6o Stiles and J 0rgensen— Studies in Permeability . IV. 
strength of the alcohol does result in increased exosmosis. In a concentra- 
tion of 2 m. methyl alcohol the permeability increases at a considerably 
more rapid rate than in the case of a solution of m. concentration, though the 
difference is only noticeable after three or four hours’ immersion in the 
solutions. A solution of 3 m. methyl alcohol produces more marked 
exosmosis from the first, but after three hours the rate of exosmosis gradually 
increases for some hours until this rate is reduced owing to reduction in the 
concentration of electrolytes inside the cell, the maximum exosmosis not 
being reached till about 16 to 20 hours. 
With 4 m. methyl alcohol the same state of affairs is observable, the 
permeability increasing more than in the case of 3 m. from the beginning. 
The marked increase in the rate of exosmosis begins sooner, after about an 
hour and an half, and the total exosmosis approximates to the maximum 
Fig. 6. Exosmosis of electrolytes from potato in solutions ot ethyl alcohol of various concentrations. 
after 9 or 10 hours’ immersion. Higher strengths of alcohol show an 
increased rate of exosmosis during the early stages, the preliminary period 
during which the permeability increases comparatively slowly being reduced 
in duration with increasing concentration of alcohol. In 10 m. methyl 
alcohol, as the accompanying curves show, the preliminary stage must 
occupy considerably less time than 20 minutes. 
The most numerous series of concentrations was used in the case of 
ethyl alcohol. The following were the solutions employed : o-o, 075 m., 
i°om., i*5 m., 2 m., 4m., 6 m., 8 m. The results are shown in Fig. 6. 
They are exactly similar to those obtained with methyl alcohol, except that 
a smaller molecular concentration is required to produce the same effect on 
the permeability of the cell. Thus a 1-5 m. solution of ethyl alcohol 
produces changes in permeability of the cell similar to those produced by 
