1are exposed before his eyes.
There are just as great differences in hills as
there are in mountains, yet the miner does not dig except in those situated
in mountainous districts, and even very rarely in those. It is however very
little to be wondered at that the hill in the Island of Lemnos was excavated,
for the whole is of a reddish-yellow colour, which furnishes for the inhabitÂ
ants that valuable clay so especially beneficial to mankind10. In like
manner, other hills are excavated if chalk or other varieties of earth are
exposed, but these are not prospected for.
there are in mountains, yet the miner does not dig except in those situated
in mountainous districts, and even very rarely in those. It is however very
little to be wondered at that the hill in the Island of Lemnos was excavated,
for the whole is of a reddish-yellow colour, which furnishes for the inhabitÂ
ants that valuable clay so especially beneficial to mankind10. In like
manner, other hills are excavated if chalk or other varieties of earth are
exposed, but these are not prospected for.
There are likewise many varieties of valleys and plains.
One kind is
enclosed on the sides with its outlet and entrance open; another has either
its entrance or its outlet open and the rest of it is closed in; both of these are
properly called valleys. There is a third variety which is surrounded on all
sides by mountains, and these are called convalles. Some valleys again,
have recesses, and others have none; one is wide, another narrow; one
is long, another short; yet another kind is not higher than the neighbouring
plain, and others are lower than the surrounding flat country. But the
miner does not dig in those surrounded on all sides by mountains, nor in those
that are open, unless there be a low plain close at hand, or unless a vein
of metal descending from the mountains should extend into the valley.
Plains differ from one another, one being situated at low elevation,
and others higher, one being level and another with a slight incline. The
miner should never excavate the low-lying plain, nor one which is perfectly
level, unless it be in some mountain, and rarely should he mine in the other
kinds of plains.
enclosed on the sides with its outlet and entrance open; another has either
its entrance or its outlet open and the rest of it is closed in; both of these are
properly called valleys. There is a third variety which is surrounded on all
sides by mountains, and these are called convalles. Some valleys again,
have recesses, and others have none; one is wide, another narrow; one
is long, another short; yet another kind is not higher than the neighbouring
plain, and others are lower than the surrounding flat country. But the
miner does not dig in those surrounded on all sides by mountains, nor in those
that are open, unless there be a low plain close at hand, or unless a vein
of metal descending from the mountains should extend into the valley.
Plains differ from one another, one being situated at low elevation,
and others higher, one being level and another with a slight incline. The
miner should never excavate the low-lying plain, nor one which is perfectly
level, unless it be in some mountain, and rarely should he mine in the other
kinds of plains.
With regard to the conditions of the locality the miner should
not contemplate mining without considering whether the place be
covered with trees or is bare. If it be a wooded place, he who digs there
has this advantage, besides others, that there will be an abundant supply of
wood for his underground timbering, his machinery, buildings, smelting,
and other necessities. If there is no forest he should not mine there unless
there is a river near, by which he can carry down the timber. Yet wherever
there is a hope that pure gold or gems may be found, the ground can
be turned up, even though there is no forest, because the gems need only
to be polished and the gold to be purified. Therefore the inhabitants of
hot regions obtain these substances from rough and sandy places, where
sometimes there are not even shrubs, much less woods.
not contemplate mining without considering whether the place be
covered with trees or is bare. If it be a wooded place, he who digs there
has this advantage, besides others, that there will be an abundant supply of
wood for his underground timbering, his machinery, buildings, smelting,
and other necessities. If there is no forest he should not mine there unless
there is a river near, by which he can carry down the timber. Yet wherever
there is a hope that pure gold or gems may be found, the ground can
be turned up, even though there is no forest, because the gems need only
to be polished and the gold to be purified. Therefore the inhabitants of
hot regions obtain these substances from rough and sandy places, where
sometimes there are not even shrubs, much less woods.
The miner should next consider the locality, as to whether it has a
perpetual supply of running water, or whether it is always devoid of water
except when a torrent supplied by rains flows down from the summits of the
mountains. The place that Nature has provided with a river or stream can
perpetual supply of running water, or whether it is always devoid of water
except when a torrent supplied by rains flows down from the summits of the
mountains. The place that Nature has provided with a river or stream can
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