XXII 



THE PHYSIOLOGICAL EFFECTS OF IONS. II 1 

 THE experiments described in this paper are a continua- 

 tion of the experiments in my first paper on this subject in 

 three directions. 2 It will be shown by a longer series of 

 experiments that the organic acids behave differently from 

 the inorganic. While the physiological effects of the latter 

 are determined by the concentration of hydrogen ions, this is 

 apparently not the case with the fatty acids, inasmuch as the 

 degree of dissociation and the physiological effects of the 

 fatty acids do not run parallel. We shall not attempt to 

 explain this apparent exception until we have further experi- 

 mental data at our disposal. We may, however, think of 

 the possibility that the fatty acids undergo a partial oxidation 

 in the muscle. 



1 have shown in my first paper that a muscle does not 

 change much in weight in a 0.7 per cent. NaCl solution 

 during the first hour, but that it increases greatly in weight 

 when only a trace of an acid is added. This increase in 

 weight can be explained by assuming that the hydrogen ions 

 of the acid act in the muscle hydrolytically like enzymes and 

 in this way increase the osmotic pressure in the muscle. 

 While the effect of inorganic acids in sufficiently dilute solu- 

 tions was quantitatively exactly a function of the number of 

 hydrogen ions contained in the unit of volume of the solu- 

 tion, no such relation seemed to exist for the organic acids. 

 I pointed out that this exceptional behavior from the theory 

 of dissociation could be explained through secondary chem- 

 ical processes. I have since made a series of experiments with 



iPfliigers Archiv, Vol. LXXI (1898), p. 457. 



2 " On the Physiological Effects of Ions, I," Part II, p. 450. 



501 



