ON ABSORPTION FROM THE PERITONEAL 

 CAVITY.* 



BY LAFAYETTE B. MENDEL. 



THERE is abundant experimental evidence to indicate that 

 when an intravascular fluid is separated from an extra vascular 

 one of different composition, an interchange of substances will 

 take place between them. Given a separating membrane, e. g., 

 a capillary wall, sufficiently permeable to the substances in 

 solution, the two fluids will manifest a tendency to become 

 equalized in composition. Thus substances originally dissolved 

 in the extravascular fluid only may pass into the intravascular 

 solution according to the established principles of osmosis.f 

 That substances foreign to the blood can in this way be 

 absorbed into the circulation directly through the blood-vessels 

 has long been known.J In investigating the absorption of 

 dissolved substances with reference to the channels by which 

 they enter the circulation from the connective tissue spaces, it 

 has been a customary procedure to introduce readily detectable 

 compounds into these spaces, and to watch for their appearance 

 in the blood or lymph stream under various conditions. The 

 outcome of these researches has been to attribute to the blood- 

 vessels an important r6le in absorption from connective tissue 

 spaces, quite in accord with the requirements of physical 

 diffusion ; although it has by no means been denied that the 

 lymphatics also may be engaged in the transfer from the 

 tissue cavities to the blood. 



The problem of absorption from the pleura! and peritoneal 



* Reprinted from the Amer. Jour, of Physiol., vol. ii. 

 t Cf. Roth, Archiv fur Physiologie,1898, p. 642. 



t Cf. Schaefer's Text-book of Physiology, 1898, i, p. 303; Munk, I., Archir 

 fur Physiologic, 1895, p. 387. 



