LETTERS. 609 



from the yelk always so terminate. In the selfsame way, 

 therefore, as the chick is nourished from a nutriment, (viz. 

 the albumen and vitellus,) previously prepared, even so does 

 it continue to be nourished through the whole course of 

 its independent existence. And the same thing, as I have 

 elsewhere shown, is common to all embryos whatsoever : the 

 nourishment mingled with the blood, is transmitted through 

 their veins to the heart, whence moving on by the arteries, it 

 is carried to every part of the body. The foetus when born, 

 when thrown upon its own resources, and no longer imme- 

 diately nourished by the mother, makes use of its stomach 

 and intestines just as the chick makes use of the contents of 

 the egg, and vegetables make use of the ground whence they 

 derive concocted nutriment. For even as the chick at the 

 commencement obtained its nourishment from the egg, by 

 means of the umbilical vessels (arteries and veins) and the 

 circulation of the blood, so does it subsequently, and when it 

 has escaped from the shell, receive nourishment by the mesen- 

 teric veins ; so that in either way the chyle passes through the 

 same channels, and takes its route by the same path through 

 the liver. Nor do I see any reason why the route by which 

 the chyle is carried in one animal should not be that by which 

 it is carried in all animals whatsoever; nor indeed, if a cir- 

 culation of the blood be necessary in this matter, as it really 

 is, that there is any need for inventing another way. 



I must say that I greatly prize the industry of the learned 

 Pecquet, and make much of the receptacle which he has dis- 

 covered ; still it does not present itself to me as of such im- 

 portance as to force me from the opinion I have already given ; 

 for I have myself found several receptacles of milk in young 

 animals ; and in the human embryo I have found the thymus 

 so distended with milk, that suspicions of an imposthume 

 were at first sight excited, and I was disposed to believe that 

 the lungs were in a state of suppuration, for the mass of 

 the thymus looked actually larger than the lungs themselves. 

 Frequently, too, I have found a quantity of milk in the nipples 

 of new-born infants, as also in the breasts of young men 

 who were very lusty. I have also met with a receptacle full 

 of milk in the body of a fat and large deer, in the situation 



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