Januaey 10, 1908] 



SCIENCE 



55 



was the union between medicine and 

 chemistry effected by Paracelsus and 

 strengthened by van Helmont and Sylvius 

 in the following century, a union so inti- 

 mate that for nearly a century and a 

 quarter chemistry existed only as a part of 

 medicine until freed by Robert Boyle from 

 bonds which had become galling to both 

 partners. The story of this iatro-ehemical 

 period, as it is called, has been told by 

 Ernst von Meyer in his fascinating "His- 

 tory of Chemistry" in a way not less in- 

 teresting to the student of medicine than 

 to that of chemistry, and should be there 

 read by both. 



In reply to the question what benefit ac- 

 crued to both medicine and chemistry from 

 their mutual interaction during this period 

 von Meyer says : 



The answer is, a mutual enrichment, which did 

 almost more for chemistry than for medicine; for 

 the former was raised to a higher level through 

 being transferred from the hands of laboratory 

 workers, who were mostly uneducated, to those of 

 men belonging to a learned profession and possess- 

 ing a high degree of soientifio culture. The iatro- 

 chemical age thus formed an important period of 

 preparation for chemistry, a period during which 

 the latter so extended her province that she was 

 enabled in the middle of the seventeenth century 

 to stand forth as a young science by the side of 

 her elder sister, physics. 



Paracelsus in carrying out his program 

 that "the object of chemistry is not to 

 make gold but to prepare medicines" made 

 the pharmacist's shop a chemical labora- 

 tory and until the establishment of labora- 

 tories by Thomas Thomson and by Liebig 

 in the first quarter of the nineteenth cen- 

 tury this continued to be the only kind of 

 laboratory available for practical training 

 in chemistry. Through this portal entered 

 into the domain of chemistry Lemery, 

 Kunkel, Marggraf, Klaproth, Scheele, 

 Proust, Henry, Dumas and many others. 

 Liebig, who also began as an apothecary's 

 pupil, has graphically described these con- 

 ditions. 



That strange, iconoclastic genius, Para- 

 celsus, typifies, as no other name in science, 

 the storm and stress, the strife, the intel- 

 lectual restlessness and recklessness of the 

 sixteenth century which prepared the way 

 for the glorious light of science which 

 illuminated the following century. With 

 boundless enthusiasm minds, now fully 

 liberated from the bondage of authority, 

 entered upon new paths of philosophical 

 thought and scientific discovery and 

 achieved triumphs unequaled even in the 

 nineteenth century. The great achieve- 

 ment was the full recognition and the fruit- 

 ful application of the true method of sci- 

 ence in all its completeness. 



Although isolated and limited use had 

 been made of the method of experiment in 

 former times— I have already cited Galen 

 and I might have added physicians of the 

 Alexandrine school— the real birth of ex- 

 perimental science was toward the end of 

 the sixteenth and the beginning of the 

 seventeenth centuries. Medicine can 

 hardly be said to have presided at this 

 birth, but its influence was not absent. 

 Galileo was a student of medicine, one of 

 his teachers being the celebrated physician 

 and botanist, Cesalpinus, when in 1583 he 

 watched the great bronze lamp swinging 

 before the high altar of the Cathedral of 

 Pisa, and I question whether it would 

 have occurred to anyone without some in- 

 terest in medicine to determine the iso- 

 ehronism of the pendulum by counting the 

 beats of the pulse. It seems improbable 

 that without his medical training Galileo 

 would have made the measurement of the 

 pulse the first application of the new prin- 

 ciple and have called the instrument the 

 pulsilogon. Nevertheless we must bear in 

 mind that natural philosophers of this 

 period and throughout the seventeenth cen- 

 tury were greatly interested in anatomy 

 and physiology. Dr. Weir Mitchell in an 

 address, as charming as it is erudite, has 



