to swallow perforated silver spheres containing animal and vegetable food, raw and cooked, which were examined when void- ed some 48 hours later. Similar experiments were made on dogs, the content.s of the hollow spheres examined after opening the animal's .stomach. Stevens concluded that digestion is not the effect of heat, trituration, putrification or fermentation alone, but of a powerful sol- vent secreted by the glandular coat of the stomach. Summary: Summing up the progress made in the physiology of digestion during the seventeenth and eighteenth centuries, probably no one is more entitled to an audience than Sir Michael Foster; "Dur- ing the two centuries the seventeenth and the eighteenth, physiologi- cal inquiries, swayed now in one direction by views of chemical fer- mentation or etferve.scence, now in another direction by views of mechanical trituration, had come in the end to the conclusion that digestion was in the main a process of solution of a peculiar charac- ter, begun and chiefly carried out in the stomach, though assi.sted by minor subsequent changes taking place along the intestines. They who were under the influence of vitalistic doctrines, and these were I)erhaps the more numerous, held the change to be the commencement of, to be the first step in the conversion of food into living flesh and blood, and spoke of it as a change differing from ordinary chemical change, without being able to define the exact characters. It was left to the nineteenth century to throw new light on the nature of the gastric changes and at the same time to show that what took place in the stomach was not the whole digestion, but only the first of a Kf*T'iPH fif T'iT'f i ff';! inrl i'VinniTPJ^ t.Mlrd assures us that he was of the faith of his parents, Congregntionalist. his biocranhi-r assert. s th.it. v. Hon the mil of the drum announced the approaching hour of worship he was among those who slowly wended tl: ir way over the hills on foot or on •ll.lliliiirtnii ..; HainlhiM.k nf IMiysiul <.i; '■ Practice. Tii^^'Pstf'i.U's rii>'.sioiogy ; Osler'!^ u REAl'MONT horseback to the old meeting house. Beaumont was blessed with such rigorous parental discipline in youth that he explained his lapses in church attendance in after life by the statement that during his youth he had made up for a lifetime of church attendance. Further than that he was a courageous and fearless boy, litlle is known of his early life. It is said !hat he develoj)ed deafness, which became more marked as he gvvw older, from standing near a cannon which was beuig fired, simply to outwit playmates of his own age. The beginning of last century found Heaumont a bov of fifteen years. It was twenty-four years since (he first birthday of' the Ameri- can Nation. P.caumonfs youth was contemporaneous with one of the m()st stirring epochs in world history. The Inited States was begin- ning to a-sume an important place among the nations of the world. I.eaumont leit home during the winter of 18()G-7 with, we are told, an outtit consisting of a horse and cutter, a barrel of cider, and a hundred dollars ot hard earned money. He traveled Northward, reaching in the spring of 1807 the little village of Champlain. New York. He was very favorably impres.sed with his surroundings and with the peonle, who were mostly farmers, and whom he characterized as "[leaceful and industrious in general." Here he e-tablished his "Lares and Penates" and followed the career of schoolmaster. Coming from one of the best New England schools his services were much in demand. \Miile teaching school and during the vacation he found tir.i' to de- vote to medical studies. He had supplieil himself v.ith book-, borrowed from Dr. Pomeroy of Burlington, Vt., which town was on his itinerary to Champlain. Beaumont, as many since his day have done, made teaching a stepping stone to the profession of medicine, and an excel- lent experience it is for the aspiring savant. In 1810 he wa- apprentic- ed to Dr. Chandler of St. Albans. Vt. He seems to have exhibited a wise choice in the matter of preceptor. "Living under the same roof." writes Dr. Myer, describing the medical education of the times, "as was customary in the days of medical apprenticeship, the preceptor could , .ok after both the mind and morals of his pupils. The fledgeling in .eturn for the instruction received at the hands of his master, not only compensated iiim for his trouble, but performed many of the menial offices of a servant about the house and office. It was he who prepared the powders, mixed the concoctions, made pills, swept the office, kept the bottles clean, a.ssi-ted in operations and often through main force supplied the place of the anaesthetic of today, in the amputation of limbs and other surgical procedures. He rode about with the doctor from house to house, profiting by his per- sonal experience and .jotting down on the pages of his note book and on the tablets of his memory the words of wisdom that fell from his mas- ter's lips. * * * He was taught the symptoms of dise.ise, the crude method- of diagnosis, the art of prescription writing and the process of cupping and bleeding, considered .so effective in its day."* Medical books were rare and expensive, and fortunate was the student who had access to them. Dissections were rarely performed, owing largely to the fact of inadequate means of preserving cadavers. Such Were young Beaumont's opDortunities. Beaumont spent the two years of his apprenticeship with dili- gence, studyir.g the masters. He dis.^ected whenever an opportunity •Life and letters of Dr. Vlliam Boaumoiit. by Jesse S. Myer. BEAUMONT » afTorded, and never lost an opportunity to perform post-mortems. A peru-al of his case histories shows what a careful observer he was — a qualification of the first importance in a physician. His diploma or license to practice was granted the second Tuesday of June, 1812, by the third Medical Society of the state of Vermont. It reads: By ihc Third Medical Society of the State of Vermont as by law estab- lished, William Beaumont havinR presented himself for examination on the anat- omy of the human body, and the theory and iir.i("i<'e of pliysie and surgery, and being approved by our censors, the society willinsly recommends him to the world as a judicious and safe practitioner in the different avocations of the medi- cal profession. In testimony whereof we have hereunto prefixed the signature of our president and the seal of the society at the Medical Hail in Burlington on the second Tuesday of June, A. D. 1812. CASSIUS F. PO.MEROY. Secretary. .lOH.V POMERV, Presi(l"nt Assistant Army Surgeon: In September the same year Beau- mont joined the army at Plattsbir.'sh, as assistant surpeon under Gen- eral Dearborn. His old preceptor Dr. Chandler had unsuccessfully tried to dissuade him from the army .service, advising him to settle down to private practice. Apparently there is a destiny which shapes our end-. Had he follow.-d the advice of his old master, he would in all pr.ibability have been among the thousands of s^ood men who have lived their lives through, leaving the world a little better than they found it, and passed into the silent land, pass and leave no s\ surrounded with palisades, a deep ditch and glacis. It stands immediately back of the town and has strength to withstand a siege. The Detroit postoffice, corrier of Fort and Shelby streets, stands upon the ground at one *une occupied by the above mentioned fortitication. A bronze tablet at the south entrance of the postoffice gives in brief the vicissitudes of the old fort. He speaks of crossing over to Sandwich, then a small French vil- lage. There is no mention of the route again until he reaches Fort Michiiimackinac, which is desci-ibed a- handsomely situated on the southeast side of the island of this name, on a bluif rising from 100 to 200 feet from the water, almost perpendicular in many place;-, ex- tending about h;ilf way around the island. The word "Michiiim.xcki- nac" means "turtle" from the resemblance ef Mackinac island on be- ing approached. The folknving eiUrie-^ in his diary throw considerable light on the character of the man lumself. Sept. 9, 1S20. Commenci'd a diary of conduct on Dr. Franklin's i)lan, for ob- taining moral perfection." (Uenjaniin Franklin api)ears to have been a favorite Willi Beaumont, for he elsewhere quotes him at length.) "Keading Shakespeare tcjday I judged the following extracts worthy of copying; 'Love all, trust few, do wrong to none; be able for thine enemy rather in power than use; and keep thy friend under thy life's key; be checked for silence, but more taxed for speech. "inth. Rose at six o'clock. Visited my patients in village and discliarged garrison duty before :* a. m Settled my hospital account, perused scriiitures and I'ope's Kssay on Man till evening." Beaumont's diary is an interesting narrative of the limes, written by a keen and practical observer. The Psychological Moment: Late in the spring of 1822 occurred the event which made the name of William Beaumont famous in the annals of medicine. Indians and voyageurs had returned to Mackinac with the re-ults of the winter's hunting. A strange medley of hu- manity had gathered at the Amercan Fur C')mpany's trading post. On the Gth of June a gun was accidentally discharged, its contents entering the upper abdomen of a young voyageur, leaving a cavity which would have admitted a man's fist. According to an eye-wit- ness Alexis St. Martin, for that was his narne, fell, as every one sup- posed, dead. Dr. Beaumont, surgeon of the fort, was called, and ar- rived shortly after the accident. Shot and pieces of clothing were extracted and the wound dressed. The surgeon then left with the re- in.Al.MO.NT 27 maik that tlie man could'" "ive 36 hcurs. The doctor called apain in the course of two or thrt. iiours and found the patient better than he had anticipated. The patient was rem()\-od to the fort hospital where he eventually recovered, leavinjr, however, a permanent pasti'ic fistula. Beaumont's own afcoiinl of the accident is told in the introduction to hi- work on "Experim'^nts and Observations of (lastric Juice." "Alexis St. Man in, who ;> ihe subjoct of theso exiieriment.s, was a Caiiaiiian of French drscent at the abovf nipiitioned time (1S22| about IS years of age, of good constitution, robust and healthy. He liad been engaged in the service of the American Fur ('(inipany as a voyager and was accidentally wounded by the discharge of his musket on the 6th of June; the charge, consisting of powder and duck-shot, was received in the loft side of the youth, he being at a distance of not mor" than one yard from the muzzle of the gun. The contents entered posteriorly and in an oblique direction, forward and inward, literally blowing ott integuments and muscles of the size of a man's hand, fracturing and carrying away the anter- ior liulf of the sixth rib, lacerating the lower portion of the left lung, the dia- phragm and perforating the stomach. The whole mass of materials forced from the musket, together with fragments of clothing and pieces of fractured ribs, were driven into the muscles and cavity of the chest. 