378 ON GENERATION. 



reason wherefore, when parts are first produced, and before 

 they have taken upon them the performance of their respective 

 duties, they all look bloodless and pale, in consequence of which 

 they were formerly regarded as spermatic by physicians and 

 anatomists, and in generation it was usual to say that several 

 days were passed in the milk. The liver, lungs, and substance 

 of the heart itself, when they first appear, are extremely white ; 

 and, indeed, the cone of the heart and the walls of the ven- 

 tricles are still seen to be white, when the auricles, replete with 

 crimson blood, are red, and the coronary vein is purple with 

 its stream. In like manner, the parenchyma of the liver is 

 white, when its veins and their branches are red with blood ; 

 nor does it perform any duty until it is penetrated with blood. 



The blood, in a word, so flows around and penetrates the 

 whole body, and imparts heat and life conjoined to all its parts, 

 that the vital principle, having its first and chief seat there, may 

 truly be held as resident in the blood ; in this way, in common 

 parlance, it conies to be all in all, and all in each particular part. 



But so little is it true, as Aristotle and the medical writers 

 assert, that the liver and the heart are the authors and com- 

 pounders of the blood, that the contrary even appears most 

 obviously from the formation of the chick in ovo, viz. : that the 

 blood is much rather the fashioner of the heart and liver ; a 

 fact, which physicians themselves appear unintentionally to 

 confirm, when they speak of the parenchyma of the liver as a 

 kind of effusion of blood, as if it were nothing more than so 

 much blood coagulated there. But the blood must exist before 

 it can either be shed or coagulated; and experience palpably 

 demonstrates that the thing is so, seeing that the blood is al- 

 ready present before there is a vestige either of the body or of 

 any viscus; and that in circumstances where none of the 

 mother's blood can by possibility reach the embryo, an event 

 which is vulgarly held to occur among viviparous animals. 



The liver of fishes is always perceived of a white colour, 

 though their veins are of a deep purple or black ; and our 

 fowls, the fatter they become, the smaller and paler grows the 

 liver. Cachectic maidens, and those who labour under chlo- 

 rosis, are not only pale and blanched in their bodies generally, 

 but in their livers as well, a manifest indication of a want of 

 blood in their system. The liver, therefore, receives both its 



