FROM THE SMALL INTESTINE 651 



(2) Absorption of Defibrinated Blood by the Surviving Intestine. 

 The object of these experiments is the same as the last with 

 the added possibility of eliminating imbibition. The method 

 consists in decapitating a cat, taking out a length of small 

 intestine as rapidly as possible, and filling it with a known 

 quantity of the animal's own defibrinated blood ; the gut is placed 

 in a beaker containing the same fluid through which oxygen 

 is bubbled, and the whole is placed in a thermostat kept at the 

 body temperature. Cohnheim had performed a large number of 

 similar experiments, using sometimes the same salt solution inside 

 and outside the gut, and sometimes different fluids. His results 

 showed that in an hour as much as two-thirds of the fluid in 

 the intestine might disappear. Osmosis and diffusion are excluded 

 when the same fluid is on both sides of the intestine. Filtration 

 was not excluded in many of the experiments, because in them 

 the gut showed lively peristalsis, but in other cases peristalsis 

 was absent and yet the fluid disappeared- Cohnheim was never 

 able to demonstrate directly where the fluid had disappeared to, 

 but he excluded disappearance through imbibition by weighing 

 the gut before and after the experiment, and finding that its 

 increased weight would not account for all the fluid which had 

 disappeared. He concluded, therefore, that the fluid passed 

 through the wall of the gut from the epithelium to the serous 

 surface and so into the surrounding solution ; and that this 

 transference was due to the vital activity of cells, was further 

 proved by the observation that the whole process was stopped 

 by NaF. Hamburger repeated one of Cohnheim's experiments, 

 using a "9 per cent. NaCl solution inside and defibrinated blood 

 outside the gut. He found that at the end of If hours 6*2 grm. 

 of fluid had disappeared, but he also found that the weight of 

 the gut had increased by 6*2 grm., and concluded that the fluid 

 had been absorbed by imbibition. Reid has confirmed Cohnheim's 

 observations ; he used the animal's own defibrinated blood diluted 

 with 6 per cent. NaCl solution on both sides of the intestine ; 

 but he did not weigh the gut before and after the experiments, 

 and there is therefore no certainty about the destination of the 

 absorbed fluid. On turning the gut inside out he was unable to 

 show that fluid passed now in the reverse direction. Reid, 

 however, has attempted to demonstrate by a special apparatus the 

 actual transference of fluid across surviving gut in the direction 