1 saw him in 2.') or .30 min- utes after the accident occurred, and on examination found a portion of the lung as large as a turkey's egg protruding through the external wound, lacerated and burned; and imincdiafelv below this another protrusion which, on further ex- amination, proved to be a portion of the stomach lacerated through all its coats and pouring out the food he had taken for his breakfast tnrotiph an orilice large enough to admit the forefinger. " Beaumont's hospital and bedside notes give a complete history of the case. Being destitute and without i-.ends or relatives, Alexis St. Mar- tin became a pauper on the town of Mackinac. It was at last decided to ship him to his native town, IMonUeal, nearly one thous;in.l miles away. Beaumont, however, rescued liim from misery and inimitable death by taking him into his own family. "During this time, .says his benefactor, I nursed him, fed him, clothed hhn, lodged him and furnished him with every comfort and dressed hi- wounds daily and for the most part twice a day." It should be realized that Beau- mont endeavored to close the wound; that when all other means failed he suggested incising the edges of the wound and. "bringing them together by sutures, an operation to which the patient would not submit." Not until three years after the accident did the idea of perform- ing a number of experiments appear to occur to the mind of Beau- mont. In 1825 he began to realize the importance of this case which had fallen to his care, when it occurred to him what a great service to humanity might result from this accident. About this time Beau- mont describes the situation as follows: 'He (.St. Martin,! will drink a (luiirt of water or eat a dish of soup and then by rt'moving the dressings I fr( quently (ind the stomach inverted to the size and about the sliape of a half-blown rose, yet he complains of no pain, and It will return itself or is easily reduced by gentle pressure. When he lies on the the processes of digestion. 1 have frequently suspended flesh, raw and wasted, and other substatices into the perforation to ascertain the length of time re- M PATHFINDERS OF PHYSIO- OOY quired to digest eaci at one time used a lent of raw beef liisdau of lint to stop tlie orifice. : dh: M that In less llian five liours it ^as completely digested off as smooth and as even as If it liad been cut with a knife." Then his resolve to make u.se of tlie case as a means of study- ing ^-astric digestion takes shape as follows: "Tliis case alTords an exeelleiit opportunity for experimenting on he gastric fluid and process of digestion. It would give no pain nor cause the least un- easiiifss to extract a gill of fluid every two or threo days for it freriuently flows out spontaneuii.^lv in >-oii.-ei\aiil win'n rmi fmpioyeii lor purpo.scs oi experi- mentation. Beaumont's laboratory etpiipment consisted of a thermo- meter, a few open mouthed vials and a sand bag. His observations BEAUMONT ■» were made with a true spirit of inquiry and with no particular hypo- thesis to support Fifty-six experiments were made between Dec. (Jth, 1829, and April Dili, 18:51. Alexis, with his wife and family, were permitted to return home to Quebec on the promise to appear when again wanted. Beaumont had felt that he had accomplished about all he was able in his researches on gastric digestion, and he longed to go to Europe a year and take St. Martin with him, that the work might be pursued farther by more competent physiologic chemists. The brevity of his furlough precluded the idea of going abroad and instead he remained in Washington with Alexis where he found his surroundings very congenial. Access to the works of European physiologists in the library and recognition from many of the promi- nent men at the capital made his sojourn pleasant. Between Dec. 1st., 1832 and March 1st, 18:',;5, wo find recorded 116 experiments, some in confirmation of what had been done before. He tested the temperature of the stomach when full, when fasting, when exercising, when resting, also the length of time reciuired to digest various food substances. He also experimented to disprove the old theory of maceration or mechanical trituration. Seeks Assistance of Two leading Scientists: In 1833 Beaumont sought the assistance of two of the leading .'-•cientific men of the United States, Robley Dunglinson, professor of physiology, Univer- sity of Virginia, and Benjamin Silliman. professor of chemistry at Yale. Thanks to Beaumont's painstaking and methodical nature, the correspondence between the two and himself had been carefully pre- served, and it constitutes an excellent account of the physiology of the period. A sample of gastric juice from St. Martin's stomach was sent Dunglinson for analvsis with the request to convey to the giver the results and to refrain from publishing anything that would antici- pate the labors of Beaumont himself. He is assured that the profes- sor has but one desire in the prosecution of his profession, by teaching and practice to benefit his fellow men, which could always Le don- with due credit without forestalling his coadjutors in the held oi science, or arrogating to himself merit to which he might be bui sec- ondarily entitled. Dunglinson found the sample of gastric juice to contain "free muriatic and acetic acid and phosphates p.nd murates with bases of potassa, ''oda, magnesia and lime and animal matter soluble in cold but not in hot water." Professor Silliman, to whom a bottle of gastric juice was also submitted, suggested that a sample be .sent to Professor llerzelius, of Stockholm, Sweden, "as the man of all others best qualified to investi- gate a subject of such deep interest to mankind." Accordingly a bottle of the digestive fluid was packed for shipment. Beaumont s disappointment may be imagined when it was known that the parcel was delayed over two and a half months. This he learned about the time he was patienlly awaiting the r., suits of the Swedish professors investigations. In the meantime Beaumont had received a letter from^ Professor Silliman enclosing an abstract of a portion of a sysiem of chemistry bv Berzelius, important as presenting a clear idea of the , '..:_„ ..V ii... -..'.-. ■:r--:.-.1.-..-r-.- .-.f r\-.m^-*.'.r:v. n f tVint timf (1.S:?;^.>. The communication states, among other things, that Prout. Tiedeman and Gmelin gave the best notions on the subject of gastric juice and ex- 30 rAriicixDEns of riivsioi.ocv pliiined the contradictory statements of other authors; at one time it was said to bo very fhiid clear and neutral in reaction; then alkaline, then acid. Prout in 1824 declared the gastric juice to contain free hy(h()chIoric or muriatic acid, the result of an experiment made on the contents of the stomach of an anim.al killed socm alter eating. Gmelin and Tiedeman also establisiied the presence of ^fvc hydroch- loric acid. The fluid of the empty stomach was found to be slightly acid, sometimes neutral and the acidity was in proportion to the (luan- tity, becoming vei'y acid when food had been swallowed. According to Gmelin and Tiedeman, the salts of gastric juice were principallv .i). He ontinui'ii. however. t(> attend llu' famih's of the olficers at St. Louis, where he made his home. Owing to the distance from St. Louis of his successor, who was stationetl ten nii!( s away, he presented an account to the NVar Department for pmfessional services covering a period of a few months, which services he conceded "irregular and informal," but "correct and just." On receipt of his account the surgeon-general threatened either to ignore the bill or to deduct the amount from the salary of Beaumont's successor. The manner in which Beau- mont received the thixat showed the independent nature of the man. He declared the surgeon-gemrars view at "absurd opinion, con- tracted view, narrow-minded vindictive spirit and petty tyrannical disposition," of the "weak, waspish and wilful head of a medical de- partment," and congratulated himsflf over having the "privilege of detesting a man, the motives and the mind from which such egregius folly, parsimony and injustice could emanate and be promulgated." The Surgeon-Ceneral was, however, unyielding, and Beaumont's claims were unrecognized. Though severed from the War Department, he still had a very lucrative practice, and what is above any monetary consideration, de- voted friends, and was very happy in his domestic relations. The following pa.ragraph ([uoted in Dr. Myer's Life and Letters of Bea i- mont gi\'es a splendid estimate of his character: "Dr. lieinniiont possessed gr(>at lirnuiess ;iml dotermination of purpose'. UilTkultios winch would have distouragt-'d most nicn. ho nevor aUowed to turn liiin from his course. These lie did not attempt to evade but to mocl and overcome. He possc^ssed more than any man I ever knew, a knowledge almost intuitive of hu- man cliaracter. You might have introduced him to 20 different persons in a dii.v, all strangers to liim. and he would liave given you an accurate estimate of the chaiacler of eacli, his peculiar traits, disposition, etc. He was gifted with strong natural powers which, working upon an extensive experience in life, re- sulted in a species of natural sagacity, which I suppose was something peculiar to him not to be attained by any course of study. His temperament was ardent but never got the better of his instructed and disciplined judgment, and when- ever or however employed, he always adnpted the most judiciou.i means of ob- taining ends that were always honored. In the sick room tie was a model of patience and kindness; his intuitive perceptions guiding a pure benevolence never failed to inspire conlidence. Thus, he belonged to that class of physicians whose very presence affords nature a sensible relief." He died on April 25th, 1858. His death was considered the re- sult of injuries he received by slipping on icy steps while making a proiessiOiiai m.mi. \\ iial a salisiaciion such a iiie must be, and the resignation with which one might approach the infirmities of old age and one's final destiny. And indeed a few rr'onths befora the end he breathed forth this beautifuly symphony: sa PATHFINDERS OF FIIYSIOLOGY "Myatlt and wife, not unlike John Anderson my Jo, have climbed the hill o' life tonitlier, and mony a canty day we've had wl' ane anlther. I'.iii now we maun totter down life's ebhiiiK wane in peaceful (|uiet ease and conipii" ni c, with Just so iniicli sellishness and social syn athy aa to he salis(l"(l with "Mr-> Ives, our children and frteiids, caring Utile for t.io formalities, follies and fashions of the present a^-e. • • • Conie when it may, we only ask God's blessing on our frosted brows and hand In hand we will go to sk>ep together." DR. BEAl MOM'S BOOK. I am fdi-Uiiiate in having be fort' mo an original copy of Dr. Beau- moiU's work. Tlu' tilii' pagf bears tlio following (Inscription: "Ex- perinu'nts and Ub.servations on the Gastric Juice ami the Physiology of Digestion, bv William fkaiimont, M. D., Surgeon in the United States Army. "Plattsburg. Printed by