226 



Chapter IX. 



LACTEAL ABSORPTION, 



The Chyle, of which we have now traced the 

 formation, is a fluid of uniform consistence, 

 perfectly bland and unirritating in its properties ; 

 and the elements of which have been brought 

 into that precise state of chemical composition, 

 which renders them fit to be distributed to 

 every part of the system for the purposes of nou- 

 rishment. In all the lower orders of animals 

 it is transparent; but the chyle of Mammalia 

 often contains a multitude of globules, which 

 give it a white colour, like milk. Its chemical 

 composition appears to be very analogous to 

 that of the blood into which it is afterwards con- 

 verted. From some experiments made by my 

 late much valued friend Dr. Marcet, it appears 

 that the chyle of dogs, fed on animal food alone, 

 is always milky, whereas in the same animals, 

 when they are limited to a vegetable diet, it is 

 nearly transparent and colourless.* 



The chyle is absorbed from the inner surface 

 of the intestines by the Lac teals, which commence 



* Medico- Chirurgical Transactions ; vi. 630. 



