Composition mul Nutritive Value of Strair. 
095 
Tlie asli of wheat-stniw, it will be seen, is very rich in silica 
— a constituent found in the straw of' all cereals in preponderating 
proportions. The amount of phosphoric acid and of potash is 
not large. The percentage of ash in wheat-straw varies exceed- 
ingly ; on an average it amounts to about 4|- per cent., but I have 
found it as low as 21- per cent. When I first met Avith this 
small percentage I took the precaution of repeating tlie deter- 
mination, and obtained from each trial closely agreeing results. 
It is worthy of remark that the straw in question was by no 
means weak, but as stiff as could be desired. It may therefore 
be doubted whetlicr the weakness of straw arises, as is generally 
assumed, from a deficiency of mineral matter, more especially of 
silica. 
This is a subject well deserving further investigation, which I 
hope to take up at a future period. But wiiilst reserving for 
future discussion tlie causes of weakness of straw, I cannot refrain 
from stating in passing that I have never met with a single 
instance in which the application of silicate of soda to wheat has 
had the slightest effect upon the crop ; and that therefore, as far 
as my practical experience extends, I am bound to say that sili- 
cate of soda does not answer the purpose for which its use has 
been suggested, viz., that of strengthening the straw of wheat, 
oats, and barley. 
Wheat-Stubble. 
Although wheat-stubble is not used for feeding purposes, its 
analysis may here find a place, for it may be useful to compare 
the composition of stubble with that of wheat-straw. 
The sample from which the following analysis was made was 
gathered on a dry day in the middle of December, from a field 
of the College Farm, Cirencester. Examined directly afterwards 
it was found to contain 17^ per cent, of moisture, and was thus 
drier than wheat-straw before stackins". This stubble contained 
in 100 parts : — 
General Composition. 
Moisture , 17-fi6 
Substances soUible in water 5-83 
Substances insoUible in water 76-51 
100-00 
Detailed Composition. ■ 
Water 17-GG 
Oil -42 
* Albuminous compounds 2 '94 
Extractive matters (soluble in water) .. .. 5-01 
Crude woody fibre 71 "04 
Mineral matters (asb) 2-93 
*Containing nitrogen 
VOL. XXII. 
100-00 
-47 
2 E 