F. P. Allen, 18;}:5." The vol- ume is dedicated to Jo.seph Lovell, M. D., Surgeon General of the United States Army. The work comprises 280 pages, 122 of which deal with "I'leiirninary Remarks on the Physiology of Digestion." The remainder deals with Experiments and Observations on the Stom- ach of Alexis St. Martin. The lirst part is divided into seven sections, as follows: 1st, Of Ailment; Section two of Hunger and Thirst; Section three of Satisfaction and Satiety; Section four of .Mastication, Insalivation and Deglutition; Section five of Digestion by Gastric Juice; Section six of the Appearance of the Villous Coat and of Motions of the Stomach; .Se- lion seven of ('hyliflc;..ion and Uses of the Bile and Pancreatic Juice. There are three illustrations, consisting of crude wood cuts of the gastric fistuke. The typograph- ical apiiearance of the work should be c )nsidsred creditable consider- ing the printing art at the time. The conclusion of the second part of the work contains 51 inferences made from the foregoing experiments and ob.scrvations. Of these I shall quote a few: That dispstion is facilitated by minuteness of division and tenderness; "f fibre and retarded by the opposite qualities. That the quantity of food generally taken is more than the wants of the system nijuire, and tliai excess, if persevered in, generally produces not only functional aberration but disease of the coats of the stomach. That bulk as well as nutriment is necessary to the articles of diet. That oily food is difficult of digestion, though it contains a large proportion of the nutrient principles That stimulating condiments are injurious to the healthy stomach. That the use of ardent spirits always produces disease of the stomach if persevered in. That the ager' of chymification is the gastric Juice, which acts as a solvent of food and alters its properties. That the action of gastric Juice is facilitated by the warmth and motions of the stomach. That it coagulates albumin and afterwards dissolves the =oa."ulum. ciples. 'iiiai iiic ga.-!iiii_ Juiee i= seuieteu from vessels disii'ici from the mucous f.dliclcs. That bile is not ordinarily found in the stomach and is not commonly necea sary for the digestion of food, but assises in the digestion of oily foods. DEAl'MONT That the Inner roat of the gtomiich Is of pale pink color, ra.Tlng In Its hues accordUiK to U» full or empty stato. That the motions of the Btoniach produce a constant churning of Its contentB and admixture of the food and gastric juice. That these motions are In two directions, transverse and longitudinal. Beaumont failed, however, to ascribe any digestive function to the saliva. Ho maintained that food finely divided placed directly into the stomach was as completely digested as that which entered by the oesophageal route. When he began his work the status of the physiology of digestion had been very well described by \\'illiam Hunter; "some physiologists will have it that the stomach is a mill; others that it is a fermenting vat; other again that it is a stew pan; but in my view of the mailer it is neither a mill, a fermenting vat nor a stew pan, but a stomach, gentlemen, a stomach." When William Beaumont com- pleted his labors there was a marked advance in knowledge of the digestive process. Among the most important results of his worlj was his complete and accurate description of the gastric juice, which has been quoted in so many text books since his day. "Pure nastric Juice when taken directly out of the stomach of a healthy adult, unmixed with any other fluid, save a portion of the mucus of the stomach with which it is most commonly, perhaps alway.s combined, is a clear, transparent fluid; inodorous; a little saltish, and perceptibly acid. Its taste, when applied to tbe tongue, Is similar to mucilaginous water, slightly acidulated with muriatic acid. It is readily diffusible in water, wine or spirits; slightly effervescent with alkalies, and is an effectual solvent of the materia allmentarla; It possesses the property of coagulating albumin in an imminent degree; it Is a powerful anti- septic, checking the putrefaction In meat; and effectually restorative of healthy action when applied to old foetid sores and foul ulcerating surfaces." His work confirmed the observation of Prout, that the acid con- tents of the gastric secretion was hydrochloric. He recognized the fact that the elements of the gastric juice and the mucus of the stom- ach were a .separate secretion. He established by direct observation the marked influence of mental states on the secretion of gastric juice and on digestion. His was the first comprehensive and thorough study of the motions of the stomach ; and to quote Osier: "His study of the digestibility of different articles of diet in the stomach remains today one of the most important contributions ever made to practical dietetics." A German edition of the work was issued in 1834. In 1838 Sir Andrew Combe, an eminent English physician, published an English edition of the work, so as to give it greater publicity in the British Isles. Probably no fairer or more impartial estimate of the value of Beaumont's contribution to science has been made than that of Sir Andrew in his preface to the British edition. Answering the objection that Beaumont had made no original discovery in the phys- ology of digestion, this advocate claims that by "separating the truth ,.1..-.i.1.. .....3 *....,.,. 11.. »—-.—. i-^-. _. __,-_ .. ..,. .. -^ J? i _ " _ — • ciCciny ciiiu uiivjciuivuctiiiy injm tuc iiuiiic-iou.^ cnuiS oi laCl- aiitl upiii- ion with which it was mixed up, and thus converting into certainties points of doctrine in regard to which positive proof were previously inaccessible, he has given to what was doubtful or imperfectly known 14 PATHFINDERS OF PHYSIOLOGY a fixf'd and positive value which it never had before, and which, being once obtained, goes far to furnish us with a clear conn< cted and con- sistent view of the general process and laws of digestion." CM-ATDK l!l-;U.\AI!l). I'llVSIOI.OClS I'. 1^!.!-1.S7K CHAPTER IV. GLYCOGENIC FUNCTION OF THE LIVER— VASOMOTOR NERVES— CLAUDE BERNARD. "For a man to bo an Invt'stlKator of the flrst order two Klfla are perequlclte It Is not merely neceBsary to imsseBs a wellordered and what we may term a philosophic ImaKinatlon, to possess a mind that Is capable of balanclnn phenomcoa. soeInK their relationship and --^i«I«P.v of respiration; crlT \ i tV^-^ contended that the function of breathing was to coo! he blood. It was noticed that animals over-heated from exertion breathed more rapidly, hence the inference. Galen (l:n-'>0-} A in d mn"'uie^'nnl,l^t!''*/^f Vu T^''"^ '"''-'^ ^^ ^^^'"'^^e and to cool che.^ !'',""!*''• ^^'^^ °f [^"^ ^^''^'•t: that the peculiar action of the nil red Vol tf" "y'''P'!:^*'°\"^troduced into the blood the air re- quiud tor the regeneration of vita spirits in the left side of fhP oi'rthetdrry'%"'^"-'^'' '■°"^>^ 'A ^-^^ df^tributed'fhrtgh! 'f''f1 ■^- *^'^'^" ,?''^° recognized the necessity of ridding the body of fulginous vapors; produced by the innate fire in the hfart which ?eitu?;-TeZ.' d^H^ by e.xpiration. In the latter part of the fifteen S dLnrov;ri thTf«i/\^ P^-'"*f' "I'-^thematicvin and naturalist, He found t^/^"^'^-'' ^^""^ ^'^ ^'?P'y <=o»led the blood in respiration He found that air was consumed by fire and that animals could nnt first "cor? inTe 'H"r"%°' '^"PP"^'^'"^' combustior ThTs" s ?h mst lecord in the history of science which pointed to the fact th ,t the tunction of air in respiration depended upon itfchemcal com- position and not upon its physical properties. cnemicai com- It is- evident that no real advance could be made in the nhvsinlocrv 4 Sl7e""L ■^',\"^:?''^^r fi^' ^'^^'^ hadti^dtfott'rS unti tv,^rvf;i clepartrnent of the science of physiology lagged unt 1 the chemist appeared on the .scene. Harvev had panted out hat as the blood went to the lungs from the right side of he hea?t thence to the left auricle a marked change took place the blood as suming a bright arterial hue. The cause which resulted in this peculiar change, Harvey was unable to d; .ern. nor d d it become known until a much later day. when scientists became familiar wUh the characteristics and constituents of atmo.spheric air. Mechanics of Respiration. The first real knowledge on the mechanics of respiration we owe to Borelli. Apnhing the knowledge of mu.scular contraction on the one hand and atmospheric pressure on the other, he taught that insni?a tion consisted of the entrance of air into the chest by virtue of at rr't'lir'nfP-r'''''n ^'^^^ ^'^^^'f-^ being enlarged by the muscular con- tiaction ot Its v. a Is; expiration consisted mainlv in a cessation of muscular contracUon. Borelli broke with the ancient view IhS the function of breathing was the cooling of the excessive heat of the hoiirt or the ventilation of the vital flame. "So great a machinery and vessels and organs of the lungs," he continues, "must have been instituted for some grand purpo.se; and that we will trv to expound il po.ssible. though we siiall st.inmer as we go alon^." ^Airain hp in! "'"V'.. ^-"■.^^'<'^'" >" '^y breathing is the chief cause of the life of ani- mal.s. It IS more important than the heart and the circulation of the blood. ROBERT nOYLB 4S The Work of IJoyle. Now we turn to the English school. Robert Doyle (1027 lODl), perhaps the most re- nowned physicist of his time, by means of the air pump made many researches on the "spring" of air. He showed, among other things that a flame wa.s extinguished in a partial vacuum and that in a more complete vacuum not only the flame but the lives of small animals such as the mouse ceased very quickly. Here we see that the phenomena connected with the burning candle closel.y re.scmbled the phenomena of life; furthermore that air what- ever it might be. and not the mechanical movements of the chest wall was necessary for the continuance of life. Boyle lived at Ox- ford for many years and while there made important improvements in the air pump and in a long series of experiments with it made vari- ous discoveries in the properties of air and the propagation of sound He was at the same time an ardent student of theology. He was ad- vised to enter the church, but declined, feeling that his writings on religious topics would have greater weight coming from a layman than from a paid clergyman. As a man of science he was the first to carry out the principles of Bacon's Novum Organum. The next step was taken by Robert Hooke, who was for some time assistant to Boyle. Hooke was born on the Isle of Wight, in 1635. He was destined for the church, but ill-health diverted his career into other channels, which gave scope for his precocious mechanical genius. His personal appearance is described as very unattractive; his hair being in dishevelled locks over his haggared countenance. He possessed an irritable temper and was much given to spending his time in solitude. To him Boyle was endebted for valuable work in connection with the perfecting of his air pump. He was one of the earliest and most zealous users of the micro.scope ; a volume entitled Micrographia. con- tains an account of his many "Ob.servations Made on Minute Bodies of varied kinds by magnifying glasses." Hooke's microscopic studies on cork lead to the adoption of the term "cell" as the histologic unit He was curator of the Royal society, at a meeting of which he demon strated before the Fellows an experiment on artificial respiration, which had been made before and many times since. The uniqueness of the experiment consisted in the important conclusions which Hooke made. The experiment consisted in opening the thorax of a dog and substituting the movements of the chest wall bv respiratory move- ments accomplished by means of hand bellows, the nozzel inserted in the trachea. This proved th t the mechanical movements of the chest wall were only of a secondary importance and that the whole business of respiration was carried on in the lungs. This fact was fur- ther proven by inflating the lungs to their utmost capacitv and keep- ing them distended by a powerful blast allowing the air lo'escape con- tinually through minute holes pricked in the lungs. This showed that life could be maintained even in the absence of the artificial move- ?I!!"u „!.