34 MOTION OF THE 



the heart to the rest of the body, I wonder what would have been 

 the answer of that most ingenious and learned man ? Had he 

 said that the artery transmits spirits and not blood, he would 

 indeed sufficiently have answered Erasistratus, who imagined 

 that the arteries contained nothing but spirits ; but then he 

 would have contradicted himself, and given a foul denial to that 

 for which he had keenly contended in his writings against this 

 very Erasistratus, to wit, that blood in substance is contained in 

 the arteries, and not spirits ; a fact which he demonstrated not 

 only by many powerful arguments, but by experiments. 



But if the divine Galen will here allow, as in other places he 

 does, " that all the arteries of the body arise from the great ar- 

 tery, and that this takes its origin from the heart ; that all these 

 vessels naturally contain and carry blood j that the three semi- 

 lunar valves situated at the orifice of the aorta prevent the return 

 of the blood into the heart, and that nature never connected them 

 with this, the most noble viscus of the body, unless for some most 

 important end " if, I say, this father of physic admits all these 

 things, and I quote his own words, I do not see how he 

 can deny that the great artery is the very vessel to carry the 

 blood, when it has attained its highest term of perfection, from 

 the heart for distribution to all parts of the body. Or would he 

 perchance still hesitate, like all who have come after him, even 

 to the present hour, because he did not perceive the route by 

 which the blood was transferred from the veins to the arteries, 

 in consequence, as I have already said, of the intimate con- ' 

 nexion between the heart and the lungs ? And that this dif- 

 ficulty puzzled anatomists not a little, when in their dissections 

 they found the pulmonary artery and left ventricle full of thick, 

 black, and clotted blood, plainly appears, when they felt them- 

 selves compelled to affirm that the blood made its way from the 

 right to the left ventricle by sweating through the septum of 

 the heart. But this fancy I have already refuted. A new 

 pathway for the blood must therefore be prepared and thrown 

 open, and being once exposed, no further difficulty will, I believe, 

 be experienced by any one in admitting what I have already 

 proposed in regard to the pulse of the heart and arteries, viz. 

 the passage of the blood from the veins to the arteries, and its 

 distribution to the whole of the body by means of these vessels. 



