■i04 Composition and Nuh-itivc Value of Straw. 
liaj. Oat-straw, so harvested, ought therel'ore to be as useful in 
repairing the waste of muscle of working oxen and horses as 
common hay. It is indeed much relished by animals, especially 
by working horses, who have good reasons for their predilec- 
tion, one no doubt being the larger proportion of Hesh-forming 
matters that it contains, and another probably its more succulent 
and palatable condition, 
2. The greater proportion of the albuminous or protein com- 
pounds exists in the green straw in a condition in which they 
are soluble in water, and therefore in all probability more easily 
digested than they are in an insoluble state. 
3. Towards maturity the amount of albuminous and nitro- 
genised compounds dwindles down to about one-half. Thus, 
whilst green straw contains 8J per cent, of nitrogenised matters, 
that which is fairly ripe contains only 4 per cent. The soluble 
and insoluble protein compounds likewise appear to diminish at 
precisely the same rate. 
In green straw we have, in round numbers, 5^ per cent, of 
soluble nitrogenized matters against 2"6 per cent, in the fairly 
riyie sample, and 3 per cent, of insoluble protein compounds 
against 1^ per cent. 
The question arises, what becomes of all the nitrogenised 
matter, which disappears with extreme rapidity when our cereal 
crops arrive at maturity? Although I have not made any special 
experiments with a view of ascertaining this point, it does not 
appear to me likely that this matter is all stored up in the grain ; 
and I have not much doubt that, as observed by Messrs. Lawes 
and Gilbert, a considerable loss of nitrogen takes place in the 
growth of corn-crops, which loss is particularly noticeable when 
the crop arrives at maturity. 
4. In over-ripe oat-straw a still further, though inconsiderable, 
diminution of nitrogenised matters took place. But whereas, in 
the two other samples, the soluble nitrogenised matter greatly 
preponderates over the insoluble, the reverse is the case in the 
over-ripe specimen. In this sample it will be seen that the 
insoluble protein compounds amount to 2 iV per cent, and the 
soluble to only 1 iV per cent. 
Over-ripe straw then is not only absolutely poorer in albu- 
minous or flesh-forming matters than fairly ripe samples, but it 
likev/ise contains these important constituents in a less soluble, 
and therefore less digestible, form. 
5. The proportions of oil in the three samples differ but little. 
G. Of sugar, gum, and other matters soluble in water, not less 
than 10 per cent, occurs in the green stiaw, as against 3 per cent, 
in the over-ripe straw. In the fairly ripe sample l()i> })er cent, 
of sugar, gum, t5cc., were found, or a proportion which exceeds 