^„i^!!^ r^ *^^ JP?''*^"^^-^'™^ °^ th^ '""fi^s ^^'ere so subjected ^o a i"""'' "■■^.^Vl,"* j'\' i'''^'i"i:icre me secret oi liie change from venous to arterial blood depended upon the exposure of the blood to fresh air which was in the course of life accomplished by the bellows-like action of the chest wall and diaphragm. 44 I'ATHFINDERS OF iniYSIOLOGY .p., /''•'"«* ,'"/o'o^«f ^«no"« t» Arterial Blood— Richard Lower, \ : '^•'uCluded that the change in color, venou.s to arterial, blood was due to the exposure of the blood to the air in the lungs; he drew the further conclusion that the change in color was dje not to the ex- posure alone, but to the fact that the blood took up some of the air; that is, according to Lower, arterial blood differed from venous in that it contains air. The blood gave up its "fresh air" in the course of the circulation, hence the necessity of a constant supply of fresh air for the maintenance of life. "Were it not for this, we should breathe as well in the most filthy prison as among the most delightful pastures • * * "h, fact," he continues, "where a fire burns readily there we can easily breathe." Note that there was no men- tion that only a part of the air was taken up by the blood. The com- mon knowledge of the time was that air was a simple substance, not a mixture of several elements as we know it today. Mayow and His Researches.— The next contribution to the sub- ject of respiration was that of John Mayow, bom in London in 1643. Mayow was a lawyer by profession and science was his avocation. iMany valued contributions to medical science were made by men whose lives were spent in other callings. Priestly who discovered oxygen was ji Lnitarian minister; Schleiden, whose name is con- nected \yith the cell theory, was a lawyer; Schwann was a botanist; Metchnikoff is a biologist. Thus many of the important discoveries germain to medicine were made by men whose work was inspired bv the fascination o the subject in hand-the avocation of their leisure moments. Of Mayow it was said he took his degree in law and became noted lor his practice therein." Mayow's published works consisted of four tracts— de .sal nitro et spiritu nitro aero; de respi- ratione; de respiratione feotus in utero et ovo; de motu musculari et spintibus animahbus. He showed that it was not the whole air which was necessary for respiration, but onlv a portion, and that par- ticular constituent of the air which has since become known as oxy- gen In the language of the chemists of his time, for he was essen- tially a chemist, Mayow endeavors to prove "that this air which sur- rounds us, and which, since by its tenuity it escapes the sharpness of our eyes, seems to those who think about it to be an empty space i-s impregnated with a certain universal salt, of a nitro-saline nature' that IS to .say, with a vital, fiery, and in the highest degree fermen- tative .spirit. The word ".salt" was used by the seventeenth centurv chemist to designate any substance not distinctly metallic or liquid. Mayow sums up the conditions necessarv for combustion- "con- cerning fire It must be noted that for the ignition of this it is neces- .sary that igneo aereal (evidently oxygen) particles should either pre- exist in the thmg to be burnt or should be supplied from the air (.unpowiler IS very easily burnt by itself by reason of the igneo-aereai particles existing in it. Vegetables are burnt partlv bv meins of the igneo-aereal particles existing in them, partlv bv 'help of .nose brought to them from the air." This early chemist recognized the fact that in combustion we have a chemical combination with the substance burnt, and as a result an ;ictii;.l inn-^.,... ;„ „.„:„i,* t, experiments with antimony, which he burns bv focusing the "sun's rays by mean.s of a lens; by weighing the substance he finds an in crease in weight which he attributes the "insertion into it of igneo- MAYOW acreal particles during the calcination. As we shall see more than a century later Lavoisier arrives at the same conclusion. But Mayow did not stop here. He proceeded to point out the identity of burning and breathing: ■If a BiiiiUl animal and a liKhted candle be shut up in the same vessel, the entrance into which, of air from without is prevented, you will see in a short time, the candle go out; nor will the animal long survive its funeral torch. Indeed, 1 have found by observation that an animal shut up in a flask together with a candle will continue to breathe for not much more than half the time than It otherwise would, that is without the candle. « » • The reason why the animal can live some time after the candle Ims .;one out seems to be as follows; The flame of the candle needs for its maintenance a continuoua and at the same time a sufficiently full and rapid stream of nitro-aereal particles. Whence it comes about that if the succession of nltro-aereai particles be iiitrrrupted, cvt n for a moment, or If these are not supplied in adequate quantity, the flame pres- ently sinks and goes out. Hence, so soon as the igneo-aereal particles bi'gin to reach the flame scantily and slowly, it is soon extinguished. For animals, on the other hand, a lesser store of the aereal food is sufllcient, and one supplied at Intervals, so that the animal can be sustained by aereal particles remaining after the candle has gone out. Hence it may be remarked that the movements of ilie collapsed lungs not a little help towards the sucking of the aereal particles which may remain in the said flask, and towards transferring them into the blood of the breathing animal. Whence it comes about that the animal does not perish until just before the aereal particles are wholly exhausted. * ♦ • We may infer that animals and fire deprive the air of particles of the same kind." Mayow's account of the mechanics of respiration would need lit- tle or no revision for a modem text book on physiology. He showed that the air entered the lungs during respiration solely by atmospheric pressure. He makes use of the experiment whereby a collapsed bladder is placed into a bell-jar, the bladder expanding as the air in the Jar is exhausted by means of an air pump. He taught that in in- spiration the chest is enlarged by the descent and contraction of the diaphragm and by the raising of the ribs. Mayow further tackles the raison d'etre of breathing in which he shows that something necessary to sustain life passes from the air into the blou.l. "We have no right," said he, "to deny the entrance of air into the blood because on account of the bluntness of our .senses we cannot actually see the vessels by which it makes its entrance." These extracts go to show how mature the views of the seven- teenth century school of English physiologists, Boyle, Hooke, Lower and Mayow in particular, were. Mayow by his nitro-aereal or igneo- aereal substance evidently meant oxygen. Their work was, however, allowed to slumber, until the scientific path was retraveled by their successors nearly a century later. Summary I'rior to the Beginning of the Eighteenth Century.— Van Helmont (1G48) had discovered some of the properties of car- bondioxide. He showed that i gas was formed from fermentation or the combustion of carbon and from the action of vinegar on cer- tain carbonates, and that this gas was incapable of supporting com- &u.-5iiuii. iju,\ ie (iu(U^, a.■^ ue iiave seen, proved tiiac air was neces- sary to the life of all animals, even those which lived under water. Bernoulli, at a later date, showed that the existence of aquatic ani- male depended upon air held in solution in water. Hooke exposed 1« I'ATIIFINDKRS OF I'll YSIOLOCY tho lun^rs of a livinjf animal and maintained the vital processes bv pe hM upon a eontinuai cha.iKo of air ... the lu.igs. Fracassat dr' w .''-■';.'>. to the (act that the red color of 11,. upper surface fa d.U > as due to its exposure to air. Mayow (Kwl) advance.i the vk'w Sich"".r'H'"r' " f""""'"'*^' '="^''''^'^" "'■ •'^"PP'"ti"*r combustion, and ^h ch. absorbed m respiration, ehaUKcd venous into arteral blood •md uas the eaus.- ot heat developed in animal bodies turv^tSitSor^"?^"'-'' '^•»">«'--Amon», the early eighteenth cen- u \ tuntiibu oKs to our kn(.wk..iKe of respiration was Stephen lies born l(,u who, oy the way, was not connected with the med- Ln r'\"-T'""V "'-'.'•^'c^'ived his AI. A. degree at Cambridge in U03 ' caS'thieh h"'V"7 '".^^'V-, l^!-' ^-'^'^ ^ clergyman by proPess on .1 calling which he followed until his death in 17G1. He is chieflv known as he inventor of a "ventilator," by means of which frtih air wa« mtroduced into jails, mines, hospitals, an,l shp.V holds Four .ears after the mtroduction of Hales' inven ion mtoThe Savoy prison only four prisoners died, whereas the mortality before its ntroduc tion had been as high as one hundred a year. Devoted as was H lU s o the church he was even more devoted to scienct^ He wa^the first to determine blood pressure by actual experiment on the livfng animal iNext in chronological .sequence is Joseph Black, an eminent chem ^^Zf Bonkaux in 1728, where his father was en?aS in t?e wine trade Both parents were of Scotch descent. In 174tf Black en r ciSen^^H^f '■ "' '""^^«?' '''^''' ^^' '^^udied chemist^ under urt/in i?^.i i' however, graduated from the University of Edin- i M?aSd Ihe .iliali .^i'■''1"''H''^!,'^'-'^'■' ^' P''^^-'^^' ^'^='t the causticUy of mlf th'i,^l^^a'i« 1'^ due to the absence of carbonic acid present -n term "xed ur ••'^ T? T '^' '''"" carbondioxide but instftuted f^'e 71? AL'' 1 ^"™'^'^ "''"'^ ^■^'■^ "'■■'^t used by Lavoisier in -48. L ack s work was a distinct contribution to chemistry In 1 o.. he became professor of anatomy and chemistry at Gksgow bu shortly become professor of the Institutes of Medicine^ In he me^m- tmie he practised his profession an.i found opportunitv fo or?^^nal Edh;tf->!