292 CHYLE. 



degree the vis a tergo, however small it may he, hy which the 

 chyle is propelled. The lymph will at all events flow more 

 abundantly, rendering the result of the enquiry so uncertain as to 

 prevent any proper solution of the physiological question con- 

 cerning the quantity of the newly-formed and elaborated nutrient 

 matter which passes through the chyle-vessels. 



Vierordt proposes the following method for computing the 

 quantity of the chyle which passes into the blood of an adult in 

 24 hours : As 100 grammes of dry nitrogenous matters are daily 

 consumed by an adult man, and as the chyle contains about 4 of 

 such matters, the quantity of chyle daily formed will amount to 

 2J kilogrammes, or about 5 pounds.* Vierordt himself observes that 

 this calculation does not admit of a comparison with those of the 

 earlier inquirers, because the lymph mixed with the chyle and 

 flowing from the lymphatics, is not included in the computation, 

 and because the quantity cannot be even approximately com- 

 puted, owing to our uncertainty regarding the quantity of the lymph. 

 The quantity of albumen which the chyle receives in the mesen- 

 teric glands, is excluded by Vierordt in his calculation, because he 

 regards it as too small to require notice. To those who believe 

 with Vierordt, that nitrogenous nutrient matters can only reach 

 the blood through the lacteals, his mode of calculation may serve 

 as an index of the quantity of the chyle ; but all who concur with 

 Frerichs and other observers, in assuming that the peptones are 

 resorbed by the stomach and intestinal canal through the veins 

 an opinion which appears to be borne out by many circumstances 

 will necessarily attach more weight to the direct observations of 

 Magendie and Bidder, than to Vierordt's calculation. 



On the other hand, Vierordt would have approximated more 

 nearly to the truth, if, instead of selecting the nitrogenous con- 

 stituents, he had based his calculation on the quantity of fat in the 

 chyle and the amount of fat which was daily resorbed in the intes- 

 tinal canal. We know from Boussingault'sf admirable experiments 

 on ducks, that these animals are not able to take up more than 

 19-2 grammes in 24 hours, however rich in fat their food may be. 

 We are, therefore, led to presume that there may be a similar limit 

 to the resorption of fat in other animals. From numerous experi- 

 ments on cats Schmidt, Bidder, and LenzJ have indeed convinced 



* [The kilogramme = 2.2 pounds avoirdupois ; hence 2f kilogrammes = 5J 

 pounds. G. E. D.] 



t Ann. de Chim. et de Phys. 3 Ser. T. 19, p. 117125. 



t De adipis concoctione et absorptione. Dorp. Liv. i860, p. 6279. 



