252 
Journal of Agricultural Research voi xxvn, no. 5 
EXPERIMENTAL 
As already stated, the method of hydrolysis employed for the treatment 
of grain hulls in this investigation was that of Beckmann. The apparatus 
consisted of a tank constructed of 2-inch spruce planking, coated on the 
inside with asphalt, and provided with a strainer and outlet tap at the 
bottom to drain off the lye and wash water. The inside dimensions of 
this tank are: Length, 6 feet; breadth, 3 feet; depth, 1 foot 6 inches. 
Fifteen kilos of grain hulls can be readily handled in it at one time. In 
addition to the tank, a homemade filter press, for removal of the excess 
water after hydrolysis, and an eight-compartment special drying oven 
constituted the major portion of the equipment. 
The procedure in treatment of the hulls was as follows: An amount of 
sodium hydroxid equivalent in weight to eight times the amount of hulls 
used was made ready in the tank, the exact strength being adjusted by 
titration and addition of more NaOH or water as required. The desired 
amount of hulls was weighed out and transferred at once to the tank, 
where it was thoroughly mixed with the alkali by means of a wooden hoe. 
The strengths of sodium hydroxid used were 1, 1.5, and 3 per cent. The 
1.5 per cent strength is that employed by Beckmann. The 3 per cent 
strength, used with rice hulls only, was employed in order to ascertain 
whether it would have any more marked action on the very woody, gritty 
rice hulls than did the 1.5 per cent strength. The 1 per cent strength 
was used with the idea of economy in mind. The mixture was allowed 
to stand for three hours, with frequent stirring; the soda liquor was then 
drained off as completely as possible and the hulls thoroughly washed 
with cold water until the wash water no longer showed a pink tinge with 
phenolphthalein, about six changes of water being usually sufficient. 
The hulls were then transferred to the filter press, where the excess water 
was removed, and they were finally spread out in as thin layers as possi¬ 
ble in shallow galvanized pans and dried in the special steam oven. 
When dry they were bagged and stored until such time as the digestion 
experiments could be carried on, which, as a matter of fact, was almost 
immediately. 
As in all the digestion work done at this station, sheep were used, all 
the individuals employed being aged wethers well trained in the routine 
of the work. This is a detail of no small significance, as anyone can 
attest who has attempted work of this kind. The feeding trials were 
carried on in the usual manner, ample details of which are given in an 
earlier publication of this station (29). Two sheep were used through¬ 
out each trial. The hulls, both treated and untreated, were fed at the 
rate of 100 gm. 5 daily, along with a basal ration 6 7 of 500 gm. English hay, 
150 gm. gluten feed, 10 gm. salt, and water ad libitum. 
The hulls were mixed with the gluten feed, and no trouble was experi¬ 
enced in getting the sheep to eat them. No further preparation of the 
hulls was necessary except in the case of the rice hulls, which had to be 
ground before the sheep would eat thiem. 
Feeds and feces were submitted to the regular fodder analyses, accord¬ 
ing to the methods of the Association of Official Agricultural Chemists,? 
6 In the case of the untreated oat hulls and rice hulls, and the oat hulls and rice hulls treated with 1.5 per 
rent sodium hydroxid, the amount of hulls fed was 150 gm. . , ,. 
« The basal ration for the trials in which untreated oat hulls and oat hulls treated with 1.5 per cent sodium 
hydroxid were fed contained no gluten feed: otherwise it was identical withjihat jjiven above. 
7 Association of Official Agricultural Chemists, of - - - 
COMPILED BY THE COMMITTEE ON REVISION OF METHODS 
ington, D. C. 1920. 
OFFICIAL AND TENTATIVE METHODS OF ANALYSIS, AS 
Revised to Nov. 1 , 1919 - P • 7i, 72,97*98- Wash- 
