therefore cannot be used for paint, but
burns freely in lamps and is useful for oiling machinery.

Among the various seeds used in the manufacture of oil-cake, flour of
linseed is the most important. Rape seed is also employed, but is
considered heating. In Lubeck, a marc, called dodder cake, is made
from the _Camelina sativa_. Inferior oil-cake is made from the poppy
in India. Cotton-seed cake has lately been recommended on account of
its cheapness, being usually thrown away as refuse by the cotton
manufacturers. It is extensively used as a cattle food, in an
unprepared state, in various parts of the tropical world, and to a
limited extent in this country.

The cost of seed, freight included, was 2d. per lb. from Charlestown
to Port Glasgow. Cotton oil-cake is now ordered at the same price as
linseed cake. The produce of oil-cake and oil from cotton seed, is two
gallons of oil to one cwt. of seed, leaving about 96 lbs of cake; 8
lbs. is the daily allowance for cattle in England.

Cotton seed oil, very pure, is manufactured to a considerable extent
at Marseilles, by De Gimezney, from Egyptian seed; and he received a
prize medal at the Great Exhibition.

Account of the export of linseed and rapeseed cakes from Stettin,
principally to England, in--

cwts.
1834 33,518
1835 27,038
1836 56,581
1837 70,643
1838 119,540
1839 115,416
1840 162,457
1841 143,816
1842 119,814

The quantity of oil-seed cakes imported into the United Kingdom was
in--

tons.
1849 59,462
1850 65,055
1851 55,076
1852 53,616

Cargoes of oil-cake, to the value of L22,207, were exported from the
port of Shanghae, in China, in 1849.

2,467 tons of oil-cake were brought down to New Orleans from the
interior in 1848, and 1,032 tons in 1849.

Seven samples of American oil-cake gave the following results:--

Oil 11.41
Water 7.60
Nitrogen 4.74
Ash 6.35

From the above figures, the scientific farmer will see that the manure
formed by 100 lbs. of oil-cake is more than that derived from 300 lbs.
of Indian corn. 300 lbs. of corn contain about l1/4 lbs. phosphoric
acid; 100 lbs. oil-cake contain about 21/2 lbs.

VOLATILE OR ESSENTIAL OILS occur in the stems, leaves, flowers and
fruit of many odoriferous plants, and are procured by distillation
along with water. They are c