NEw YoRK AGRICULTURAL EXPERIMENT STATION. ~ 63 
plished. The bran was allowed to soak over night in warm water, 
a slight acid fermentation being induced. When the water showed 
a slight acidity to litmus, the bran was placed in sacks and thor- 
oughly leached with more water. After being air-dried it was ready 
for use. 
The high phosphorus ration was made up from oat straw, hominy, 
whole wheat bran and wheat gluten. Through the use of the wheat 
giuten which contained from 70 to 75 per cent. of protein, it was 
easy to regulate the protein supply so as to make it fairly uniform 
in the two rations. 
METHOD OF SAMPLING AND ANALYSIS. 
The rations were weighed out at several different times during 
the course of the experiment and each time this was done sam- 
ples were taken of the various feeds. The similarity in composi- 
tion of these several portions indicates that the mixing and sam- 
pling were thoroughly accomplished. The milk, urine and feces 
were taken directly to the laboratory and immediately weighed and 
sampled, excepting that the noon and night’s milk was kept in an 
icebox until morning when the product for an entire day was 
thoroughly mixed together and sampled. Reserve samples of milk 
and urine were always kept, fermentative changes in these being 
prevented by the use of formaldehyde and toluol. The feces were 
thoroughly mixed by prolonged stirring and five pound samples 
of the fresh material were taken for drying and for nitrogen de- 
terminations. These samples were dried over steam coils at a 
temperature not exceeding 60° C. 
In general the analytical methods of the A. O. A. C. were fol- 
lowed. During some of the time the fat in the milk was estimated 
both by the Babcock and ether extraction methods. Neumann’s 
method was used in all the total phosphorus determinations. For 
the separation of inorganic from organic phosphorus the method 
described in Bulletin No. 238 of this Station was employed. This 
method also gave an opportunity to estimate what we have called 
“fixed” phosphorus and which probably quite closely represents 
the phosphorus of the true nucleo-proteids and nucleins. In the 
urine only total phosphorus was determined, as attempts to separ- 
ate inorganic from organic forms, even if the latter existed in appre- 
ciable quantities, were futile. | 
