128 
current of hot air, driven by a fan, is passed. In Trinidad,'® British 
West Indies, there is now in operation a rotary hot-air drier which, it 
is stated, is better than any other apparatus now in use. 
For the purpose of testing the efficiency of the stationary form of hot-air drier, 
a double-walled, rectangular galvanized-iron box, having an internal capacity of 
about 0.2 cubic meter, was constructed. Three galvanized-iron trays, perforated 
at one end, were set in this box in such a manner that the stream of hot air 
entering through a 20-centimeter pipe at the bottom was compelled to pass over 
each in turn before escaping at the top of the apparatus. A constant current of 
air was obtained by means of a small electric fan which was connected with a 
section of 15-centimeter pipe, so arranged that it could be heated by a small 
kerosene stove to any desired temperature. The apparatus had a maximum 
capacity of 24 nuts split in halves or 12 nuts when shredded. 
Haperiment I.—Four nuts were split in halves and placed on the 
bottom tray. 
Temperature of entering air, 56° C. 
Temperature of escaping air, 51° C. 
Time of drying, 20 hours. 
‘The copra dried at this comparatively low temperature was very white 
and of the best quality. A sample of oil expressed from it contained 
0.08 per cent free acid. 
Kxperiment I1.—The meat from twelve nuts was shredded by hand and 
treated for one day in the same manner as in the preceding experiment ; 
it was then allowed to stand at room temperature over night and com- 
pletely dried on the following day. The substance in the bottom tray 
naturally desiccated much more rapidly than in the other two, therefore 
as soon as one tray was completely dry it was removed and replaced by the 
one just above it. 
Temperature of entering air, 56° C. 
Temperature of escaping air, 50° C. 
Actual time of drying: 
Top, 143 hours. 
Middle, 124 hours. 
Bottom, 93 hours. 
‘The less completely dried copra in the two upper trays became slightly 
“soured” while standing over night. This caused a slight increase in 
free acid as follows: 
| Per cent 
Tray. | free fatty 
| acid. 
| i ae 
| LOD nnbAdmateeeiubesnegncccpuasecs— = 0, 32 
OR acta ocacoescndaned 0.16 
| Metwote. i235... tt ee | 0.13 
° Journal @Agriculture Tropicale (1904), 103. 
