14 BULLETIN 350, U. S. DEPARTMENT OF AGRICULTURE. 
per cent, and the kernel oil 82.8 per cent. From the physical proper- 
ties it is very probable that the bulk of the liquid acids consists of oleic 
acid. The specific gravity of pure oleic acid is reported as 0.895 at 
25° C. and the index of refraction at the same temperature as 1.4603. 
These figures agree very closely with those recorded in Table V. The 
descriptions of the acids obtained are also very similar to the 'descrip- 
tion of official oleic acid, which is described as yellowish or brownish 
yellow in color, with a peculiar lardlike odor and taste. 
That the bulk of the liquid acids consists of oleic acid is further 
substantiated by the close agreement of the iodin value of these acids 
as found in the cherry oils and the iodin value of commercial oleic 
acid. Although the iodin value of the pure acid is 90, some oleic acids 
of commerce have values as high as 100 to 110. 
The somewhat low neutralization values found in the cherry oils 
are probably due to slight changes in the fatty acids, as it is well 
known that these are apt to decompose. 
In approximating the composition of cherry oil, only the kernel oil 
was considered. It was found that this oil consisted of 8.96 per cent 
of solid acids, which were composed of stearic acid with a possible 
trace of palmitic acid. Since the glycerid stearin contains 95.73 per 
cent of stearic acid, it was found by calculation that the oil contained 
9.36 per cent of stearin. The original oil consisted of 82.8 per cent of 
liquid acids, which, calculated as oleic acid and reduced to terms of 
olein (olein contains 95.7 per cent oleic acid), corresponds to 86.5 per 
cent of the glycerid olein. 
A brief summar}' of the results obtained by the chemical examina- 
tion indicates, therefore, the following approximate composition of 
cherry kernel oil: Olein, 86.5 per cent; stearin, including a possible 
trace of palmitin, 9.36 per cent ; the remaining portion of the oil con- 
sists of smaller amounts of free acids, A'olatile acids, and unsaponifi- 
able matter. 
REACTION OF THE OIL TOWARD REAGENTS. 
Color reactions are frequently applied to fixed oils, although per- 
haps more for the purpose of detecting adulterations than for deter- 
mining the quality. Certain reagents produce characteristic color 
reactions; therefore, Avhen it is desired to compare related oils it is 
often expedient to ascertain the behavior of the oils toward reagents. 
Since this investigation deals with an oil which is closely related to 
several well-known commercial oils, a number of color reactions were 
therefore determined and comparison was made with the color reac- 
tions obtained from the affiliated oils extracted by means of ether in 
this laboratory. The results are presented in Table VI. 
