en to the proper cross dimensions, by means
of circular saws of different shapes. They are afterwards drilled with
great accuracy by a machine; rivetted to the blade; and finally
smoothed and polished. We believe that this branch of industry alone
gives employment to about 500 persons in Sheffield. Combs are seldom
made of any ivory but Indian, and their mode of manufacture we had
recently occasion to describe.[4] A large amount of ivory is consumed
in the backs of hairbrushes; and this branch of the trade has recently
undergone considerable improvements. The old method of making a
tooth-brush, for example, was to lace the bristles through the ivory,
and then to glue, or otherwise fasten, an outside slab to the brush
for the purpose of concealing the holes and wire-thread. This mode of
manufacture has been improved on by a method of working the hair into
the solid ivory; and brushes of this description are now the best in
the market. Their chief excellence consists in their preserving their
original white colour to the last, which is a great desideratum.
Billiard-balls constitute another considerable item of ivory
consumption. They cost from 6s. to 12s. each; and the nicety of our
ornamental turning produces balls not only of the most perfect
spherical form, but accurately corresponding in size and weight even
to a single grain.

The ivory miniature tablets so much in use, and which are so
invaluable to the artist from the exquisitely delicate texture of the
material, are now produced by means of a very beautiful and highly
interesting chemical process. Phosphoric acid of the usual specific
gravity renders ivory soft and nearly plastic. The plates are cut from
the circumference of the tusk, somewhat after the manner of paring a
cucumber, and then softened by means of the acid. When washed with
water, pressed, and dried, the ivory regains its former consistency,
and even its microscopic structure is not affected by the process.
Plates thirty inches square have been formed in this way, and a great
reduction in price has thus been effected. Painting on ivory, we may
add, was practised among the ancients.

Mr M'Culloch and other statistical writers predict the speedy
extinction of the elephant, from the enormous consumption of its
teeth; and curious calculations of the number of these animals
annually extirpated to supply the English market alone are now getting
somewhat popular. For example: 'in 1827 the customs-duty on