FROM PARACELSUS TO HARVEY 



a martyr to science, and in whose dungeons Etienne 

 perished. 



THE COMING OF HARVEY 



The time was ripe for the culminating discovery of 

 the circulation of the blood ; but as yet no one had de- 

 termined the all-important fact that there are two 

 currents of blood in the body, one going to the heart, 

 one coming from it. The valves in the veins would 

 seem to show conclusively that the venous current did 

 not come from the heart, and surgeons must have ob- 

 served thousands of times the every -day phenomenon 

 of congested veins at the distal extremity of a limb 

 around which a ligature or constriction of any kind 

 had been placed, and the simultaneous depletion of 

 the vessels at the proximal points above the ligature. 

 But it should be remembered that inductive science 

 was in its infancy. This was the sixteenth, not the 

 nineteenth century, and few men had learned to put 

 implicit confidence in their observations and convic- 

 tions when opposed to existing doctrines. The time 

 was at hand, however, when such a man was to make 

 his appearance, and, as in the case of so many revolu- 

 tionary doctrines in science, this man was an English- 

 man. It remained for William Harvey (1578-1657) 

 to solve the great mystery which had puzzled the medi- 

 cal world since the beginning of history; not only to 

 solve it, but to prove his case so conclusively and so 

 simply that for all time his little booklet must be 

 handed down as one of the great masterpieces of lucid 

 and almost faultless demonstration. 



Harvey, the son of a prosperous Kentish yeoman, 



169 



