Heart and Blood 93 



period when all the parts, like the heart itself in the 

 beginning, are still white, and save in the veins there 

 is no appearance of redness, you shall see nothing in 

 the seat of the liver but a shapeless collection, as it 

 were, of extravasated blood, which you might take for 

 the effects of a contusion or ruptured vein. 



But in the incubated egg there are, as it were, two 

 umbilical vessels, one from the albumen passing entire 

 through the liver, and going straight to the heart ; 

 another from the yelk, ending in the vena portae ; for 

 it appears that the chick, in the first instance, is entirely 

 formed and nourished by the white ; but by the yelk 

 after it has come to perfection and is excluded from 

 the shell ; for this part may still be found in the 

 abdomen of the chick many days after its exclusion, 

 and is a substitute for the milk to other animals. 



But these matters will be better spoken of in my 

 observations on the formation of the foetus, where 

 many propositions, the following among the number, 

 will be discussed : Wherefore is this part formed or 

 perfected first, that last ? and of the several members : 

 what part is the cause of another ? And many points 

 having special reference to the heart, such as : Where- 

 fore does it first acquire consistency, and appear to 

 possess life, motion, sense, before any other part of the 

 body is perfected, as Aristotle says in his third book, 

 De partibus Animalium ? And so also of the blood : 

 Wherefore does it precede all the rest ? And in what 

 way does it possess the vital and animal principle ? 

 And show a tendency to motion, and to be impelled 

 hither and thither, the end for which the heart appears 

 to be made ? In the same way, in considering the 

 pulse : Wherefore one kind of pulse should indicate 

 death, another recovery ? And so of all the other 

 kinds of pulse, what may be the cause and indication 

 of each. So also in the consideration of crises and 

 natural critical discharges ; of nutrition, and especially 

 the distribution of the nutriment ; and of defluxions of 



