466 ABSORPTION. 



absorption of this poison simply by its effects npon the sys- 

 tem, it must be assumed that, during digestion, it cannot be 

 absorbed by the mucous membrane of the stomach and small 

 intestine, notwithstanding that it is exceedingly soluble. 



It has also been shown by Segalas, that liquids which 

 immediately disorganize the tissues, such as concentrated 

 nitric or sulphuric acid, cannot be absorbed. 1 Another 

 important peculiarity in absorption has been demonstrated 

 by Mialhe, who has shown that solutions which readily co- 

 agulate the albumen of the circulating fluids are absorbed 

 very slowly. 2 This is explained on supposition that there is 

 a coagulation of the albuminous fluids with which the ab- 

 sorbing membrane is permeated, which interferes with the 

 passage of liquids. These substances are nevertheless taken 

 up by the blood-vessels, though rather slowly. 



The modifications which are due simply to the physical 

 conditions of liquids to be absorbed are chiefly manifested 

 out of the body, and will be considered in connection with 

 the subject of endosmosis. 



Influence of the Condition of the Blood and the Vessels on 

 Absorption. After loss of blood or deterioration of the nutri- 

 tive fluid from prolonged abstinence, absorption generally 

 takes place with great activity. This is well known, both as 

 regards the entrance of water and alimentary substances and 

 the absorption of medicines. It was at one time quite a com- 

 mon practice to bleed before administering certain remedies, 

 in order to produce their more speedy action upon the sys- 

 tem. The increase in the activity of the absorption of poi- 

 sons by bleeding was strikingly illustrated by Magendie in 

 some of his earliest experiments. He found that when an 

 animal had been bled copiously, the effects of poisons, which 

 were ordinarily manifested after two minutes, appeared with- 



1 SEGALAS, Note sur quclques Points de Physiologic. Journal de Physiologie^ 

 Paris, 1857, tomeiv., p. 287. 



2 MIALHE, Chimie appliquee d la Physiologic, Paris, 1856, p. 200. 



