AGRICULTURE AND DENDROLOGY. 
bag* were emptied several times a day into a capacious beaker 
and kept covered. Every 24 hours, in the morning, before 
giving - the food, the fæces were weighed, well mixed and an 
aliquot part usually 1/10, taken for the analysis. Besides 
this the animals were weighed every morniug, before they 
were fed. The feeding boxes just described have the 
advantage that they prevent the scattering of food almost 
completely, preclude entirely that food comes in contact 
with excreta, admit of a complete collection of the urine, 
and afford the greatest cleanliness during the whole trial. 
As ruminants retain the food several days in the body, 
before the undigestible portions of it are ejected, it is 
necessary to continue with the feeding of the ration under 
experiment for at least 5-6 days before samples of excreta 
are taken for the analysis. The digestion experiments are 
accordingly divided into a preliminary or preparatory 
period of at least 6 days and a main period of 6-8 days. 
We commenced the main period only after the animals had 
for 6-8 days consumed their ration either totally, or at least 
so uniformity that the uneaten residues did not vary greatly 
from day to day. The residues of the ration, and the 
fæces, were collected only during the main period, 
aliquot portions of each substance were then taken every 
day, dried in a steam bath and afterwards mixed and 
analyzed. Of the food samples for analysis were collected 
three times, viz. 2 days before commencing the main period, 
4 days after this time, and 3 days before closing the trial. 
The fodders, uneaten residues and fæces were analyzed 
in the usual way. We determined the dry matter by 
drying the substance to constant weight at 100-110° C, the 
total nitrogen until 1886 by Will-Varrentrapp’s method 
and thereafter by that of Kjeldahl, the albuminoid nitrogen 
by precipitation with hydrated cupric oxide, the crude fat 
by extraction of the dried substance with absolute ether, 
the crude fibre by Henneberg’s acid and alkali method, 
