The Sun.
London, England, 1852-10-26 00:00:00

QUARTZ CRUSHING IN CALIFORNIA.

By the last advices from San Francisco, bearing date
the 31st August, it appears that the most remarkable
feature at present to be fonnd in the gold-producing
interests of that country is the great and constantly in-
creasing use of quartz-crushing engines. So short a
time has elapsed since gold was first discovered in such
hitherto unknown quantities, that it is easy to recal to
mind the various slow and progressive steps of science
in aiding the unpractised efforts of the minor in these
remote but fortunate regions. At first the roughest and
most common implements were employed in the reduc-
tion of the rock ; afterwards came the use of quick-
silver ; then the amalgamator, wherein this metal was
applied upon new principles ; and, lastly, great
crushing-mills have been brought into operation ;
which have considerably increased the yield of
gold. Some of the largest of these are endowed with
an energy which enables them to reduce to powder from
40 to 45 tons of rock per diem. Machines of this size
commonly employ from 20 to 24 men. The largest to
be mat with are about Nevada, in which region, when
fortune is occasionally propitious, the amounts of gold
extracted are almost incredible. On one occasion, after
a 48 hours' trial, ono of these mills turned out an
amount of gold equal in value to 6,400 dols. This re-
sult was said to have been a larger yield than the mill
had before given, though it had been worked on the
same spot over six weeks ; and it was partly due to the
crushing power of the mill itself, and partly to the use
of a new amalgamator, numbers of which have been in-
vented lately, and have attained a high pitch of per-
fection. It is impossible to read these accounts from
California without feeling that even now we are
only on the threshold of that mine of wealth which
will presently be developed under further and more
improved appearances of science. The quamity of
rock crushed by the mills above described is defi-
nitely stated, but the number of horse-power employed in
the operation is not named. We are only able to form
is rough idea of the power from the context; and the
fact that they are spoken of as " great" crushing mills,
and that one of the "largest" reduces to powder from 40
to 45 tons of rock per diem, induces us to suppose them
of no ordinary size, averaging, perhaps, from 20 to 60
horses. Such ponderous anti expensive machinery as
this cannot long hold possession of the gold districts;
they must soon give way before more portable and effec-
tive contrivance. In a trial made a few days since with
one of Bagg's new patent steam-stamps (and upon the
accuracy of our statement our readers may rely), no less
than 40 tons of coarse metal were crushed by a small
4-horse engine in 12 hours, though the steam entering
the cylinder was considerably less than the power of two
horses; 26 tons out of this quantity were reduced to a fine
powder, and carried at once to the calcining furnaces;
the remaining 14 tons were broken by the engine into
small pieces, the size of a walnut, and wero passed
through a pair of rolls, in order to afford a com-
parison of effect. Although the rolls were work-
ing with a power of six horses, and that the metal
was half crushed when delivered to them, they were
unable to dispose of the 14 tons within the same period
of time-12 hours ! These facts speak for themselves,
and will, doubtless, have an effect upon those who are
now expending large sums in the purchase of crushing
machinery of a more antiquated and less effective cha-
racter. One of the principal gold companies. who have
recently adopted the new patent stamps, will effect, ac-
cording to their own calculation, a saving of many thou-
sand pounos per annum, in dispensing entirely with the
enormous amount of hand labour now required for re-
ducing the large blocks of quartz to a a!ze sufficiently
smell for the ordinary stamp heads.
We also observe that one of Mr. Begge's engines is
advertised in another column for forthcoming exhibition
in London; and the fact that it is to be erected and
brought into practical operation at the now reduction
works of Messrs. Johnson and Matthey, at Millwalf,
would seem to afford proof of the estimation in which
its capabilities and usefulness are regarded by men of
the highest practical standing in the mining world.
In addition to these improvements for reducing the
rook to powder, we happen to bo ourselves cognizant of
a new and most effective invention for the extracAon of
the gold therefrom, the particulars of which will in due
time be made pnbl c. What effect these advances in
science will exercise upon the gold-producing districts of
California and Australia it is no very difficult matter to
prognosticate.—Mining Journal of Saturday.