HARVEY AND THE CIRCULATION. 237 



indeed he may have been a companion of Harvey. He 

 makes Brutus speak thus to Portia : 



" You are my true and honorable wife, 

 As dear to rne as are the ruddy drops 

 That visit rny sad heart." 



However, the great dramatist may have understood 

 the circulation in a crude sense, as even the unpro- 

 fessional of his day did. All believed the blood was 

 in motion, and that the heart had something to do 

 with the pulmonary circulation. Arabian physicians 

 phlebotomized their patients three thousand years 

 ago, and Galen knew how to raise a vein in the arm. 

 But it is not a little surprising that in using a cord to 

 make a vein full, ancient bleeders did not observe 

 that the vessel swelled below the line of contraction, and 

 not above it, as it would if the blood flowed outward 

 in the veins of the extremities, as was generally sup- 

 posed. 



As before intimated, Harvey- went to the lower 

 animals for a corroboration of his conceptions, and al- 

 ways found his labors in that field well paid. When 

 his written observations on the circulation of the frog, 

 the newt and the snake were stolen, he exhibited pro- 

 found grief. He warned his friends against relying 

 too much upon the human body for facts, as the sub- 

 ject of experiment is always dead, and the arteries 

 and one side of the heart are empty. In the lower 

 animals he could see the living heart move, and the 

 blood flow in the arteries and veins. A quotation 

 from the author will best give his manner of investi- 

 gation : 



" In the first place, when the chest of the living animal is laid 

 open, and the capsule that immediately surrounds the heart is 



