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Darwin, Charles, 1809-1882

"The Voyage of the Beagle"

There can be no
doubt that the chemical action, already mentioned, each time
liberates fresh gold from some combination. The discovery of a
method to effect this before the first grinding would without doubt
raise the value of gold-ores many fold. It is curious to find how
the minute particles of gold, being scattered about and not
corroding, at last accumulate in some quantity. A short time since
a few miners, being out of work, obtained permission to scrape the
ground round the house and mill; they washed the earth thus got
together, and so procured thirty dollars worth of gold. This is an
exact counterpart of what takes place in nature. Mountains suffer
degradation and wear away, and with them the metallic veins which
they contain. The hardest rock is worn into impalpable mud, the
ordinary metals oxidate, and both are removed; but gold, platina,
and a few others are nearly indestructible, and from their weight,
sinking to the bottom, are left behind. After whole mountains have
passed through this grinding mill, and have been washed by the hand
of nature, the residue becomes metalliferous, and man finds it
worth his while to complete the task of separation.


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