HEART AND BLOOD. 33 



else to it, heat, spirit, perfection, must be inquired into by 

 and by, and decided upon other grounds. So much may suf- 

 fice at this time, when it is shown that by the action of the 

 heart the blood is transfused through the ventricles from the 

 veins to the arteries, and distributed by them to all parts of 

 the body. 



So much, indeed, is admitted by all [physiologists], both 

 from the structure of the heart and the arrangement and action 

 of its valves. But still they are like persons purblind or groping 

 about in the dark ; and then they give utterance to diverse, con- 

 tradictory, and incoherent sentiments, delivering many things 

 upon conjecture, as we have already had occasion to remark. . 



The grand cause of hesitation and error in this subject ap- 

 pears to me to have been the intimate connexion between the 

 heart and the lungs. When men saw both the vena arteriosa [or 

 pulmonary artery] and the arterise venosse [or pulmonary veins] 

 losing themselves in the lungs, of course it became a puzzle to 

 them to know how or by what means the right ventricle should 

 distribute the blood to the body, or the left draw it from the 

 venae cavse. This fact is borne witness to by Galen, whose 

 words, when writing against Erasistratus in regard to the origin 

 and use of the veins and the coction of the blood, are the fol- 

 lowing : l " You will reply," he says, "that the effect is so; that 

 the blood is prepared in the liver, and is thence transferred to 

 the heart to receive its proper form and last perfection; a state- 

 ment which does not appear devoid of reason ; for no great and 

 perfect work is ever accomplished at a single effort, or receives 

 its final polish from one instrument. But if this be actually 

 so, then show us another vessel which draws the absolutely 

 perfect blood from the heart, and distributes it as the arteries 

 do the spirits over the whole body." Here then is a reason- 

 able opinion not allowed, because, forsooth, besides not seeing 

 the true means of transit, he could not discover the vessel which 

 should transmit the blood from the heart to the body at large ! 

 But had any one been there in behalf of Erasistratus, and of 

 that opinion which we now espouse, and which Galen himself 

 acknowledges in other respects consonant with reason, to have 

 pointed to the aorta as the vessel which distributes the blood from 



1 De Placitis Hippocratis et Platonis, vi. 



