3o8 Fischer's Theory of Edema [Dec. 



blood, milk, and meat jnice, that hydrochloric acid Solution (0.2 

 per Cent, to 10 per cent.) may be added to the mixture in each case 

 in any /ro^or^/o^withoutinducingvisibleeffectsonthe fibrin shreds, 

 unless sufficient acid is added to provide an excess in the free 

 State. Very large quantities of acid may be added to such mix- 

 tures without inducing appreciable bloating effect.^^ If the colloids 

 in the artificial Solutions and protoplasmic liquids enumerated above 

 are combined with any proportion of the acid up to exactly their 

 maximum affinity for it (hydrochloric acid), so that the liquids 

 while strongly acid to litmus respond negatively to tests for free 

 acid, then moist fibrin shreds can remain in such fluids indefinitely 

 without swelling to any perceptible degree. Warm concentrated 

 gelatin Solutions may be put into these conditions of free and 

 combined acidity. After such Solutions have been permitted to 

 gelatinize, moist fibrin shreds which have been imbedded in the 

 resultant jellies swell perceptibly, provided the gelatinized mass 

 contains free acid, hut the shreds do not appear to absorb water 

 froni the medium if its contained acid is only in combined form. 

 It is obvious that such facts have an important bearing on any 

 theory of acid causation of edema. 



A few days ago^'* I extended these observations to enucleated 

 eyes with similar results and have conducted additional experi- 

 ments with fibrin and other colloids. After their treatment with 

 0.05 to 0.2 per cent. hydrochloric acid Solution to effect their maxi- 

 mum absorption of water, enucleated eyes and fibrin masses were 



^ Goodridge and Gies : Proceedings of the Society for Experimental Biology 

 and Medicine, 191 1, viii, p. 107. 



** " A few days " bef ore the meeting of the Biochemical Association at which 

 this subject was discussed. The results of subsequent experiments will be re- 

 ported elsewhere. 



The writer has lately commented in a very general way on some of these 

 additional results in a preliminary report in the Proceedings of the Biological 

 Section of the American Chemical Society (Biochemical Bulletin, 1911, i, p. 

 124). The foUowing remark is included in that report: "Experiments with 

 enucleated eyes (from dogs, rabbits and chickens, in Solutions of combined 

 acids) . . . failed to yield edematous results, but emphasized the need for experi- 

 ments on Solutions of biological colloids, such as serum and lymph. Fischer's 

 theory is based upon the results of experiments on solid masses in large excesses 

 of acid Solutions. He has not shown that his experimental conditions are 

 closely analogous to the natural ones in edema." 



