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which purpose the oil should always be obtained 
by cold pressing. The cake remaining after the 
expression of the oil is poisonous and can therefore 
only be used as a fertiliser. 
The present prices (Sept. 1923) are as follows: 
Castor seed £19 per ton, Castor oil £49 — £53 per ton. 
Candlenut. ( Aleurites triloba syn. A. moluccana). 
This is a tall-growing tree attaining 
a height of from 40 to 50 ft. The fruits contain 
hard-shelled nuts, the kernels of which have an oil 
content of about 62 per cent., equivalent to about 
19 per cent, on the nut. 
The oil, which is obtained by expression, is a drying 
oil, somewhat inferior to linseed, and can therefore 
be used for more or less the same purposes, such as 
paints, varnishes and soft soaps. 
This crop has so far only been cultivated in this 
country on an experimental scale and few details 
as to its possibilities are available. 
Rubber. ( Hevea Brasiliensis ) . — This tree is 
too well-known to require description. 
The seed kernels contain about 42 per cent, of oil, 
equivalent to about 24 per cent, on the whole seed. 
Like candlenut, this oil belongs to the drying class, 
being also inferior to linseed ‘oil. The seed contains 
an active fat-splitting enzyme or non-organised 
ferment and, to obtain a high grade oil, the seeds 
should be pressed either as soon as possible after 
collection or treated in some way to prevent the 
development of this free fatty acid. It might be 
mentioned that seed is only obtainable during about 
3 months of the year. The oil cake appears to have 
considerable possibilities as a cattle food. 
