502 STUDIES IN GENERAL PHYSIOLOGY 
a larger number of organic acids, especially of the fatty series, 
which I wish to report here. It is clear that these apparent 
exceptions to the theory of electrolytic dissociation in the 
case of the organic acids must yield material for understand- 
ing the chemical changes which go on in living matter. 
The experiments were made as the previous ones. Five 
or 10 c.c. of a one-tenth normal solution of the acids were 
added to 100c.c. of a NaCl solution. The gastrocnemius of 
a frog was introduced into such a solution and its increase 
in weight determined at certain intervals. 
The solutions which contained 10 c.c. of a one-tenth nor- 
mal acid in 100 c.c. of a 0.7 per cent. NaCl solution—in 
which therefore the concentration V equaled 110—-gave more 
constant results than those solutions in which V equaled 210. 
The following table gives the results of several series of 
experiments with a series of acids when V equaled 110. The 
Arabic figures give the increase in weight which each muscle 
showed, expressed in per cent. of its original weight after 
remaining for one hour in the solution. 
(V=110) 
I m | Wr] wv | v_ | vr | Avge 
Formic acid............ 5.6% | 4.6% | 5.6% | 5.0% | 4.2% | 5.0% | 5.02 
Acetic acid............. 4.7 |3.4 (3.3 | 4.7 sas ax | 3.9 
Trichloracetic acid..... 7.3 | 6.8 eve oes sus itis 7.1 
Lactic acid............. 6.7 |6.8 |8.0 |8.0 |6.9 | 7.1 | 7.2 
Valerianic acid......... 4.4 |5.7 ;4.9 |... cae ws | 5.0 
Mandelic acid.......... 6.5 | 7.5 | 7.8 ace 7.2 
1g Oxalic acid.......... 6.4 |6.3 | 6.0 | 8.8 6.9 
14g Succinic acid........ 6.1 | 4.7 |6.0 |... 5.6 
44 Malic acid........... 4.0 |4.4 |5.4 16.8 |]... 5.1 
14 Dextro-tartaric acid .| 5.8 | 6.4 |6.6 | 7.1 | 5.9 6.3 
44 Racemic acid........ 6.3 |5.4 |6.8 |... tase 6.2 
We will now compare with this series the degree of dis- 
sociation of these acids when V=110.' 
1Caleulated according to OSTWALD, ‘‘ Ueber die Affinitatsgrdéssen organischer 
Sauren,” Abhandlungen der Sdchsischen Gesellschaft der Wissenschaften, Vol. XV, 
p. 89. 
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