On the Composition of a Crop of Hay. 103 
albuminoids—the two most valuable constituents of hay—than the 
meadow hay referred to. Ifwe compare the composition of this 
melic grass hay, when completely dried, with that of good meadow 
hay (also assumed to be free from water) it will be seen that with 
the exception of digestible non-nitrogenous substances, it com- 
pares favourably with the latter. 
Composition of the Hay of Purple Melic Grass (dry weight). 
100 parts contained— 
Oil, 5 : C : : : 3°75 
Albuminoids, . - : 10°40 
Non-nitrogenous soluble jabeien de A é 41°64 
Woody fibre, . 5 . - - 43°36 
Mineral matter (Ash), . ° é - 0°85 
100.00 
From the published results of a large number of analyses of 
meadow hay, the average composition of that article when dried 
at 100° centigrade appears to be as follows :— 
Composition of dried oi. per 100 parts. 
Fats, : ‘ Pete RO 3°30 
Albuminoids, , - —s 10:90 
Digestible non- rien artstaibens - ° 48°25 
Woody fibre, : ° a - 2 30°35 
Mineral matter (Ash), . - S c 7°20 
100:00 
The remarkable points in the composition of the purple melic 
grass hay are—firstly, the unprecedentedly small amount of ash 
which it contains, and secondly the almost complete absence of 
silica from its ash. Silica constitutes a large proportion of the 
mineral matter found in the external layers of the stems of the 
cereals, and is still more abundant in the mineral matter found in 
their leaves. In the grasses of every kind there is also found a 
decided amount of silica, usually about one-third of the total 
weight of ash. 
It is, however, very probable that silica is not an essential 
constituent of the ash of the cereals or other grasses. Knop and 
Sachs have grown to full development, maize plants in soils des- 
titute of silica ;.and similar experiments have been made with oats, 
