312 Fischer' s Theory of Edema [Dec. 



in this connection what we find in print. Fischer's readiness in dis- 

 cussion, and his overflowing fullness of the subject, have evidently 

 betrayed him into such errors of presentation. 



These criticisms, offered as they are in the interest of further 

 practical development of our knowledge of the subject, happen to 

 be in general harmony with some of Fischer's remarks on his theory 

 that are practically ignored by him after their casual presentation 

 in a few words but which I believe are of more importance than 

 that commonly ascribed to rhetorical ahernatives. Let me restate 

 Fischer's most general formulation of his theory: 



A State of edema is induced whenever, in the presence of an ade- 

 quate supply of water, the afünity of the colloids of the tissues for 

 water is increased above that which we are pleased to call normal. The 

 accumulation of acids within the tissues brought about either through 

 their abnormal production, or through the inadequate removal of such as 

 some consider normally produced in the tissues, is chiefly responsible for 

 this increase in the affinity of the colloids for water, though the possi- 

 hility of explaining at least some of the increased affinity for water 

 through the production or accumulation of suhstances which affect the 

 colloids in a way similar to acids or through the conversion of colloids 

 having but Utile affinity for water into such as have a greater affinity 

 must also he hörne in mind. (Page 99.) 



I am convinced that great possibilities of usefulness lie buried 

 in the italicized part of the foregoing quotation. I believe this 

 despite the fact that Fischer practically discards this significant 

 alternative in behalf of his theory of direct acid causation of edema. 

 The following quotations from Fischer's book are far more 

 important, it seems to me, than his "passing" references would 

 indicate : 



Under the influence of proteolytic ferments ordinary gelatin can be 

 converted into Beta-gelatin. As already pointed out, Wolfgang Ost- 

 wald's studies show this to be capable of greater swelling than the 

 unchanged gelatin. It is therefore conceivable that in inflammation 

 (whether in the eye or elsewhere) an increased affinity of the tissue 

 colloids for water and a consequent edema may result merely in con- 

 sequence of the "autolytic" Changes that occur in the injured tissues, 

 even when no abnormal storage or production of acids in the part 

 occurs. (Footnote, page 129.) 



