THE UTILIZATION OF CHERRY BY-PRODUCTS. 7 
Soxhlet extractor. Extraction was made with ether and continued 
until the material was completely exhausted. By this process a yield 
of 8.3 per cent of a pale-brown fixed oil was obtained. By the same 
process the pits from the imported cherries yielded 4.5 per cent of a 
deep-brown, rancid-smelling oil. 
The crude oil thus obtained was not only deeply colored but pos- 
sessed a characteristic odor of rancidity, due to the presence of free 
volatile fatty acids. In order to free the oil of the objectionable 
color and odor it was subjected to the following refining process: 
The oil was introduced into a flask and live steam was conducted 
through the mass until the distillate which contained the free vola- 
tile acids possessed no appreciable odor and was no longer acid to 
litmus. While hot, the oil was separated from the water in the flask 
by means of a separatory funnel, treated with kaolin (fuller's earth), 
and the mass filtered through filter paper in a hot filtration funnel. 
The filtered oil was pale golden yellow in color, with a distinctly 
nutlike taste and with no suggestion of rancidity. 
EXTRACTION OF OIL FROM THE KERNELS BY PRESSURE. 
Hydraulic pressure was not found applicable to the pits, because of 
the low yield of oil. It was necessary, therefore, to crack the pits 
and remove the kernels. This was accomplished by slowly feeding 
the pits into a mill having vertical grinding plates set to grind very 
coarsely, so that a mere cracking of the shells resulted without crush- 
ing the kernels. The cracked pits were first put through a round- 
hole sieve with openings sixteen sixty-fourths of an inch in diameter 
and then through another sieve with openings of thirteen sixty- 
fourths of an inch. This removed the coarser parts of the shells. 
A final separation was made by passing the material through a " wild- 
oat " sieve with oblong meshes measuring seven sixty-fourths by one- 
half of an inch. The last screening effected a reasonably complete 
separation of the kernels from the shells. 
It is very important that the mill be fed with a slow, continuous 
stream of pits, and care must be exercised in order not to crush the 
kernels, otherwise they are apt to separate into halves and the halves 
pass through the final sieve. By this process 28 per cent of the pits 
was found to consist of kernels. 
The laboratory press available for the extraction of the oil from the 
kernels was not entirely adequate for obtaining the best results. A 
pressure of 2,750 pounds to the square inch was applied to the finely 
ground kernels, the expression being conducted in the cold. A yield 
of 21 per cent of a pale golden yellow oil, with a pleasant nutlike 
odor and taste, was thus obtained. With a commercial hydraulic 
press of the latest type, equipped for hot expression, a much higher 
yield would undoubtedly result. Working on a commercial scale 
