191 1] William J. Gies 287 



Since the formation of acid in tissues deprived of a circulation is a 

 firmly established fact — a fact which in these amputated frogs' legs 

 can be verified throiigh mere application of an indicator — we have no 

 difficulty in interpreting these experiments by saying that the ampu- 

 tated frogs' legs swell in water because the afifinity of their colloids is 

 increased through the production in them of acid. The frogs' legs 

 become edematous for the same reason that fibrin swells more in a 

 dilute acid than in pure water. If instead of being placed in distilled 

 water the amputated frogs' legs are dropped into any salt Solution, they 

 swell less than in distilled water. The higher the concentration of the 

 salt the less will the frogs' legs swell. These Statements are entirely 

 analogous to those made regarding the swelling of fibrin and gelatin 

 in dilute acid Solutions. (Page 112.) 



The anions which were found to be the most efifective in pre- 

 venting the swelling of the muscle were those of tartrate and phos- 

 phate, whereas the least effective were the bromid and chlorid 

 anions. These results, like the negative efifects of non-electrolytes, 

 were in accord with the similar data pertaining to the influence of 

 anions on the swelling of fibrin and gelatin. 



Abnormal production or accumulation of acids in the tis- 

 sues, by Chemical means, is accompanied by edema. In his dis- 

 cussion of his third thesis (pp. 121-126), Fischer gives the results 

 of several experiments intended " to prove that any condition which 

 makes for the production of acid in the tissues leads to the develop- 

 ment of an edema if a source of water is available" (p. 121). In 

 this connection he says : 



The quiekest way to put the tissues of an animal into a condition 

 that permits of the development of acids in them is to kill the animal. 

 The fact does not surprise us, therefore, that an edema develops with 

 greater ease in a dead animal than in a living one. If a living frog is 

 kept up to its neck in distilled water it suffers little Variation in weight. 

 A change in weight of 3 per cent. covers the extremes. But let the 

 frog be killed and be kept similarly covered with water and a progres- 

 sive rise in weight at once sets in. (Page 121.) 



Fischer states "that the injection of any of the poisons used 

 by Araki into the dorsal lymph sac of a frog is followed by an 

 edema. Frogs poisoned with morphin, strychnin, cocain, arsenic, 

 or uranyl nitrate all absorb amounts of water which run from 15 to 

 60 per cent. of the normal weight of the frog." (Page 123.) 



