n] Circulation of the Blood. 53 



that the blood which was carried to a part along the arteries 

 came back away from the part along the veins, the same blood, 

 altered it might be in the transit but still the same blood, 

 such attempts became at once possible. The spirits became at 

 once mere qualities of the blood, their names might be retained, 

 but the virtue had gone out of the names ; the names were no 

 longer a hindrance to exact inquiry as to what took place in an 

 organ when it entered into a phase of activity and how that 

 activity was influenced by or influenced the blood. 



In the second place Harvey's work was a shining example 

 for all future inquirers. The patient examination of anatomical 

 features, if possible a comparison of those features in the same 

 organ or part in more animals than one, the laying hold of some 

 explanation of the purpose of those features suggested by the 

 features themselves, and the devising of experiments, by vivi- 

 section or otherwise, which should test the validity of that 

 explanation, that was Harvey's threefold method. It had it is 

 true been followed before, by Vesalius and succeeding anatomists, 

 and indeed in a measure by Galen himself; but these had for 

 the most part been content with the explanation suggested by 

 structure, and had rarely used the test of experiment, though 

 as we have seen Vesalius at least saw its value. It was 

 Harvey's great merit to have boldly used the experimental 

 method, to have set a lesson, to the zealous following of which 

 the progress of physiology after him has been largely due. 



All great men have their detractors ; and Harvey has been 

 no exception. Many writers have attempted to claim for others 

 than him the credit of his great work. To Servetus, Realdus 

 Columbus and Caesalpinus and to others has been attributed in 

 turn the merit of the discovery of circulation. I trust I have 

 been able to put in a clear light what were the several con- 

 tributions to the progress of knowledge of the above three men, 

 and how wholly they fell short of Harvey. I need not tarry to 

 speak of Carlo Ruini of Bologna, who, though no professor, 

 wrote in 1598 a very admirable book on the Anatomy of the 

 Horse, in which he shewed that he had grasped, in a striking 

 manner, the actions of the valves of the heart. One name 

 however needs to be dealt with, that of Petrus Paulus Sarpi, 



