514 The Philippine Journal of Science 1922 
probably dissolve a small quantity of those substances, and the 
alcohols which no doubt dissolve a considerable quantity. 
With the exception of carbon tetrachloride, the figures show- 
ing the percentage extraction with the various solvents increase 
gradually with the time interval. With ether the increase is 
very gradual. Benzene, petroleum ether, and chloroform show 
a slightly greater increase, while acetone and the alcohols show 
a rather large increase. Absolute alcohol shows the greatest 
increase. Methyl alcohol gives a greater percentage extraction 
than any of the other solvents. 
As carbon tetrachloride and benzene give about the same 
results as ether, our experiments would seem to indicate that 
either of these solvents could ordinarily be used in place of 
ether; and, if desired, the results could be calculated to the 
ether standard. These solvents are more easily handled in a 
tropical climate than ether, since they boil at a much higher 
temperature, and carbon tetrachloride also has the advantage 
that it is not inflammable. 
Shrader * gives figures showing the speed of evaporation of 
various solvents. The data were obtained by allowing 5 cubic 
centimeters of various solvents to evaporate from an alberene 
dish under similar conditions. The results showed that ether 
evaporates in 2 minutes, carbon tetrachloride in 11.5 minutes, 
and benzene in 12.5 minutes. In so far as evaporation is con- 
cerned, carbon tetrachloride and benzene would evidently be 
very desirable solvents for routine work in the’Tropics. 
The figures (Table 3) showing the percentage extraction with 
carbon tetrachloride increase up to a period of six hours, after 
which there appears to be no further extraction. These results 
indicate that carbon tetrachloride probably dissolves less of the 
nonfatty substances in the copra cake than any of the other 
solvents and since carbon tetrachloride requires less time for 
extraction it would appear to be a very suitable solvent. 
HYDRAULIC CAKE 
In addition to our work on expeller cake we also carried out 
a few experiments on the extraction of hydraulic cake (Soxhlet 
method) with different solvents for a six-hour period only. 
The results are recorded in Table 4, which gives also, for 
purposes of comparison, the figures previously given in Table 3, 
showing the extraction of expeller cake for a six-hour period. 
*Shrader, J. H., Chem. Met. Eng. 25 (1921) 99. 
