198 OF ABSORPTION AND SANGUIFICATION. 



duced into the stomach have undergone the modification into peptones, they 

 have acquired the power of traversing animal membranes with comparative 

 facility. As the conditions for the absorption of these substances are alike 

 present in the stomach and intestines, it is probable that this process takes 

 place through the whole length of the alimentary tube, though chiefly in 

 the intestine, as the presence of acids is unfavorable to its active perform- 

 ance; a view which receives support from the experiments of Busch 1 upon 

 the woman with a duodenal fistula, in whom it was fouud that a consider- 

 able portion of the saccharine, and about one-third of the albuminous com- 

 pounds taken as food, were absorbed before reaching the intestines. Fuuke' 2 

 observed, also, that when solutions of peptone were introduced and secured 

 by ligature in determinate lengths of the intestines of living rabbits, and 

 permitted to remain for two, four, and six hours, the more concentrated the 

 solution, the greater was the activity with which the absorption was accom- 

 plished in a given time; but that a remarkable difference occurred from 

 what might have been anticipated, where a definite quantity of the solution 

 of peptone was presented to double the extent of surface, very little more 

 being then absorbed, or at least nothing like double the amount in the same 

 time. He further found that the amount absorbed in the living animal by 

 no means stands in direct relation to the duration of the experiment, the 

 process taking place with far more energy during the first hour than subse- 

 quently; and the same facts were also observed in experiments upon the ab- 

 sorption of sugar made by Becker. 3 



[In absorption by the bloodvessels, change of place or motion on the part 

 of at least one of the fluids separated by the animal membrane is of pri- 

 mary importance. Were this not the case an equilibrium would soon be 

 obtained and the current be discontinued; but the rapidity of the circula- 

 tion in the capillaries carries away the materials or fluids which have been 

 absorbed, and leaves room for the absorption of more; as demonstrated in 

 the experiment of Dr. Robinson, Fig. 82. 



On the same principle, fulness of the capillaries retards osmosis ; whence 

 an important practical deduction follows with regard to the treatment of 

 poisoned wounds. If by any means at our disposal we can bring about a 

 congestion of the bloodvessels surrounding the wound, the tendency to the 

 absorption of the poison will be greatly diminished. And this is the prin- 

 ciple upon which the application of a cupping-glass to the wound, as revived 

 by Sir D. Barry, or a ligature placed between the wound and the central 

 organ of the circulation, or even suction applied to the wound itself, will 

 sometimes prevent the action of the poison. 



The experiments of Christison and Magendie are illustrations of these 

 facts. 



The former, after tying a ligature about the limb of a dog, introduced 

 some poisonous material into the connective tissue beyond the ligature. So 

 long as the ligature was allowed to remain, very little absorption took place ; 

 but immediately on the removal of the ligature and the renewal of the cir- 

 culation, the animal succumbed. (Christison on Poisons, p. 39.) Magendie 

 injected a colored liquid into the cavity of the peritoneum of an animal, 

 having first also produced a plethoric condition of the bloodvessels by in- 

 jecting them with water. So long as the plethoric condition remained, the 

 colored fluid was not absorbed from the peritoneal cavity; but immediately 

 on opening a bloodvessel, the colored fluid disappeared rapidly by absorp- 

 tion. 



1 Arcliiv f. I'ath. A nut. uml Physiologie, 1858, B'l.'xiv, p. 140 



l'liysiologi<>, 4th edit., ISC,:;, p. :;. r )7. 



f. \viss. Znologie, 1854, t. v, p. 137 ct scq. 



