20, 8 Wells, Agcaotli, and Feliciano: Philippine Rice 357 
Such observation, seemingly verified by our table, is sugges- 
tive of a method of increasing the yield; that is, it indicates 
plainly that greater returns could be obtained by simply allow- 
ing the crop a longer time in which to mature. 
Chemical analysis—The usual general methods of chemical 
analysis were followed in this work. All analyses were per- 
formed in duplicate to check results; those that did not agree 
within permissible errors were repeated. 
Sampling.—Representative samples were taken from different 
parts and levels of a 1-kilogram sack of rice, from which the 
hulls were removed by grinding the kernels in a mortar, utmost 
care being taken that no polishing was done to the rice grains. 
Then 100 unbroken kernels were sorted out at random and 
weighed, the weight representing the weight of 100 kernels of a 
variety. 
METHODS OF ANALYSIS 
Moisture——Moisture was determined by drying a known 
weight of a sample (2 to 5 grams) in an electric oven at 100° C. 
until a constant weight was obtained. The loss in weight rep- 
resents the moisture present. 
Ether extract.—Fats were determined by extracting a weighed 
sample with ether in a Soxhlet apparatus for forty-eight hours; 
the ether extract was then freed from ether and moisture, and 
weighed. This result was checked by drying the ether residue 
and finding the loss in weight. 
Protein.—The indirect. method of obtaining protein was used. 
Nitrogen was first determined by Gunning’s modification of 
Kjeldahl’s nitrogen determination and then this value was con- 
verted by a factor (6.25) into protein. 
Crude fiber.—Crude fiber was determined by boiling the res- 
idue from the ether extract with 1.25 per cent sulphuric acid 
for a half hour, then washing it free from acid; the product 
was again boiled with 1.25 per cent sodium hydroxide for an- 
other half hour. The undissolved residue was washed free from 
alkali, filtered, dried, and weighed. This weight minus the 
weight of the ash represents the crude fiber. 
Ash.—The ash was determined by incinerating carefully the 
dried sample from the moisture determination. The weight of 
the whitish or grayish residue, free from carbon, left after care- 
ful incineration represents the ash content. 
Carbohydrates—Carbohydrates, starch, etc., other than crude 
fiber, were obtained by difference. 