°"Hi'", 'J'' ""' ^^"-^ transferred tl\ s^miUr posS fn h-dinbui^h. His lectures were noted for their clearness and wh-it i, perhaps the best testimonial to any lecturer, his c a 'ses Came the largest and best attended in the universitv. Though of delicarecoi st^Uution, by constant care he lived to the^ fairly ripe age of Teven??: Black had been anticipated in his discovery of "fixed air" bv Van UnlT'l' "^'T '•^^^■'''■^■^■^'■^ had been made a century earlier In other words, he had re-discoN red the gas later to be known as' CoIr. usmg clear lime water, he was able to show th'it "fiv H .i •- • ^ •>'r in lermentation. in expiration and thTt t as a 'product o? gurn" .ng charcoal. The chemical formula for clear lime 4fer ifca (OH) ' at Am ''" r^:'"''' ^' •'■^'■^^■^ ^'"■'" CO^. becomes Calcium Carbon ' tLS Slv.^'^l''^ •" r'^'P'^''^'^^' ^'^ '^halk. and water (H?0) The fnt nffl '^'""?' 7^'^'"" '■'' °^ ^""^^'^' ^ reduction in the caus! ticity of the original substance. taus- i ciuGte the fuikminj^ extracts from his treati.se on chemistry •■I had discovered that this particular kind of air, attracted by alkaline .ub- :nances, is deadly to all animals that breathed it by the mouth and nostrils t' IMUKSTLY 47 gtthJ-r, bur ir 111.. ii.iHlillH wtT." kept Klnit I nvuh IcI to believe Unit It mitiht be broatlud in »afij|y I fouiid for example that when Hparrowo died In It In ten or eleven seronds, they vsoiild live In 11 thr ,r tour nunuteH when the noHtrlls v\ere Bhut by melted ault. And I eonvlneed myself that the chauge produced on VNholrsome air 1)y breathing It conHlsted chiefly, if not wholly, In tho conversion of imii of it into llxed air. For 1 found, that by blowlnx through a pipe inf.) lime water, llie lime \v,ik precipitated, and the alkali wag rendered mild. • • • In the same year I found that llxed air is the chief pan of the olaHt!.< matter. wln(h Is formeil In ll(|iild» in the vinous fermentation. Van llelmont has Indeed •aid this, l.ut it was at random that he said it was the same with the (iroito del Cane In Italy (but he supposed the Identity because both are deadly), for he liati examined neither of them chemically, nor did he know that It was the air dlfi- enganed In the efferves.ence of alkaline sub.stames with ae hul iiiie onhouox sinners, such a number ot friends to excuse or justify them. Do not, however, mistake me. It is not to my good friend's heresy that I impute his honesty. On the contrary Us his honesty that has brought upon him the character ot heretic." i 41 PATIII'ISHKliS OK PHY.SI0I.OfiY Priestly was thirty years old when i'ranklin wa.s .sixty. Priestly iiiwell duhhed him a "literary Jack-ot' all-trades," and he was busy with proof sluets until the day of his death His paniiilikts (in politics and religion were so much opposed by the orth jdiix the (iloKiaiis (if his day that they answered his arguments by buininK his house and dispoilinj,' his beloiiKiiiKs, a peculiar wav that the so called orthodo.x theoluKy has had in the past of dealing' wih tho.se bold intrepid spirits who have dared to stand for what they believed to be the truth. His home surroutidinKs in I!irmin>rham became so unpleasant that in self-defense he ;et sail for America, here to breathe the atmosphere of civil and reli^rious freedom. He was offered the [.rofessorship of chemistry in the I'niversitv of Phila- delphia, but the followinj,' year moved to Northumberland, a town on the .Sus(iuehanna, a hundred and thirty miles northwest of Philadcl- I)hia. He lived and worked until his death, which occurred in Feb- ruary, 1804. Priestly endeavored t-- changt back to its original condition, air that iiad been breathed, or which had failed to support the flame of a candle. He eventually succeeded l)y means of vegetation. First he exiH-riD >nted b • placing a sprig of mint into a glass jar standing in- verted over a vessel of wate Parenthetically. Priestlv invented the pneumatic trough, which has been found so convenient in experiment- ing with gases. When the sprig of mint had been growing some mont.'i-^. the air within the vessel would not extinguish a flame nor act deleteriously to small animals, such as the mouse, placed therein 1 he growing plant -eally contributed to the flame or the animal that was placed in the vessel. Further experiment showed that a growing plant placed in a vessel in which a flame had been extinguished would m time r. n icr the atmosphere in the jar capable of supporting either flame or animal life. This lead him to conclude: "That plants, in- .stead of affecting the air in the .same manner with animal respiration, reverse the effects of breathing and tend to keep the atmosphere swef^t and wholesome when it is become noxious in consequence of animals either living and breathing or dying and putrifying in it." Priest ly'.s researches might have been more fruitful in re.sults had he not been dominated by the phlogiston theorv, a term devised by .Stuhl. Phlogiston, from phlogistos, burnt, was a hvpothetical principle of fire regarded as a material substance. Every combustible substance was a compound of phlogiston and the phenomenon cf com- bustion was due to a separaiion of the compound into its component elements. Priestly was able to obtain the same gas bv heating mercuric oxide, and from red precipitate. Rut he could not get away from the phlogiston theory. Air .supported combustion because it took up phlogiston given out by the burning body. Common air supported combustion in proportion as it was free from phlogiston. He pre- pared ox.Vgen in 1774. that is he di.scovered that the s-nf. ho nron.ired was part of the common air, which supported life and combustion! Venous blood was blood laden with phlogiston. Blood expos^>d to de- phlogisted air gave up its phlogiston and became bright arterial blood. LAVOISIER 4» Some idea of the scope of Priestley's researches may be inferred from the mere cataiotfue of his discoveries. He is credited with dis- covennsr dephloKisticatod air (oxyjjren) hydrochloric acid, sulphur dioxide, nitrosulphuric acid, sulphuretted hydrogen, and the solation of amonia g&a. Lavoisier and HLs Work — Antoine Laurent Lavoi ,ier was born m I aris in 1712. trn years later than the date on which Priest Iv first saw the hjfht of day. As scientist his career was practically uintem- poran.'ous with that of Priestly, who made the same momentous di.scovery working mdependently. In 1775. a year after Priestly i ad prepared his dephloKisticated air (oxygen). Lavoisier published rs paper On the nature and principle which combines with metals dur- ing their calcination." In this paper he showed that metals on lK-i:,tr burnt did not give up phlogiston to the air but took something from tne air; they on becr)ming metallic oxides, increased in weight La- voKsier dealt the death blow to the phlogiston theory and was in a sen.se t he real discover of oxygen He proved that the" principle which combined with metais when - 'cined was the principle of acidity He say.s: '1 shall therefore designate dephlogisticated air, air eminently respirable, when in a state of combination or fixedness by the name of acidif.\-ing principle, or. if one prefers the .same meaning in a Greek dress, by that of 'oxygme' principle." Lavoisier discovered oxygen and gave it the name by which it will henceforth be known He made further experiments in connection with respiration which he con- cluded to be a combustion, slow it is true, but otherwise perfectly similar to the combus,tion of charcoal." He eventually saw. however of carb(!Jl*^d?o.xSl ^^''^^^^ '"spired had other use than the production ,.pnt,!rwvf r.l; ^«^^^T/ ""ti! the early decades of the nineteenth century that the view that oxidation took place in the lungs gave way to the accurate theory of tissue respiration. In 1837 Gu-'ave Magnus proved that both venous and arterial blood contained oxygen and cprbon dioxid. -^j^k^" Hydrogen was discovered by Cavendish in 1781, when he also discov-ered the composition of water. Nitrogen was discovered in 17/2 by Rutherford, Oxygen was prepared by Priestly in 1771 and recogniz.d by Lavoisier the following year. Carbonic acid gas or car- bon dioxide was first discovered by Van Helmont in 1610 and redis- covered and defined by Black in 1757 niAI'TKIi VI. THE NERVOUS SYSTEM. The pro^jrcs.s of knouiedgo of the nervous system has been ver: slow. Most of the other viscera were known to the ancients before the brain was recognized. The word "brain" is not to be found in the Bible. The ancient Hebrews evidently looked upon tlie heart as the seat of the soul. The kidneys were the habitation of the mind, while the tender emotions were referred to the bowels. Plato was perhaps the first to assign the supreme seat of the mind to t'^e brain, but his view.-, were purely speculative, inasmuch as he confounded the sub- stance of the brain and of the spinal cord with the marrow of bones. Aristotle, about 335 B. C, examined the brain for himself and con- cluded that its function had nothing whatever to do with the mind, but that it was a refrigerating organ which cooled the blood for the heart. He reasoned according to the knowledge of his time. The brain was apparently an insensible and inexcitable organ as contrast- ed with the heart, which is the opposite. Hippocrates recognized how soon animals became unconscious from the loss of blood, or how clianged by blood poison or by the heated blood of fever- hence the inferenca by Ari.-.totle that the conscious mind resided . he blood and that the great central organ, the hf^art, was the .seat ui the soul. The arteries (f. jm the etymology, air tubes or wind pipes) found empty after death, were supposed to carry air or "ethereal" spirits to the rest of the body. It was this great blunder that delayed for cen- turies, virtually until Harvey's time, all progress of knowledge of the true function of the heart. Hippocrates maintained that the brain was a gland. With this supposition subsequent writers ventured the suggestion that ♦he brain secretion was a subtile fluid which they designated "animal spirits." The authority of such names as Hip- pocrates and AristotI.> forbade first hand investigation for fully five centuries. It must i >t be overlooked, however, that amid all this gruessing, Alcmaeon (about 500 B. C), an anatomist and physiologist, taught that the brain was the seat of the mind and that all sensation traveled to the brain by means of the nerves. He spoke of the nerves as "tendons" which misconception held sway until Descartes, the philosopher, showed the difference between tendons and nerves. About 300 B. C. sprung up the Alexandrian school of anatomists and physiologists of whom Herophilus and Erastistratus were chief who dissected the brain and traced to it the nerves as Alcmaeon had done. They even went so far as to distinguish nerves of sensation and nerves of motion, but were still hampered by Alcmaeon's "ten- dons. "When Greece fell under the subjection of Alexander, mind wen*- into exile, and its first asylum was the city of the conqueror." Under royal patronage the study of anatomy and physiology and surgery made great progress, '".alen spoke of Herophilus and Erastistratus as possessing more accuiate knowledge of the human body than any one before their time. He**onb.iln.