The British Press; or, Morning Literary Advertiser.
London, England, 1825-03-08 00:00:00

MEXICAN MINES.

We extract the following from the interesting pannshlgt
of Sir William Adams, on the teethe state of those mind :
" It may be almost difficult for a person not well informed on
the subject, to comprehend the vast produce of some of the Melia:on
mines, as there are no parallel examples of the kind in the world.
One of these, namely. the Videuctana, Baron Humboldt has very
minutely described in his work on New Spain. The Baal swag
this mine to be the richest mine of Mexico. It lies from Oghty to
an hundred leagues further in the interior than the city of Mexico,
on the mother vein of Guanawato. This mine, the Baron atTrwris,
produced as much silver is the your 1791 as was produced by the
whole kingdom of Peru that year, and that it yields seven time*
more metal than the mines of Freiberg, and one.half as much ra
the whole kingdom of Saxony ! ! He moreover adds, that the
amount of the sales of the raw ores at the pit's mouth (where, as in
Cornwall, they are sold weekly by auction), averaged, during
thirty-three years, from 1771 to 1304, the enormous sum of 883,31101-
per annum, while he also asserts that it " never yielded less eat
profit" during forty years, than from 82,306/. to 123,7 V/. per
annum. notwithstanding the excessive expenses incurred, and the
unscientific manner in which every operation its connected with the
mining department was conducted. Some years the net profits
amounted to 240,0001. This mine continued exceedingly rich up
to the period of the revolution in 1810, as is proved by official do-
cuments brought to this country, which state, that up to that
period it continued to produce ores to the amount of a million and a
half dollars per annum.
" The accounts which have reached this country from the min-
ing districts, through different channels, as well as the letters re
cently received from Mexico, fully confirm the favourable opinior.a
advanced by the writer, and it is publicly mentioned in the city
that they are now raising two thousand mule loads of ore per week,
from the upper works of the Valenciana mine, which quantity of
ore, calculated at the value of four ounces of silver per cwt. of Ore
(Humboldt's estimate), would give a produce exceeding 00X
weekly. Such being already the case, it is difficult to form any
accurate estimate of what will be the ysloe of the produce of this
aline (declared in a published letter of Captain Garby, the chief
miner sent out by the Anglo-Mexican Mine Company, to be more
valuable than all the mines of Cornwall united), when it is freed
from Its water, and in full work ; and when the very rich ores con-
tained in its colossal pillars, or supports, between the different
workings can be reached. These pillars are estimated by the best
Mexican judges to be worth 40,000,000 of dollars, or 8,000,0091.
sterling, even if sold at the pit's mouth ; but, front the information
received, it is probable that these enormous masses of rich ore
which constitute the pillars between the six or eight-and-twenty
horizontal tiers of workings in this mice, will produce eight or ten
times that amount, when converted by the improved systems of
smelting or amalgamation.
" Hence then, whenever the mine becomes exhausted of its MOP,
an immense prop.rty may be realised, by the entire removal of
these pillars ; while according to the opinions of Mr. Moyle and
Mr. Garby, two-thirds of them may, even now, be removed with-
out danger to the mine, by substituting props of wood, combined
with refuse stones, as is the practice in Cornwall under similar cit-
cumstaLces."

NORFOLK CIRCUIT.