ITS QUANTITY. 291 



gradually diminished during the passage of the chyle to the blood, 

 and this may be owing to its participation in the formation of cells, 

 that is to say, of chyle-corpuscles, which are very rich in fat, and 

 partly to its transition into a state of saponification, as we may 

 judge from the quantity of the alkaline salts of the fatty acids 

 present in the chyle of the thoracic duct. 



No direct observations have as yet been made concerning the 

 pathological relations of the chyle. 



We cannot regard the question of the quantity of chyle which 

 enters the blood in a given time, as satisfactorily settled. 

 Cruikshank* assumes the quantity of chyle which is hourly mixed 

 with the blood to be 4 pounds. His calculation rests upon an ob- 

 servation of the rapidity of the motion of the chyle in the mesentery 

 of a dog, which he found to be four inches in a second, and hence 

 he assumed a similar rate of velocity in the thoracic duct. But 

 independently of the untenability of the latter position, the rapidity 

 of the motion of the chyle in the lymphatics of the mesentery 

 depends upon many different relations, which, from their variable 

 character, can scarcely be adequately appreciated in observations 

 made during vivisection. Magendie, who endeavoured to deter- 

 mine the quantity of the chyle by opening the cervical portion of 

 the thoracic duct of well-fed dogs, and observing the quantity which 

 flowed in a given time, found that half an ounce escaped in five 

 minutes, which was at the rate of six ounces in the hour. Bidder, 

 who has made similar experiments on dogs that had been previously 

 strangled, arrived at nearly similar results ; but unfortunately, as this 

 observer remarks, such experiments scarcely warrant us in drawing 

 any definite conclusion. If, for instance, as Vierordtf observes, 

 the ascent of the chyle be arrested by cutting the thoracic duct, 

 which is one of the most efficient causes of its motion, it must not 

 be forgotten, that this operation may be followed by too abundant 

 a discharge ; for here, as in the analogous but more strongly 

 marked case of the blood, there will necessarily be an afflux of 

 juices from all sides, which must increase in an extraordinary 



* [Lehmann refers in a foot-note to p. 78 of Ludwig's translation of Cruik- 

 shank's "Anatomy of the Absorbing Vessels" as bis authority for this assertion. 

 All .that Cruikshank says is : " The chyle in the lacteals of the mesentery of 

 dogs, in some of my experiments, evidently run through a space of four inches in 

 a second, which is twenty feet in a minute." 1st Ed. Lond., 1780, p. 29. In 

 neither his first nor his second edition (published in 1790) does he attempt to 

 determine the quantity of the chyle. G. E. D.] 



t Arch. f. phys. Heilk. Bd. 7, S. 281285. 



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