466 
Philippine Journal of Science 
1919 
Each of the six classes of oil A was divided into four parts, 
of about 30 grams each, and stored March 24, 1917, under the 
conditions given in Table II. 
Table II . — Conditions during storage. 
Designation. 
Conditions. 
Rancidity fac- 
tors. 
Sd 
Light. 
Air. 
Air and light. 
SI 
Od 
01 
The sealed tubes contained practically no air space (about 
0.5 cubic centimeter). The open samples were in 100 cubic 
centimeter bottles closed only with a cotton plug; in these the 
oil formed a layer 2 centimeters deep. The temperature during 
storage was about 30° C. 
Another sample of oil, B, was prepared in the same manner 
as oil A, but was found to have only 0.1 per cent acidity. This 
was divided into six parts as described in Table I. These were 
stored on April 19, 1917, exposed to air and light, under the 
same conditions as series 01 of oil A and will, therefore, be 
designated as series OIB. 
On April 11, 1919, the thirty samples were transferred to 
glass-stoppered bottles and their examination for rancidity was 
begun. During the time required for the various determina- 
tions, which were made in duplicate, the samples were kept 
as much as possible in a refrigerator to prevent further change. 
The results of the examination are given in Table III, in which 
the first twenty-four samples are from oil A, and the remaining 
six from oil B. 
EXPLANATION OF TABLE III 
Rancidity factors . — The abbreviations a, 1, s, i, m, n, are 
used to designate air, light, fat-soluble enzymes, fat-insoluble 
enzymes (together with possible microorganisms), moisture, 
and nonfatty material, respectively. 
Acidity . — The first column gives the determinations made 
by Parker before storing the oil. Evidently sterilization caused 
a rise from 0.37 to 0.52 in the case of oil A. 
Iodine number . — The Hanus method was used. Duplicates 
differed by about 0.04. No data on the original iodine numbers 
were available, but they may be taken as being close to those 
of the sealed samples, since the latter had no opportunity of 
