58 



SCIENCE 



[N. S. Vol. XXVII. No. 



portant results. The beginnings of our 

 knowledge of digestion and of secretion 

 and even of the chemistry of the blood and 

 other fluids are to be traced in the main to 

 the iatro-chemieal school, and the study of 

 fermentation, although this was not con- 

 ceived in the same sense as to-day, of gases, 

 salts, acids and alkalis was of importance 

 to medicine as well as to chemistry. 



There never has been a period in medical 

 history, not even in recent years, when so 

 determined an effort was made to convert 

 medicine into applied physics and chem- 

 istry as that in the seventeenth century. 

 Descartes 's dualistic philosophy, which left 

 no more room for the intervention of other 

 than mechanical forces in the organized 

 world than in the inorganic, had great in- 

 fluence upon the minds of physicians as 

 well as of physicists. Galileo had founded, 

 and a line of great experimental phi- 

 losophers from him to Newton had vastly 

 extended, the science of dynamics, which 

 then seemed to many, as in potentiality it 

 may be, as applicable to all the activities 

 of living beings as to the inanimate uni- 

 verse. There came in the first quarter of 

 the century the greatest physical discovery 

 in the history of physiology, that of the 

 circulation of the blood, which opened the 

 large biological tract of hasmodynamics to 

 rewarding study by the new physical 

 methods. The balance, the pendulum- 

 chronometer, the thermometer and other 

 newly invented instruments of precision 

 wereturned to good account in anatomical, 

 physiological and pathological investiga- 

 tions, and physicians began to count, to 

 weigh, to measure, to calculate and to dis- 

 cover a world of form and structure hidden 

 from their unaided vision. Such chem- 

 istry as existed was pursued almost ex- 

 clusively by physicians and primarily in 

 the interest of medicine. 



What wonder, then, that physicians who 

 came under the influences of this great 



awakening in physical science and took no 

 small part in its advent and promotion, 

 should have entertained hopes, soon 

 doomed to disappointment, of the benefits 

 to medicine from application of the new 

 knowledge and have promulgated hypoth- 

 eses and systems of doctrine which seem 

 to us so false and extravagant! Great as 

 was the advance in physical knowledge, it 

 was utterlj^ inadequate for many of the pur- 

 poses to which the iatro-physicists and 

 iatro-chemists applied it, and to this day 

 many of their problems remain unsolved. 



Grateful we should be for valuable dis- 

 coveries and new points of view which 

 medicine owes to these men, often so un- 

 justly criticized, but the time had come for 

 men of our profession to resume the Hip- 

 pocratic method of collecting facts of ob- 

 servation within their own clinical field, 

 and Sydenham, of all the physicians of his 

 century the name, next to Harvey's, most 

 honored by medical posterity, in calling 

 out, " back to Hippocrates! " turned the 

 face of medicine again toward nature. 



There are interesting points of compari- 

 son between Sydenham's position in the 

 history of medicine, and that of his fellow- 

 countryman and contemporary, John Ray, 

 in natural history. I am sorry that my 

 profession, which has fostered so many 

 ardent students of nature, including Lin- 

 njeus and Agassiz, the respective bi-cen- 

 tenary and centenary anniversaries of 

 whose birth have been celebrated with such 

 enthusiasm in the year now closing, can 

 not claim this greatest naturalist of his 

 century. Both Sydenham and Ray stood 

 apart from the gi-eat scientific movement 

 of their day; both, little influenced by 

 theory or tradition, concentrated their 

 efforts strictly within their respective fields 

 of observation, and both introduced new 

 methods of studying their subjects. As 

 Ray, the plants and animals, so Sydenham 

 described diseases as objects of nature, his 



