Report of the Assistant Chemist.* 
THE RELATIVE DIGESTIBILITY OF FEEDING STUFFS. 
During the past year a few experiments have been performed to: 
determine the relative digestibility of the albuminoids of some of 
our feeding-stuffs, also for comparing the relation of artificial with 
actual digestion, and to test the efficiency and ease of the following 
methods. 
Stutzer’s methodt was the first used. This consists of using a di- 
gestion fluid prepared from a hog’s stomach. 
A digestion fluid was also used prepared from commercial scale 
pepsin.{ ‘lhe latter solution is less difficult to prepare, much easier 
of use, and with me gave more uniform results than did Stutzer’s 
method. | 
The Pepsin method. 
A muriatic acid solution of .2 per cent. strength was made and to 
each liter of this wasadded 5 grams of pepsin. Fresh solutions were 
made for each test. \ 
The substance to be digested was thoroughly comminuted as for a 
chemical analysis. 1 or 2 grams were taken according to richness 
in nitrogen. 
The substance to be examined was placed in an Erlenmeyer flask, 
and when the solution from a hog’s stomach was used 250cc were 
taken, when the pepsin solution was used 150cce. Once in two hours 
1 gram of HCl. was added until the solution contained .7 grams, 
The flasks were set in a water bath heated at from 38° to 42° OC. for 
14 hours; then allowed to cool down during the night and on the fol- 
lowing day the heating was continued for six hours. They were 
then filtered, thoroughly washed with water until free from any 
traces of acid, then with alcohol, and the contents of the filter trans- 
ferred to a nitrogen flask and dried at 100° ©. 
The nitrogen in the undigested residue was then determined by 
Kjeldahl’s method. 
In table I are given the analyses of the substances examined, water 
free, and table II and III contain the data obtained from the exper- 
iments. 
*K. F. Ladd. 
+Journal fiir Landwirthschaft 1880 page 195; also Report of Maine State Col- 
lege 1883. 
{Manufactured by Henry Thayer & Co. 


