PHYSIOLOGICAL EFFICIENCY OF ACIDS 139 
In this case then the paradoxical result is obtained that 
one-thousandth normal butyric acid is more effective in causing 
membrane formation than one-twelfth normal hydrochloric 
acid! A blind opponent of the dissociation theory could wish 
for no more striking material than that here adduced. Yet 
it would be a serious mistake to make use of these results 
against the theory of electrolytic dissociation. 
TABLE XXIV 
Length of Exposure) 15/500 N HC1 | 40/500 N HCl 
2minutesi. . 2... 
0 20% 
3iminutes.. ..... 4% 20 
4 minutes....... it 20 
5 minutes....... 5 4 
Giminutes....... 30 
The disagreement of the facts here mentioned with the dis- 
sociation theory is only an apparent one and finds its solution 
in the consideration of the following two facts. In the first 
place, with regard to the causing of membrane formation, only 
the mass of acid that has actually entered the egg comes into 
consideration; and secondly, the velocity with which the different 
acids enter the egg is a function of their chemical constitution. 
If this is true, we should find indications that the connections 
mentioned above between the constitution and physiological 
effect of acids in reality show relations between constitution 
and the rapidity of absorption of the acids by the egg. We 
will produce two proofs of this, one indirect and the other direct. 
The indirect evidence consists in the fact that the effects of the 
homologous alcohols in the experiments of Overton, Fihner 
and Neubauer are analogous to the effects of the fatty acids 
in ours. Now Hans Meyer as well as Overton has pointed out 
that the activity of the alcohols runs parallel to their coefficient 
of partition between lipoid and water. The relative physio- 
logical activity of the alcohols must therefore be determined 
