191 1] William J. Gies 307 



and salins reduces the hydrophilic tendency of the colloids in the 

 presence of acid, but he does not discuss this Observation in its rela- 

 tion to similar conditions in cells and tissues. 



The diffusion tendencies and effects in edematous tissues are 

 ignored. Does lactic acid accumulate in an edematous tissue as 

 lactic acid or in the form of lactates, or does it pass out of the 

 tissue as acid or as lactates? What is the minimal concentration 

 of lactic acid which is able, in Solutions containing the physiological 

 salins in their ordinary proportions, to bring about swelling of any 

 of the colloids or colloidal masses which Fischer used in his experi- 

 ments? Does this proportion of lactic acid ever occur in edema- 

 tous tissue? Do acid salts favor or retard the tendency of lactic 

 acid to increase the affinity of colloids for water? 



Fischer did not consider the probable or possible bearing of 

 definite chemical relationships between the colloids and the acid in 

 the case. Are definite unions or relationships between tissue col- 

 loids and lactic acid essential to the edematous manifestation of col- 

 loidal hydrophilia? If so, do the tissue colloids and lactic acid 

 form a hydrophilic partnership in the presence of such substances 

 as di-sodium hydrogen phosphate and sodium bicarbonate? 



Fischer refers to CO2 as one of the factors in the production 

 of edema but does not show why the large quantities of CO2 which 

 are normally produced in tissues fail to induce water accumulation 

 in them. Does the intracellular CO2 have any effect directly or 

 indirectly on the power of lactic acid to cause edema? 



The experimental procedure in Fischer's work is not always the 

 best that might have been adopted. Fischer's experiments were 

 performed with dry masses, and with solid parts of organisms. 

 How his theory could be experimentally verified with blood serum 

 or tissue juice (dissolved colloids) in the absence of "membranes" 

 or " partitions " is not suggested. How do dissolved colloids, as 

 compared with solid colloids, behave in the presence of lactic acid, 

 and phosphates, and bicarbonates ? Do the interstitial dissolved 

 colloids have any influence in restraining the development of edema 

 at any stage of the process? 



Goodridge and I find, when moist shreds of fibrin are severally 

 suspended in gelatin Solution, peptone Solution, fresh egg white, 



