HARVEY 



7 



II. — Harvey (i 578-1657). 



The De Motu Cordis et Sanguinis in Animalibus 

 was published at Frankfurt in 1628. And it begins 

 with these words : Cum multis vivorum dissectioni- 

 dus, uti ad manum dabantur : — 



" When by many dissections of living animals, 

 as they came to hand, I first gave myself to observ- 

 ing how I might discover with my own eyes, and 

 not from books and the writings of other men, the 

 use and purpose of the movement of the heart in 

 animals, forthwith I found the matter hard indeed, 

 and full of difficulty : so that I began to think, with 

 Frascatorius, that the movement of the heart was 

 known to God alone. For I could not distinguish 

 aright either the nature of its systole and diastole, 

 or when or where dilatation and contraction took 

 place ; and this because of the swiftness of the 

 movement, which in many animals in the twinkling 

 of an eye, like a flash of lightning, revealed itself 

 to sight and then was gone ; so that I came to 

 believe that I saw systole and diastole now this 

 way now the other, and movements now apart and 

 now together. Wherefore my mind wavered ; I had 

 nothing assured to me, whether decided by me or 

 taken from other men : and I did not wonder that 

 Andreas Laurentius had written that the movement 

 of the heart was what the ebb and flow of the 

 Euripus had been to Aristotle. 



"At last, having daily used greater disquisition 

 and diligence, by frequent examination of many and 

 various living animals — multa frequenter et varia 

 animalia viva introspiciendo — and many observa- 

 tions put together, I came to believe that I had 



