20 
The Colorado Experiment Station. 
obtained by extracting air-dried bay with those obtained from the 
same hay dried in the water oven, also in hydrogen and have seldom 
found so large a variation that it was of any practical significance. 
The maximum amount of nitrogen found in the ether extracts of 
the three hays, alfalfa, timothy and native hay, was contained in the 
extract from the native hay which contained 0.007 per cent.; that 
from the timothy contained nitrogen equal to 0.0033 per cent, and 
that from the alfalfa 0.0032 per cent., calculated on the air-dried 
hay. The largest one of which corresponds to less than 0.05 per 
cent, of proteids. 
§55. The weight of the dried ether extracts from these three 
hays varied from 0.5 to 0.75 grams from which it is evident that 
the coloring matters in these hays must be poor in nitrogen. 
§56. If we assume that the nitrogen in these ether extracts 
is present as proteid nitrogen there would be in that from the native 
hay approximately 0.05 per cent., a quantity which we can disregard 
in ordinary work but this is twice as large as the amount found in 
either of the other two hays. 
§57. In regard to the sulfur in alfalfa, the question has fre¬ 
quently suggested itself whether it belonged mostly to the proteids 
or whether it was present in combination, as sulfuric oxid, probably 
forming calcic sulfate. Wishing to answer this question in con¬ 
nection with the proteids, we digested a quantity of hay with dilute 
hydrochloric acid and washed it thoroughly. The sulfuric acid 
was then precipitated as baric sulfate and weighed after purifica¬ 
tion. The sulfur present in the hay as sulfuric acid amounted to 
0.68 per cent. The total sulfuric acid estimated from that found in 
the ash, allowing a loss of two per cent, in incineration, was 0.94, 
leaving sulfur equivalent to 0.26 per cent, of sulfuric acid as pro¬ 
teid sulfur. 
§58. Corn fodder treated in the same manner did not show 
the presence of any sulfuric acid and the sulfur is probably present 
as proteid sulfur and not in the form of sulfates. 
§59. In the following statements, the proteids, respectively 
the nitrogen calculated as proteids, soluble in 80 per cent, alcohol 
included the nitrogen soluble in the ether which, as we have just 
seen, is a very small amount, not more than 0.05 per cent. 
§60. The coefficients of digestion for the proteids contained 
in the various extracts of alfalfa hay:— 