^. v-*n5^ fht^ nr^^.f f^nntrimis:^ nf :rv*.rt.".rfsr'.."ri in the annals of medicine. He is said to have discovered the lacteal THOMAS WILLIS 61 vessels, and the construction of the eye. including the retina. Galen speaks of Herophilus as having a very intimate knowledge of the anatomy of the nervous system. The term, "torcular Herophili" signifies the "press" or dilation at the junction of the superior longi- tudinal lateral and occipital sinuses first described bv Herophilus. Herophilus and his associates performed vivisection upon condemned criminals. Not only did medicine progress during this early period (about 300 B. C). but literature, philosophy, mathematics^ natural history and astronomy flourished as well under the patronage of F'tolemy. A great part of the record of this fruitful period was lost during the seventh century of the Christian Era. with the destruction of the great Alexandrian library. i^n "^*"' J^*"'"" ^^^ ^^'^^ <**" Thought and Sensation:" Galen. A. D. IbO. overthrew Aristoile's theory in re.'' _1" '•^■"-'-■"•^' ^""-' iuiiciion or Cue opinai ucrxea, and accord- mg to Gorton, contributed more co the knowledge oi the nervous system than any of his distintuished predecessors. Magendie was ■'* PATHFINDERS OF PHYSIOLOGY bom at Bordeaux, France, in 1783. studied medicine in Paris, where he became demonstrator, and eventually professor of anatomy in the College of France. He died in lg"i5. Magendie is described as being abrupt in manner, even to rude- ness. His brusque manner has been i ferred to in his relations with hi.s understudy, Claude Eeniard. He seems, however, to have been a brilluint if not very methodical worker. He refers to himself as a njgpicker by the dust heap of science. His work on the nervous system was parallel with that of Sir Charles Bell, and the scope of the work of both is epitomized in the well-known Bell and Magendie l.aw to the effect that the spinal roots may be divided into afferent and etterent, the anterior roots carrying impulses only from the spinal cord to the periphery, while the po.sterior roots cairv impulses from the periphery to the central nervous svstem; a nerve fibre can- not be both motor and sensory ; we may have both ner\-e fibres in a single ne.Te trunk but the fibres in each case are isolated and con- duct impulses only in one or other direction. To Claude Bernard, associated with Magendie in the College of trance, we owe the discovery of the vaso-motor nerves. n^.f^p"*""* u"** ^^"^ "^^^'^ Center."_In 1861 Pau] Broca, an immi- nent French surgeon, proved that there is a -lefinite locality in the "Rrn J r^ " ^' ■''"* f ^'•ticulate speech. This is known todav a, Broca s Convolution." Nine years later, thanks to the labors of such men as HitzigJ^>rrier and Charcot, it was shown that each of the special sense.s has its anatomical seat in the brain. It was also found ract bv tbTlvllt'V-"'"' '■ "'.^-""VP «f ^^^'^-'^ ^""'^' be made to con tract bv the excitation of certain "centers" or localities in the surface a' s •'!?'"• wnH^h^'^rf 'f '"'■ ""''^r'' •" ^^'-^i" physiology. Gorton .>a.,s It IS worth while to note the stride anatomv has made dur- ing the closing years of the nineteenth centurv, especiallv in knowl- edge of the central nervous system of man and animals. Ea^v in the las decade of the century the subject was taken up by German and ittrs '"t T'S'- ^^'^-y^'-- ^^f' ^Marchi. Golgi, His, Apath^ and others To \\ aldeyer we are indebted i<,r the doctrine of neuron as applied to nerve cells, from the Greek word "neuron ' signifying unft according to this doctrine every cell is a unit having an independent txistence, distinct and apart from other cells, though related to tium an may degenerate and die without affecting the existence of the o ners. Meynart estimates that "the cortex of the cerebral hemis- pheres alone contains twelve hundred millions of ganglionic cells'-" and Donaldson states that three thousand millio,- cells "is a modest "'^r''^f. lu^;*^^'''' """^b'^'' «f these neurons in th, central nervous .system. The doctrine of neurons has been assailed a> aFrolied to oom- Kr^hv P Jr' ■ -f \^l di^^nPui'^hed Apathy, and defended among others b.\ Barker, of Johns Hopkins I'niversitv." The invention of ti.IIues^ PJ-oces.H-s afforded a powerful impetus to the study of nerve By means of animal experimentation Flourens. Luciani and Horsley determined the fijnptinn ^f ti.„ „ov.m „ n.. ,"„',." cerebrum from a frog or pigeon caused all its voluntary" movements to cease, but did not intert .- with the reflexes or the negrtTve func PATHOLOGIC STATES OF THE BRAIN 66 tions. The same investigators found that if the cerebrum was re- moved and the cerebellum left, the animal has sense of appreciation but fails m muscular coordination. Stephen Hales showed that the spmal cord is necessary for reflex movements and Marshall Hall work- ed out the whole problem of reflexes. Galvani (1791) studied reflexes by applying electric stimuli to frogs' legs. Pathologic States of Brain and Nervous System— Apropos of the development ot knowledge of the physiology of the nervous system is the evolution of our knowledge of its pathologic states. The insane nave suffered much owing to ignorance and misconception on the part of the .sane. Ancient nations lookod upon the insane as possess- ed of evil spirits or as "possessed of devils." Later the Cxreek Alex- andrian, and the Roman, looked upon the in.sane man as a sick man and he was accordingly treated by means of drugs, baths, exercise and other hygienic measures. A great retrogression took place during the second or third centuries of the Christian era. Theories of demoniac possession again he d sway, with the result that the insane were sub- M I.'. A ^"^ "^'"°^* *'''"'^'*^- '^^'•^ attitude continued throughout the Middle Ages. In fact, no marked advance was made until the eigh- teenth century. Various places of custody were maintained for the msane where they were confined in dungeons, badly clothed and bad- ly fed. The first real advances in their care were made by Philip Pinel, in France. Tuke. in England, and Benjamin Rush, of America near the ..'nd <.f the eighteenth century. Pinel in 1793 substituted a system of non-restraint and humane treatment for blows and punish- ments. \\ ilham Tuke, member of the Society of Friends, Wcts mak- ing similar reforms in England. Stahl, early in the eighteenth cen- tury, insisted on the essentially sinful character of insanitv and this attitude found echo in Heinroth in the early nineteenth centurv Religious theorie.s have little by little given place to physiological and psychological explanations until today the insane man is regarded as a sick man. Insanity implies disease organic or functional, just as do other abnormal manifestations, ...r .''h;'da,'/;,"fMre'1asr'paV°afraf'„ ''""""■'' ''"''' °" ^''"''' diseases, 19U, CHAPTER VII THE CELL THEORY "The cell theory furnishes the starting point for all modem studies in biology and enables all students to speak the same language." says a twentieth century writer. The recognition of the fact that animals and plants are constructed on a similar plan must be placed among the most important discoveries of the nineteenth century prolific as that century has been in scienuific achievement. "No other biological generalization," says Professor Wilson, referring to the cell theory, "save only the theory of or- ganic evolution has brought so many diverse phenomena under a J^cmmon point of view, or has accomplished more for the unificatior of knowledge." By the term "cell-theory" is understood the teaching that all animal and plant tissues are composed of units known as "cells," which term as we shall see is inappropriate so far as the actual things designated by it are concerned. The cell-theory is a generalization which places animals and plants on a basis of similar- ity of structure. Anticipated in the Seventeenth Century: The cell doctrine was anticipated as far back as the seventeenth century, for it is to a worker of the mid-seventeenth century that we are endebted for the term "cell." Robert Hooke. an English microscopist, experimented with cork, which he declared to be made up of "little boxes or 'cells' distinguished from one another." He made thin sections by means of a pen knife and found them to be all "cellular or porous in the man- ner of a honeycomb." Malpighi and Leeuwenhoek, in the seventeenth century, made drawings which have been preserved showing the cell structure of plants; we may therefore conclude that the cell theory announced in 1838, was foreshadowed by seventeenth century work- ers. Wolff, an acute scientific observer in 1759 worked out the identity of plants and animals, as shown by their development. Hux- ley summarizes Wolff's view of the development of elementary parts as follows: "Every organ, according to him, is composed at first of a little mass of clear viscous nutritive fluid which possesses no or- ganization of any kind, but is at mo.-t compo.sed of globules. In this semi-fluid mass cavities are now developed; these if they remain round or polygonal, become the subsequent cells; if they elongate, the vessels; and the process is identically the same whether it is ex- amined in the vegetating point of a plant or the young budding organs of an animal." Bichat's Contribution: Though his connection with the cell theory is upen to question, the name of Bichat is deserving of mention in discussing it. Marie Francois Xavier Bichat. bom in France in 1771, is noted as the founder of histology. He studied in Paris under TT_ at the age of twenty-six years, a position which he held until death relieved him of his labors at the early age of thirty-one. It is related M. sr i i I, Ki I iKN. ■riii:i H II )i; S( iiwaw. '■"""""''■'■^ '" ""■ 'HIMn,,,,,,. n I.,„y |:i,,l,..y mm.I I,. M;,k..rs, I THK t'KLL TMKOIIY, 1.S38 |f that he won the attention and admiration of his chief bv making a complete extemporaneous n.port of or,e of De.saulfs ectures B ch-U dhn/st'au e"t";;ral,^ character; he ha.s been de«cr.ied as of "^'midl 8 te eve! •• nn / I '.'ifreeabie face, lijjhted by piercing and exprea- rLg> to cnvT or other^"!"/," '^'^^'^"'^ «^ '''' ^-^ -'-^le t lively in his TaLc'rswhlhu"' ^^'"""'j "''''^^'^ '" demeanour, and ?pn fh.^^ ^ ''* 01 microscopic study of the tissues. Schwann^ fn}}^7?