ectively five
and six years. They were fed--firstly, upon hay alone; secondly, upon
hay and rye-straw; thirdly upon hay and the sawdust of poplar wood,
which had been exhausted with lye (to induce the sheep to eat the
sawdust, it was found necessary to mix through it some rye-bran and a
little salt); fourthly, hay and pine-wood sawdust, to which was added
bran and salt; fifthly, spruce sawdust, bran and salt; sixthly, hay,
pulp of linen rags (from the paper-maker), and bran. The experiments
were carried on from July till November, excepting a short time, during
which the animals were turned out on pasture-land, to recover from the
injurious effects of the fifth series of experiments--produced probably
by the resin of the spruce. The animals, together with their food,
drink, and egesta, were weighed daily. The amount of cellulose in the
food was determined, and the proportion of that substance in the egesta
was also ascertained; and as there was a considerable discrepancy
between the two amounts, it was evident that the difference represented
the weight of the cellulose assimilated by the animals. In this way it
was ascertained that from 60 to 70 per cent. of the cellulose of hay,
40 to 60 per cent. of the cellulose of straw, 45 to 50 per cent. of the
cellulose of the poplar wood, 30 to 40 per cent. of the cellulose of the
pine, and 80 per cent. of the cellulose of the paper pulp was digested.

In stating the results of his analyses of the straws, Professor Voelcker
sets down as "digestible" that portion of the cellulose which he found
to be soluble in dilute acids and alkaline solutions; but he admits that
the solvents in the stomach might dissolve a larger amount. The results
of the experiments of Stoeckhardt and Sussdorf prove that 80 per cent. of
the cellulose of paper (the altered fibre of flax) is assimilable, and
it is, therefore, not unreasonable to infer that the cellulose of a more
palatable substance than paper might be altogether digestible.

The facts which I have adduced clearly prove that the straws of the
cereals possess a far higher nutritive power than is commonly ascribed
to them; that when properly harvested they contain from 20 to 40 per
cent. of undoubted nutriment; and lastly, that it is highly probable
that their so-called indigestible woody fibre is to a great extent
assimilable.

The composition of cellulose is nearly, if not quite, identical with
that of starch, and it may therefore be assume