CHARACTERS OF THE CHYLE. 293 



of the blood ; as might be expected, from the fact, that the fluid portion 

 of the lymph must have its origin in that which has transuded through 

 the blood-vessels : the absolute quantity, however, is rather less. A 

 similar analysis of the Chyle of a cat by Nasse, has given results very 

 closely correspondent with that of Dr. Rees : for the proportion of 

 water was 90-5 per cent. ; and of the 9-5 parts of solid matter, the 

 albumen, fibrine, and extractive amounted to more than 5, and the fat 

 to more than 3 parts. Dr. Rees has also analyzed the fluid of the 

 Thoracic duct of Man, which consists of chyle with an admixture of 

 lymph ; and he found this to contain about 90-5 per cent, of water, 7 

 parts of albumen and fibrine, 1 part of aqueous alcoholic extractive, and 

 not quite one part of fatty matter, with about J per cent, of salines. 

 The composition of this fluid more resembles that of the lymph than that 

 of the chyle; the proportion of the fatty to the albuminous matter 

 being small. This was probably due to the circumstance, that the sub- 

 ject from which it was obtained (an executed criminal) had eaten but 

 little for some hours before his death. 



516. The characters of the Chyle are not the same in every part of 

 the Lacteal system ; for the fluid undergoes a very important series of 

 changes in its characters, in its transit from the walls of the intestines 

 to the receptaculum chyli. The fluid drawn from the lacteals that tra- 

 verse the intestinal walls, has no power of spontaneous coagulation; 

 whence we may infer that it contains little or no Fibrine. It contains 

 Albumen in a state of complete solution, as we may ascertain by the 

 influence of heat or acid in producing coagulation. And it includes a 

 quantity of fatty matter, which is not dissolved, but suspended in the 

 form of globules of variable size. The quantity of this evidently varies 

 with the character of the food ; it is more abundant, for instance, in the 

 chyle of Man arid the Carnivora, than in that of the Herbivora. It is 

 generally supposed that the milky colour of the chyle is owing to the 

 oil-globules ; but Mr. Gulliver has pointed out that it is really due to 

 an immense multitude of far more minute particles, which he has 

 described under the name of the molecular base of the chyle. These 

 molecules are most abundant in rich, milky, opaque chyle ; whilst in 

 poorer chyle, which is semi-transparent, the particles float separately, 

 and often exhibit the vivid motions common to the most minute mole- 

 cules of various substances. Such is their minuteness, that, even with 

 the best instruments, it is impossible to determine/ either their form or 

 their dimensions with exactness ; they seem, however, to be generally 

 spherical ; and their diameter may be estimated at between l-36,000th 

 and l-24,000th of an inch. Their chemical nature is as yet uncertain ; 

 they are remarkable for their unchangeableness, when submitted to the 

 action of numerous reagents, which quickly aflect the proper Chyle- 

 corpuscles ; whilst their ready solubility in Ether would seem to indi- 

 cate that they are of an oily or fatty nature. 



517. The milky aspect which the serum of blood sometimes exhibits, 

 is due to an admixture of this molecular base. It may be particularly 

 noticed, when blood is drawn a few hours after a full meal, that has been 

 preceded by a long fast. By recent experiments it has been found, that 

 the serum begins to show this turbidity about half an hour after t 



