414* LIQUID PARTS OF ANIMALS. 



stance analogous to the globules of blood, though not red. The 

 uncoagulated portion coagulated by heat, and therefore contain- 

 ed albumen. 



The chyle from the sublumbar branches of the thoracic duct 

 of horses was examined likewise by Emmert and Reuss, and also 

 by Vauquelin.* It was white and opaque like milk, and con- 

 tained a white and opaque coagulum. The liquid portion was 

 coagulated by heat, by acids, and by alcohol ; and therefore con- 

 tained albumen. There was also an alkali in it, as it restored 

 the blue colour of litmus-paper reddened by an acid. Hot alco- 

 hol dissolved a fatty matter from the coagulum. The portion 

 which coagulated spontaneously contained characters analogous 

 to those tifjSMm 



Dr Marcet and Dr Prout examined, in 1815, the chyle of two 

 dogs, one of which had been fed entirely on vegetable food, the 

 other on animal food.f 



Dr Marcet described the chyle of the dog fed on vegetable 

 food in the following terms : Soon after being collected it was 

 a semitransparent, inodorous, colourless fluid, having but a very 

 slight milky hue, like whey diluted with water. Within this 

 fluid there was a coagulum or globular matter, which was also 

 transparent and nearly colourless, having the appearance and 

 consistence of albumen ovi, or of those gelatinized transparent 

 clots of albuminous matter, which are sometimes secreted by in- 

 flamed surfaces. This mass had a faint pink hue, and minute red- 

 dish filaments were observed upon its surface. It did not, as Dr 

 Prout ascertained, affect litmus or turmeric paper, nor did it 

 coagulate milk. The coagulum/ when separated from the serum, 

 parted readily with its serosity or fluid portion, and was at length 

 reduced to a very small size. The specific gravity varied from 

 1O215 to 1-022. The portion of solid matter including salts 

 varied in different specimens of chyle from 48 to 7*8 per cent. 



Both Dr Marcet and Dr Prout found the chyle of the dog 

 fed on animal food agreeing with that of the dog fed on vege- 

 table food, except that, instead of being nearly transparent and 

 colourless, it was white and opaque like cream. The coagulum 

 was also white and opaque, and had a more distinct pink hue, 

 with an appearance not unlike that of very minute blood-vessels. 

 The coagulum gradually yielded farther quantities of serous fluid, 



* Ann. de Chim. Ixxxi. 113. f Annals of Philosophy, xiii. 12. 



