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found that by careful manipulation the grated meat from four nuts 
could be dried in about two hours so as not to contain more than 6 per 
cent of moisture. The only objection to this method consists in the 
difficulty of regulating the speed with which the ground meat passes 
from one end of the apparatus to the other. This is dependent on four 
factors: (1) The number of revolutions per minute, (2) the angle of 
inclination, (3) the specific gravity of the coconut meat, and (4) the 
speed of the entering current of hot air. In the machine used here an 
unfortunate tendency toward a separation of the moist from the dry 
copra appeared; the dry particles, being lighter, were held back by the 
current of air or even blown out through the upper end of the tube, 
whereas the moist and consequently heavier pieces passed through too 
quickly. When these mechanical difficulties are solved this should prove 
the ideal method for drying coconut meat for oil-making purposes. 
Vacuum drying.—The apparatus used was a small, barrel-shaped iron 
chamber, about 34 centimeters in diameter and in length, insulated with 
asbestos and heated by three hollow steam plates upon which the substance 
to be dried was placed. The pump connected with this drier gave a 
vacuum of about 660 millimeters (absolute pressure of 100 millimeters). 
Experiment 1.—Four coconuts (the maximum capacity of the ap- 
paratus) were split in halves, after removing the outer husk, and kept 
in the drier for three hours. The meat had then contracted sufficiently 
to allow of its being removed from the shell. During this time the tem- 
perature had gradually risen from 30° to 80°. The meat was then 
subjected to a further drying during four hours, at the end of which time, 
though not perfectly anhydrous, it was fully as dry as the ordinary 
commercial article. 
Actual time of drying, 7 hours. . 
Maximum temperature, 80° C. 
Vacuum, 635 millimeters. 
Steam pressure, about 0.7 kilo per square centimeter (10 pounds). 
Kexperiment I1.—The preceding experiment was repeated under prac- 
tically the same conditions, except that the nuts were allowed to dry 
completely without removing the shell. 
Time of actual drying, 8 hours. 
Maximum temperature, 80° C. 
Vacuum, 648 millimeters. 
Steam pressure, about 0.7 kilo per square centimeter (10 pounds). 
Kxperiment I1T.—An attempt was made to shorten the time of drying 
by increasing the steam pressure and having the machine hot before 
putting in the nuts, the initial temperature being 75°. 
Actual time of drying, 5} hours. 
Maximum temperature, 85° C. 
Vacuum, 640 millimeters. 
Steam pressure, about 4.2 kilos per square centimeter (60 pounds). 
