AI.COHOI.S AND FATIGUE PROCESSES 
167 
tal muscles has been the only available criterion on this point. 
From comparative uniformity of the resulting curves obtained on 
repeated trials it would seem that this criterion could be relied 
upon within the limits of experimental procedure. 
The alcohols used throughout the experiments were obtained 
from different sources; the methyl, ethyl and n-butyl were re- 
distilled in the organic laboratory here at the college ; the n-propyl 
was obtained from Merck; n-amyl, nonyl, decyl were obtained 
from the Eastman Kodak Laboratories. The last two named are 
put on the market as 'TechnicaF’ and were not used in this 
series of experiments. The secondary octyl was purified by the 
Eastman Kodak Company while its isomer e capryl was ''practical’' 
and was redistilled here in the organic laboratory. Eastman’s 
"technical” heptyl alcohol was used but for the most part records 
with this alcohol were unsatisfactory, probably because of its 
oily nature. 
EXPERIMENTATION 
Ranges in suitable concentrations of the 'alcohols vary widely 
according to the specifically desired physiological result. For 
example, Overton in his study of narcosis of tadpoles found the 
range to lie between 0.57 mols per L. for methyl to .0004 mols 
per L. for octyl. Contrasted to these concentrations are obser- 
vations by Fuhner and Neubauer in producing Haemolysis where 
the range varied from 7.34 mols per L. for methyl, to .004 for 
octyl, and Vernon’s range in the destruction of indophenol oxidase 
was even higher in the first four members of the series that he 
tried, being 10.5 to 14 mols per L. for methyl to .032 to 0.9 mols 
for butyl. These last figures correspond very closely to those 
found to apply to isocapillary solutions, e. g., from 14.0 mols 
per L. for methyl to 0.14 mols for amyl. On this basis it was 
necessary to compute ranges of- concentrations over rather wide 
limits, and to select therefrom those concentrations that promised 
to produce the desired physiological effects, i. e., bearing in mind 
that solutions of strengths above the optimum concentration would 
likely be too toxic and would result in depression or inhibition 
(Anaesthesia) of the muscular response, and on the other hand 
those below would probably have a stimulating (sensitization) 
eflfect. 
After making a number of preliminary observations the concen- 
trations of the alcohols, volumes per cent, were selected as 
given in the following table: 
