514: ABSORPTION. 



after a few hours' exposure, the clot contracted to about half 

 its original size, precisely like coagulated blood, and the se- 

 rum became perfectly separated. In one instance, in the dog, 

 the volume of serum, after twenty-four hours of repose, was 

 about twice that of the contracted clot. 1 Milne-Edwards, quo- 

 ting from an unpublished memoir presented by Colin to the 

 Academy of Sciences, in 1858, states that the lymph does not 

 coagulate in the vessels, even when the circulation is inter- 

 rupted. 2 This may be the case under ordinary conditions, 

 when the vessels are simply tied ; but it was found by Flan- ( 

 drin, 3 that coagulation obstructed the tubes which he intro- 

 duced into the thoracic duct so completely that he was able 

 to obtain but a small quantity of fluid ; a difficulty which is 

 also mentioned by Colin, who states that " the clearing of 

 the tube rarely suffices to reestablish the flow, for the coag- 

 ulum formed in the tube is prolonged for a greater or less 

 distance into the interior of the thoracic duct." 4 Coagula- 

 tion of lymph in the vessels during life, if it occur at all, 

 must be exceedingly infrequent, notwithstanding that the 

 flow of lymph and chyle is very slow . and irregular, com- 

 pared with the circulation of the blood, and is subject, prob- 

 ably, to frequent interruptions. 



Although numerous analyses have been made of lymph 

 from the human subject, the conditions under which the fluid 

 has been obtained render it probable that in the majority of 

 instances it was not entirely normal. It will be necessary, 

 therefore, to compare these analyses with observations made 

 upon the lymph of the inferior animals ; as in the latter, this 

 fluid has been collected under conditions which leave no 

 doubt as to its normal character. In the experiments of 



1 D ALTON, Lectures on the Physiology of the Circulation. The American 

 Medical Monthly and New York Review, December, 1860, p. 411. 



8 MILNE-EDWARDS, Leconssur la Physiologic, Paris, 1859, toine iv., p. 556, note, 



3 Loc. cit. 



4 COLIN, op. cit., tome ii., page 111. 