- "^'^^ '" '>'^''^^' ^" extension of his work. B chat's cla?m him, therefore, belongs the greater honor. -<-nieiaen. and to M. Schleiden was educated for the legal profession and had enea^ed in ibe practice of law. He soon abandoned it for med cine but Xr ^"work^'^Slta'tirJLVv!'" '''''. «^ botlnr^Loc ■• 'descrfb nis work in 1«J7, stating that he arrived at a new view in reirard tn the origin of plant cells. This new view though founded upon er rsTorktSir: r' '"r'""^'^^ '''''" to%rov"okrdir"sioT tivitv q;.S ^ ^""'"^^^h ^'^ ^'■^ t«ld' '" Ijringing about new ac- ■•« '-^ J,' 5« I'ATIIl-INDKIiS OK I'llVSIOUKiY took occasion to relate to his frieiu! his observations and inferences Sdiwarm was impressed at once with the similarity to his own ob^ servations on animal tissues. They at once proceeded to Schwann's laboratory where sections of the spinal cord were examined. Schleiden recognized the nuclei as similar to those he had found in plant cells, Theodor Schwann: Schleiden and Schwann seem to have been the most diverse personalities. The former was pujrnacious and always ready to take up the jrauntlet in controversy; the latter was one of the mildest of men. We are endebted to Henle. a name familiar in micro.scopic anatomy, for what we know of tlu life ol .Schwanc This IS Menle's de.scription of him: "He was a man of .stidure beiuw the medium, with a beardless face, an almost infantile and alwavs smiling e,\pressi(.n. smooth dark brown hair, wearinjr a fur trimmed dressing gown, living in a poorly lighted room on the second floor of a restau- rant which was not even of the second class. He would pass vhole days there without going out, with a few rare books around l..,n, and numerous glass ves.sels. retorts, vials and tube.s simple . pp-ratus which he him.self made. Or 1 go in imagination to the dark and tu.sty halls of the anatomical institute where we used to work till night fall by the side of our excellent chief, Johann Muller We took our dinner in the evening, after the Kngiish fashion so tl it we mi^ht enjoy more ot the advantages of daylight." Johann Muller: The mention of Johann Muller is worth a mo- ment's digression. Muller. the son of a poor shoemaker, was born .it Coblentz in July. 1801. Perhaps it was the meagmiess of liis vorldlv passe.ssions. (or have not all the followers of Saint Crispin beei men <)1 lowly estate, that served to bring out the true metal of his charac- ■,u Surmounting the disadvantages and lack of opportunity of youth he became eventually one of the great teachers and masier minds ot (,erman science. The inspiration derived from a great teacher or personality is dinicult to comprehend much le.ss t., explain Harvey was influenced by his association with Fabricius; Bernard was similiary inspired by Magendie. The dominant physiological mind during the hr.st halt of the nineteenth century wasth.tt of Muller He was the great trainer of anatomists and physiologists. Among de.sciples during his professorship at Berlin were Virchow. the patho legist; Du Bois Reymond and Brucke, the phy.siologsits; Henle the anatomist ; Helmholtz. and Leiberkuhn. All became distinguished .scholars and professors m German universities. In glowing tribute to his master, Helmholtz said: "Wh-ever comes in contact with men ot the nrst rank has an altered scale of values in life. Such intellec- tual contact is the most interesting event that life can ofTc- " Muller's manner and gestures in the cla.ssroom re^ i ded his hearers of a Catholic priest. The way he impressed the .sl ^-ntific men of his time is best evidenced by the numerous tributes accorded his memory. Verworn .says: "He is one of tho.se monumental figures that the history of every .science brings forth but once. They change the whole aspect of the field in which they work and all later growth is influpnrpd Hv thpir Irii^-rir*-: ** A nH nf h.'.cz Tv..-.rv :-.--,-.. -.nf.~.i i....„i_ i^ Handbook of Physiology, which appeared in 1833, the same eulogist writes: "This work stands today unsurpassed in the genuinely philos- JOIIANN mli.lkh ophica] manner in wli.ch the material, .s^ oll.^n t„ vast croDortion. h. innum..rable special researches was lor the I r„n.u.d a similar serv.i for ^!:,,i!;^y ronn/'n""" ''^'""^'" " r^ 'talis!:" Attempts have been made to ac count ,n some mure or less satisfactory way for the phenome m ol litv ?h c, mT"' 'T' ""*'"*''"'' i^' 'Attention -of scientist - itm d the ch.^mico-physic or merhan-tic fheorv. Th.. maioritv f^c en t.sts of the present day maintain that hv.,.,j, organisms, > me?J machines, as opposed to the theoiv of vitalism uiiich resupj seJ^ he p.. -ence o, some "hie" principl,'. The chemico phys cist tod- y sees n thing that may not be explained by the ordinar v laws of hysics and chemistry The tendency in a.l science is to express the less^Tm pie in terms o the mon .imple. Every activitv of livinrsubstaiTe s accompanied by molecular or chemical changes in its comp. s tTon such as o.Mdation (comb.i-tion) so that chemical activity ThchTs S mUu^"V^d"?^n'l70o' f r' -'"'{-^^'t-- are phys^o-clleSc^ r.i ;^^e^vh^h':.:;s;Ss^JXt;!;;!f t^Sg^at: ^l^^'^-^^^c ^Ji^ cSnL:;;;edr ■jr.sr' ''''"' "^^^-^^^^ "^•■" ^^'^^"^^ The scientists of the period 1810 to 1850 were, for th.> most nart uui.ng ti t e also, the vitalistic theory wa.. iiat without its advo- cates who vver. armng the pupils of the great idealist plil sophe? ihe n'bn-oSst" "nT-r'^'I'il ""'f'''- '''' PhX-ologistf VonT r' int unbr\ologist. and Liebig. the chemist, were said to be lose .1 lerents to the vitalistic theory. It was not. however, unti? u'i? the date ot publication of the researches of Helmholtz on conservation of energy that vitalism received a tunning blow. Sir Mkhli Foster e.xplains fuller's vitalistic leanings by declaring that ''He was ■ vitahst only in the .sen.se that he was theoretically of'on"bnTh> even when the physico-chemical analysis of vita i phenomena had been pushed as t^ir as it could, there would still remama la?ge Sesidue t J^^TS^^^^ S S^theLniofSly^SJ^d^^eS^f^^ ^^^'^"^^'^^ ^'^ tinu;i^f;;-rti;:i?o:i^'K^rss^;;;- -^^^ -- environment just as the hvoothesi« „f .r,„.;„i„n.L'i •'.'!. '1°.".^.':'?'.°^ ^.'« woJ^ lZ\lfLZ' T^'^^'^hips of anfmal^anrpiantr^'viSS would sta> the hand of the physiologist in hi., endeavors to determine the changes which occur within the living organism." M !'.\!!!!!\!)!;!!rf or I'i I VSK !|,!)i; Y m lU'ilin, iridultrt'd Miillcr ilh'd 111 IS.")?. N'lrcliow. at his ()l)so(iuif in tile l.iilouiiijr piiiK Kvric over liis niastfr: ".My ftfl)!,. pouris havf Imth invoked U> lienor this jrrcat man. wlioni wi- all. n-piH'.sontativos of the trreat mi'dical lainily. teachers and taii^lit. practitioners and investi>j:ators. mutually lament and whose memory is still so vividly with us. Neither cares by day nor labors by ni^ht cai\ ell'ace I'rom our mind the .sorrow which we leel for his lo.s.s. ir the will m;iide them in every stajre of de velopment. It was his hand which kukU'cI my tirst step.s as a medical .student. * • ♦ ijiit i,„\^. ^,.,„ ,„„. tonjrue adeiiuately praise a man who presided over the whole domain of the science of natural life; or how can one tongue depict the master mind, wliich extended the limits of his ^reat kingdom until it became ^oo larjre for his own un divided Kovernment? * * * We have to incjuire what it was that raised .Muller to so hijrh a place in the estimation of his contempor- aries; by wliat ma^ic it was tliat envy became dumb before him, and by what mysterious means lie contrived to enchain to himself the hearts of beginners and to keep them captive through many long years? Some have said that there was .something supernatural about Muller, that his whole appearance bore the stamp of the uncommon. That this commanding influence did not whollv depend on his extra- ordinary original endownments is certain from what we know of the history of his mental greatness." Years of Di.scovery: Such was the mind from which Schwann de- rived his inspiration. The middle of the nineteenth century was the golden age— the I'ericlean age— of physiology in (Germany. To quote further Irom Schwann's biographer (Henle) : Those were great days. The microscope had been brought to such a state of perfection that it was available for accurate scientific ob.servation. The mechanics of its manufacture had besides just been simplified to such a degree that its cost was not beyond the means of the enthusiastic student even of limited means. Any day a bit of animal tissue, shaved off with a .scalpel or picked to pieces with a pair of needles might lead to im- portant ground breaking discoveries." After the publication of his work on the cell theory, Schwann wa.s appointed professor in the University of Louvain, where he re- mained nine years, after which he received a similar appointment in the University of Liege. His "Microscopical Researches into the Ac- cordance in the Structure of Plants and Animals," though of .somewhat cumbersome title, is one of the great classics of biology. He proves the identity in structure of animals and plants bv direct comparison of their elementary parts. His conclusion is that "the elementary parts of all tissues are formed of cells in an analogous, though very diversified manner, so that it may be as.serted that there is one univer- sal principle of development for the elementarv parts of organisms however, different and that this principle is the formation of cells." Virchow and "Cellular" Pathology: Anv account of the cell theory mu.st needs be incomplete with the omission of the n.ome .ind work of Kudoiph N'irchow. \'irchovv was bom in 1821 of humble parentage, his father eking out a livelihood from the combined oc- DI8C0VKUY OK I'ROTOI'LAHM n cupat ,.ns of farmer ami .small .shopkeeper. The .son who received the Rca.lenun training ol his day was of an aclive restless temiK-ran ent Virchow.s was a m.nd open to new ui..as. „f lil.eral and indeSent views on medinne, pohtics an.l religion. His open svmpathies with he leform endencus ,n IK IS wer.. such that he was oblU'd to leave Herhn t..r Uurzl.urjr, vvlure lie taught pathoio^^y and did much ori^- inal work therein He was recalled to Herlin in 1850, when he was made prof.s.M.r o! ,)atli.,lo^'y in the university. The scope of his ac- tivitu>s may be seen when it is considered that he wa.s also a member of the UeichstaK, where he became leader of the opposition andl mSterVr" h''^""'-'' of Hismark. As chairman of the finan?e n.m ?LJ fh , I 'I' •' '"■'"''"♦^ f"""^ '" ^^'- P"''^'c--^ of His city; an.i the fact that from bemg one of the most unsanitary cities Herlin h s Sea't me^nr"*; V^'" ""T' '^^'''''*^''"' '^''"'^ ^"'^ ''-" attributed p-eat measure to hi.s insistance on .sanitary reform. Virchow .stands m much the same relation to pathoio^y as Schwann to hi.stology. e 'The trn/^yr ^)l ^?'-'" "!\ '^'"'^^''■" ''"^hology." He established Ihe true and fertile doctrine that every morbid structure consists of ce iH which have been derived from preexisting celLs," or as he hm se f expre.s.sed it: "Omnis n.jlula e cellula.- Hi.s chief wo?k w^s Vjs cellular pathology published in 18.58; in it he applied the cell theory to di.seased ti.ssues. He died in 1903. nt ttii meorj The cell theory incomplete as first announced: When William Harvey published hi.s di.scover> of the circulation, .so complete was his self-appointed task that little was left for future workers The firlycogenic function of the liver is known and understood by us practically as proclaimed by Claude Bernard. The cell doctrine has a vastly different history. As announced by it's co-founders, it was lar Irom being complete. Among other inaccuracies they attached too much importance to the cell wall. The word "cell" implies a wall- ed enclosure. The cell of honeycomb or the cell of a penal institution t^o'n7h?.T^n'n.^rt"^'?