A crane for raising weights, on an entirely new principle--that of the
application of the lever, assisted by wedges, instead of the usual
plan of wheel and pinion, for multiplying power--has recently been
constructed at the West India Docks. The power of two men, with the
patent crane, is stated to be capable of lifting from 2-1/2 to 3 times
the weight lifted through the same space in a given time, by the best
constructed cranes on the old principle of wheel machinery.

_Etching on Ivory_.

The usual mode of ornamenting ivory in black, is to engrave the pattern
or design, and to fill up the cavities thus produced with hard black
varnish. Mr. Cathery has much improved and simplified the process, by
covering the ivory with engraver's varnish, and drawing the design with
an etching needle; he then pours on a menstruum, composed of 120 grains
of fine silver, dissolved in an ounce measure of nitric acid, and
diluted with one quart of pure distilled water. After half an hour, more
or less, according to the required depth of tint, the liquor is to be
poured off, and the surface is to be washed with distilled water, and
dried with blotting paper. It is then to be exposed to the light for
an hour, after, which the varnish may be removed by oil of turpentine.
The design will now appear permanently impressed on the ivory, and of
a black or blackish brown colour, which will come to its full tint after
exposure for a day or two to the light. Varieties of colour may be given
by substituting the salt of gold, platina, copper, &c. for the solution
of silver.--_Trans. of the Society of Arts._

_Geology._

Among the fossil bones lately dug from under the lava of the mountain
of Boulade, in the neighbourhood of Issoire, in France, none have been
discovered belonging to the human body. The same is the case in the
other mountains of the vicinity. But, although there are no human bones,
in several places, and especially in the mountain of Boutaresa, (which
is not far from the mountain of Boulade,) pieces of wood have been
discovered, buried under the ancient lava, which observers worthy of
credit declare seem to have been fashioned by the hand of man, and to
have been cut with a hatchet, although rudely, and as might be expected
in the infancy of the arts. Did man exist then, at that remote period
when elephants, lions, and tapirs, lived in Europe, with rein-deer and
bears? This is an exceedingly difficult question, and one which hit