manure, which is deserving attention, both because it is in itself
likely to prove a serviceable addition to the list of fertilizers
which may be advantageously employed, and because it may lead to the
use of similar substances, which are at present neglected, or thrown
aside as refuse.

The castor oil seed resembles in chemical composition the other oily
seeds. It consists of a mixture of mucilaginous, albuminous, and oily
matters; and the former two of these are identical in constitution and
general properties with the substances found in linseed and rape cake,
while the oil is principally distinguished by its purgative
properties. The cake obtained is in the form of ordinary oil-cake, but
is at once distinguished from it by its color, and by the large
fragments of the husk of the seeds which it contains. It is also much,
softer, and may be easily broken down with the hand. I have analysed
two samples of castor cake, stated to have been obtained by different
processes; and though I have not been informed of the exact nature of
these processes, I infer, from the large quantity of oil, that one
must have been cold-drawn. The first of the following analyses is that
of the sample which I believe the cold-drawn. It is the most complete
of the two, and contains a determination of the amount of oil. In the
other analysis this was not done, but there was no doubt on my mind
that its quantity was much smaller.

No. 1. No. 2.
Water 8.32 16.31
Oil 24.32 --
Nitrogen 3.05 3.35
Ash 7.22 4.95

The ash contains--
Siliccous matters 1.96 --
Phosphates 3.36 2.27
Excess of phosphoric acid 0.64 --

In order to give a proper idea of the value of this substance as a
manure, I shall quote here, for comparison sake, the average
composition of rape cake, as deduced from the analyses contained in
the Transactions of the Highland Society of Scotland:--

Water 10.68
Oil 11.10
Nitrogen 4.63
Ash 7.79
The ash contains--
Siliccous matters 1.18
Phosphates 3.87
Excess of phosphoric acid 0.39

It will be at once seen that there is a close general resemblance
between these two substances, although