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This gave them a button of impure lead,
which they subjected to what is called
cupellation. This rather grand word denotes a
very simple process. The button is placed
upon a little tiny saucer made of lime, and is
submitted to heat sufficient to melt the lead,
but not high enough to affect the silver,
should any be present. The lead soon begins
to melt, and, as it melts, it is sucked up by
the porous little saucer or cupel: it grows
smaller and smaller, until no lead remains,
and in its place is a little brilliant speck, far
brighter than the boiling lead. The cupel is
then removed from the fire, and as it cools
the redhot spark cools too, and you have a
homœopathic globule of silver, very much like
one of those small pills that druggists delude
smokers into buying to take away the smell
of the fragrant weed. The operation, as I
have said, is very simple, and is the ordinary
mode of procuring silver from the ore.
Analyses are being made in this way, every
day, at the Mint. When the presence of
silver is doubtful, the work is most exciting.
I saw an English ore so tested the other day,
and sure enough, after a few minutes of
anxious watching, shone forth a bright spark
about the size of a pin's head, for which our
eyes were longing. The ore proved a very
rich one, and we shall most likely soon hear
more about it.

But we must not forget our French friends.
Again and again they repeated the experiment
with the same success. Then they sat
down and made the calculation that a cubic
mile of ocean contains two pounds and three-
quarters weight of silver. After this, they
made another series of experiments: they
gathered seaweeds, preferring those known
to botanists as fuci: because, as those plants
have no roots to insert into the rocks, they
must derive all their aliments from the sea.
These they analysed, and found them twenty-
six times richer in silver than the water
itself.

The results attracted the attention of an
English chemist, Mr. Frederick Field, who is
engaged in assaying silver in Chili; they in-
duced him to commence a course of experiments
upon the copper or yellow metal with
which the hulls of vessels are sheathed. His
knowledge of chemistry told him that if the
sea contained silver, he would in all
probability find the metal on the bottoms of
vessels that had been at sea. He soon had
an opportunity of testing the correctness of
his surmise. The Ana Guimaraens, a large
vessel under the Chilian flag, was hauled
down to be repaired near Coquimbo, where
Mr. Field resides. The ship had been seven
years at sea, and trading the whole of the
time in the Pacific Ocean; so that if silver
existed in any ship's bottom it certainly
would in the Ana Guimaraens. A few ounces
of the metal sheathing were taken, and, after
a careful analysis, Mr. Field obtained from
five thousand grains a trifle more than two
grains of silver, which is equal to one pound
one ounce two pennyweights fifteen grains in
the ton. There was no yellow metal on
board the ship by which a comparison
could be made with that which had been
exposed to the salt-water. But, shortly
afterwards, another vessel came into dock, and
from her cabin a piece of metal was taken
which had never been exposed to sea-water,
and another piece of equal weight was
removed from the hull, which had been three
years afloat. The metal from the hull yielded
eight times as much silver as that taken from
the cabin. Similar comparative analyses
were made on other vessels, and a difference
between the two metals was invariably
found: the difference varying according to
the length of time the ship had been at
sea. In those ships that had been the
shortest time at sea the difference was least,
and vice versâ.

But, why should there be any silver in the
brass and copper used in the cabins? Well,
it appears that in these metals there is
generally a little silvertwo or three penny-
weights per ton; and beyond this, Mr. Field
accounts for it from the employment of masses
of metal melted down from old sheathings
which derive their silver from former voyages.
One other experiment Mr. Field is at present
carrying out. He has granulated some very
pure coppera portion is reserved in a bottle
to be compared at a future period with the
other portion, which is floating in a wooden:
box, perforated on all sides, a few feet below
the surface of the Pacific. When a good-
humoured captain puts into Coquimbo, he
takes the box in tow, and drags it at the
stern of his vessel up and down the coast
of Chili. Just as you have tried to catch
a mackerel with a mackerel's tail, so is Mr.
Field trying to catch silver with his copper
bait.

The curious discovery of sea-water silver
gives rise to one or two questions. Where,
for instance, does the silver come from?
Has it been extracted from the earth by
artificial means, the waste of man's diggings,
borne to the bosom of ocean by rivers,
which, like giant arteries, burst from the
heart of the earth? It could scarcely be
that man, avaricious man, could have let two
millions of tons of silver so slip through his
fingers. No! we may acquit the world of so
egregious a blunder. That the presence of
silver in the sea is more ancient than human
folly or cupidity, M. Durocher and his friends,
who first called attention to the subject, have
proved by procuring the precious metal from
crystals of rock salt which had been deposited
anterior to the existence of man upon this
earth.

One experiment leads to another. If the
sea could be made to yield silver, where
might not the metal be found? The wood of
the oak, birch, beech, hornbeam, aspen, apple,
and ash, grown at long distances from the