182 
Philippine Journal of Science 
1920 
for definite knowledge of the nature of the proteins in feeds been 
felt. Ten or fifteen years ago chemists were satisfied if they 
knew their crude-protein content, and they did not consider it 
important or necessary to get a more definite knowledge of its 
nature. The present work was intended as a preliminary study 
of this great problem and it was decided, first, to apply the Van 
Slyke method to the protein of copra meal taken as a whole and, 
second, to determine the proteins soluble in different solvents, 
both qualitatively and quantitatively. 
Analyses of other feeding stuffs have been made by Grindley, 
Joseph and Slater(7) and by Grindley and Slater. (8)* Gort- 
ner,(4) who is emphatically against the idea of making a direct 
comparison between the analysis of protein unseparated from 
the feeding stuff and that of a pure protein, nevertheless admits 
that much comparative data can be obtained from the work of 
these authors. At present, the department of agricultural chem- 
istry of the Philippine College of Agriculture is perfecting a 
plan for conducting a series of nutrition experiments with copra 
meal ; and, because a more intimate knowledge of the protein of 
copra meal is necessary for this work, the carrying on of the 
experiments reported in this paper is believed to be justified. 
Individual proteins will be isolated and studied later. 
DETERMINATION OF NITROGEN DISTRIBUTION IN COPRA MEAL 
The copra meal, which was kindly furnished by Chesley, Conde 
and Company through Dr. Baldomero L. Roxas, of Manila, was 
ground fine, and on analysis showed the following composition : 
Table 1. — Composition of copra meal. 
Moisture 
Per cent. 
11.3 
Oil 
12.2 
Crude protein 
20.1 
Ash 
5.5 
Crude fiber 
13.2 
Carbohydrates 
37.0 
The ground meal was then dried under vacuum by Browne’s 
method (3) and extracted with ether for eight hours. Two-gram 
samples were treated with hot water (at about 90° C.) for one 
^ Since the manuscript for this paper was prepared, H. C. Eckstein, 
and H. S. Grindley, Journ. Biol. Chem. 37 (1919) 373, have published 
a decidedly improved method “to determine directly the combined amino- 
acids of feedingstuffs by the application of the Van Slyke Method for the 
determination of the characteristic groups of amino-acids of proteins.” 