^f'^ them,selves. The fundamental declara- ; rLfm ^ K ' ''^ pants and animals are built of similar units or structuies ha.s been substantiated. This is perhaps the only portion of the theory that has not been profoundly changed. fi, The discovery of Protoplasm: Perhaps of equal importance to the cell-theory was the recognition of protoplasm. Huxley called it stanci' .^hf h -^ n" ^^ ^'K -. f *^''^ ^"J^^-^'" recognized this sub- .stance, which is the basis of vital activity, in 1835. He discovered in lower animal lorms a jelly-like substance which he called "sarcode " n^l,!oi%f^''-.°^u" ^^^^^''' "^^e'y- that of watchmaker, and the TcaUon'^of hii lifl^^y '^"'""'^ ''T^. ^'"^ *" ^^"^^ «t«^d in the later vocation of his life He was an adept with the microscope and dos- sessed no .small ability as sketch artist. He showed ear?y a love for the natural sciences His contributions to science cover a rani of Sy.^&eTed^ i;1?y.'^ "-'''''' ^"^^-^*>' °^ hr^a/o^Toti life were the same thing. Max Schultze, in 1861. confirmed Cohn's «8 PATHFINDERS OF PHYSIOLOGY position and added that the cell consisted of little units of protoplasm surrounding a nucleus. The nucleus was first described by Fontana m 1871. It was regarded as a normal element of the cell by Robert Brown in 1883. It was evertually seen that many cells, especially aninml cells, are without a cell wall, h nee the conclusion that the so- called 'wall ' is not an .ssential feature of the "cell." When the cell wall is absent the protoplasm is the cell. The nucleus was found to be withm the substance of the cell and not within the cell wall. Schultze defined the cell as a globule of protoplasm surrounding a nucleus. From being regarded as an element of structure merely the cell has come to be recognized as the physiological unit within which all physiological activity *akes place. Perhaps the most authoritative as v.-ell as I'ae most recent defi- nition of protoplasm is the following significant paragraph by Star- Ung: "Tliough It may be conveaionl to havr a word suc'h as protoplasm signifying simply living material,' it is important to ri-niember tliere is no such thing as a single sul/stance— protoplasm. The reactions of every cell as well as its organiza- tion are the resultant of the molecular structure of matter of which It is built up. The gross method.s of the chemist show him that th,> composition of the proto- plasm of the muscle cell is entirely difTcrent from that of a leucocyte or white blood corpuscle. The finer methods of ■ e physiologist show him that every sort of cell in the body has its own manner of life, its own peculiarities of reaction to uniform rimngrs in its .surrijimdings. .\o individual will react in exactly the same manner as another individual even of tho same species, and the reactions of the whole organism are but the sum of the reaetions of it's constituent cells. There is not one protoplasm therefore, but an infinity of protoplasms and the use of the term can be justified only if we keep this fact in mind and use the word merely as a convenient ab'ureviation for any material endowed with life. Even in a single cell there is more than one kfna of protoplasm. In its chemical characters, in its mode of life, and in its reactions, the nucleus dilTers widely from the cytoplasm. Hoth are r .'cesspry to the life of the cell and both must be regarded according to our present ideas as 'Jiving.' In the cytoplasm itself we find structures or substances which we must regard as on their way to proto- plasm or as products of the break down of protoplasm; but in many cases It Is impossible to say whether a given material is to be regarded as lifeless or as re- active living matter, Evc.t In a single cell we may havt differentiation among its different parts, one part serving for the process of digestion while other parts are employed for purpose of locomotion. Here Hgain there must be chemical diiterences, and therefore (i.flerent protopld?m.s " A .statement of the cell theory at the present time (1913) must include fcur conceptions: (1) The cell as a rril of structure; (2) The cell as a unit of physiological activity; (Hj i ne cell as embracing all hereditary (luaiities within its substance; (4) The cell in the histori- cal development of the organism." Students of cytology have sought to find out if any uniformity of organization of protoplasm exi.sts. Accordingly we have a number of I'xplanations or theories regarding its structure. Aitmann pro- posed the granular theory. By the employment of certain hardening reagents he demonstrated dense ma.s.se.s of spherical or rod-shaped granules in all the cells of the body. In the.se he located the various vital functions, the sum total of 'A-hich constitute the life of the cell. THE NUCLEUS ^ He further maintained that these granules could come jnly by division nL^''''n'f' "^ ?,'1""''f- "^ P^''"'*''^^ VirchoWs famous phrase omms cellula e cellula mto omne granulum e granulo. The fibrillar theory presupposes net-work or clusters of fibrils knowTi as spong.o-plasm" (sponge plasm) in contra destinction to clear or structureless matter filling in the meshes of the net to which the name "hyaloplasm (glass plasm) has been given. In the Alveolar Theory of Butschli the author regards +he so- called granules as products manufactured by the hyaline protoplasm and stored up as spherul-s so that the protoplasm between the drop- lets lorm an alveolar partition— hence the name of the theory. Discussing the question as to the fluidity of protopiasm Starling regards it as 'essentially fluid in character, the form and rigidity which are acquired by most cells being due to chemical and physical difterentiation occurring in its fluids." p o' ^^ The cell consists of cytoplasm and nucleus. Cytoplasm (cell plasm) is a term lormulated by Kolliker in 1863. Though not so applied when first used, it h < come to mean the living substance of the cell body other than the nucleus. Cytoplasm contains, for the most part subs ances apparently foreign to the cell proper. In the cytoplasm 01 plant cells, for example, are stored up starches and oils. Most nerve cells contain various shaped bodies which, it is alleged repre- sent stored up energy. The passive bodies in the cytoplasm are su^ posed to represent some form of latent energy upon which the cell may draw. In the cells of any green leaf are to be found spherical masses which play a most important role in the lives of not only plants but of animals as well. By the action of the sun's rays a chemical change takes place in these bodies known to botanists as chloroplasts by which carbondioxide and water are broken down, decomposed and immediately synthetized into a difl'erent substance— carbohydrate starch, which will respond to the well known iodine test for starch' Carbohydrate IS one of the food principles. Fat.-- are also made and stored in the form of oils. In spite of the fact that the atmospheric air .surrounding the plant contain.s an abundance of free nitrogen. The plan^ cells are unable to make use of it. Nitrogen must be first combined as a nitrate, become dissolved in the soil and taken up bv the roots of the plants, or in the case of water plants, by special cells before the green matter in the leaf can be transformed into protein.' Ihe plant, therefore, has pover to make foods out of the chemical elements of air and water when these .'-ments are properly combined. This is the only source of food of both plant and animal and it is the result of cellular activity. The Nucleus: The nucleus has been recognized as a most es- sential part of the cell. It not only takes part in the complex process of cell division but dominates the rest of the cell. It is not my pur- pose to enter upon a discussion of the morphology and physiology of the animal and vegetable cell, further than it is necessary to trace the various stages of the history of its revelauon from its earliest recog- TentTeJ? I'lu'ITn'^lL I^^'^"" '^ ''''"'' '^ ^^^ — ^ --^- M PATHFINDERS OP PHYSIOLOGY ILLUSTRATIONS SHOW DIAGRARLXTICALLY THE CELL AND INDIRECT CELL DIVISION. Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 6. Fig. 6. Fig. 7. .*)„< . • "^ change in the appearance of the nucleus which indicates that a „ll l^, u "' '° '*''*^ P"""*"' consists In a rearrangement of the -, hromatin net work, Which now- ti^kcs place on the appearance of a tangled thread (Fig. 2). Ihe outwardly directed loops of this skein often correspond to the seperate por- tions into which the thread eventually breaks up. The thread gradually grows snorter and thicker, and presently becomes divided into a number of pieces kiown as chromosomes. In the chromosomes the shortening and thickening process fs continued until these bodie- arrive finally at thv form of stumpy rods each of which, often becomes bent into the form of a horse shoe. Meanwhile the nuclear membrane, breaks down, so that the hyaline sub.-'tance of tha nucleus becomes continuous with that of the coil body surrounding it, A fresh phenomenon now becomes visible. A spindle-shipod arrsnpoment makes it'.s appearance consistlrr; of a number rf minute iibrils which connect together two poirts--the poles of the spindle— .tuat-^d at opposite ends of ihe cell. The chromosomes now change their position so that they come to be in the plane of tlie equator of the spindle, and about this lire each chromosome splits longitudinally into two great por- tions (Fig. 4 and .'i). This splitting in the case of each chromosome takes place in the equatorial plane of the spindle, so that one member of each ,)dlr of daugh- ter chromosomes faces towards one |>ole of the srindle and Ihe s(.cond tow»rds the other pole. The members of each pair of daughter chromosomes nov/ b( ''in to move away from one towards the two poles of the spindle, and as they do so Ihe fir3t Indication of a dividing wall between the s<>cond new cells begins to make Its appearance in the equatorial plane. Arriving at tr° poles, the daughter chromosomes begin to elongate and to put out processes which finally meet and fuse with those of their neighbors to form the chromatin reticulum of the new nuclei. (Fig. 7.) Surrounding each new nucleus, thus developing at either pole of the now rapidly disappearing siiiiidle, a n^^w nuclear membrane mak'.s it's ap- pearance; the dividing wall in the position of the equator of the spindle develops into a complete partition in the case of plants. (The animal cell is wituout a cell wall.) The division into two new cells is thus completed. (Fig. 8.) Each new cell Is provided with a nucleus into which has entered precisely Its fair share of the chromatin which was present In the parent nucleus." — Illustration and description after Locke. TFir; CELL IN HEREDITY g,- Tho discovery of the various dyes and tissue stains afForded a wonder] ul st.mulous to the microscopic studv of tissues -is well «s to thi h-r CertSn Th T""^ I" Protopla™, which -.vill „i!"ab"S,l, „?i,i„L » .""•"" roa-sliapc >sDring IS not known. NOTi-::— It has been estimated iliat tho number of cc\k comimsitioii of rlie bod.v of an adult human being is about i five huDdr>'d tliousand millions (^tl.Vin.ooii.dnnjioO). terins into the nty-si.\ mi ;on