“Through dark retreats pursue the winding ore,
Search nature’s depths, and view the boundless store;
The secret cause in tuneful numbers sing,
How metals first were framed, and whence they spring:
Whether the active sun, with chymic flames,
Through porous earth transmits his genial beams
With heat impregnating the womb of night
The offspring shines with his paternal light:
Or whether, urged by subterraneous flames,
The earth ferments and flows in liquid streams;
Purged from their dross, the nobler parts refine,
Receive new forms, and with new beauty shine:
Or whether by creation first they sprung,
When yet unpoised the world’s great fabric hung:
Metals the bases of the earth were made,
The bars on which its fixed foundation’s laid:
All second causes they disdain to own,
And from the Almighty’s fiat sprung alone.”
The transition from the caverns and caves of the earth, to its MINES,
and the various metals and gems they contain, is both natural and easy;
and having dwelt on the former, we propose next to advert to the latter.
By the word “_mines_” we understand those excavations, in which metals,
minerals and precious stones are sought and found; and according to the
substances which they yield they are variously spoken of as “gold
mines,” “silver mines,” “lead mines,” &c., &c. The richest and most
celebrated gold and silver mines are those of Mexico and Peru, in South
America, and those lately discovered in California and Australia. Iron
mines are more abundant, or at least more abundantly worked, in Europe
than elsewhere, though the rapid increase of iron mining in the United
States gives promise that our country may in this respect some day rival
the old world. Copper mines have been found chiefly in England, Sweden
and Denmark; and of late years copper has been found to be abundant in
the region of our northern lakes. Lead and tin mines are numerous in
England, the latter chiefly in the county of Cornwall; and lead is also
found in abundance in the United States. Quicksilver mines abound
principally in Hungary, Spain, Friuli, in the Venetian territories, and
in Peru. Diamond mines are mainly in Brazil, and some in the East
Indies; and salt mines are in Poland.
To explain the structure of mines, it should be observed that the
internal parts of the earth, as far as they have been investigated, do
not consist of any one uniform substance, but of various strata, or beds
of substances, extremely different in their appearances, specific
gravities and chemical qualities, one from another. Neither are these
strata similar to each other, either in their nature or appearance, in
different countries; insomuch that, even in the short extent of half a
mile, sometimes, the strata will be found quite different in one from
what they are in another place. As little are they the same either in
depth or solidity. Innumerable cracks and fissures are found in all of
them; and these again are so entirely different in size and shape, that
it is impossible to form any inference from what may have been met with,
relative to that which remains to be explored.
In Cornwall, the most common opinion entertained by the miners, is, that
crude and immature minerals nourish and feed the ores with which they
are intermixed in the mines; and that the minerals themselves will, in
process of time, be converted into ores productive of those metals to
which they have the nearest affinity, and with which they are most
closely intermingled. And a distinguished professor, who is familiar
alike with geology, chemistry and mineralogy, after visiting the mining
districts of California, has given it as his opinion, that gold is
constantly being formed there, by some powerful agency of nature which
is still and steadily at work. And as a somewhat kindred view, Mr.
Price, in his mineralogy of Cornwall, thinks it is most reasonable to
conclude, that metals were made and planted in veins, at, or very soon
after, the creation of the world; but that, in common with all other
matter, they are subject to a degree of fluctuation, approaching to, or
receding from, their ultimate degree of perfection, either quicker or
slower, as they are of greater or less solid and durable frame and
constitution. He supposes in every metal a peculiar magnetism, and an
approximation of particles of the same specific nature, by which its
component principles are drawn and united together; more particularly
the matters left by the decomposition of the waters passing through the
contiguous earths or strata, and deposited in their proper nidus or
receptacle, until, by the accretion of more or less of its homogeneous
particles, the metallic vein may be denominated either rich or barren.