Agricola, Georgius, De re metallica, 1912/1950

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1into a dish placed underneath to prevent any of the metal from falling to
the ground.
They break a hard vein loose from the footwall by blows with
a hammer upon the first kind of iron tool13, all of which are designated by
appropriate names, and with the same tools they hew away the hard hanging­
wall rock.
They hew out the hangingwall rock in advance more frequently, the
rock of the footwall more rarely; and indeed, when the rock of the footwall
resists iron tools, the rock of the hangingwall certainly cannot be broken unless
it is allowable to shatter it by fire.
With regard to the harder veins which are
tractable to iron tools, and likewise with regard to the harder and hardest
kind of hangingwall rock, they generally attack them with more powerful
iron tools, in fact, with the fourth kind of iron tool, which are called by their
appropriate names; but if these are not ready to hand, they use two or
three iron tools of the first kind together.
As for the hardest kind of metal­
bearing vein, which in a measure resists iron tools, if the owners of the
neighbouring mines give them permission, they break it with fires.
But if
these owners refuse them permission, then first of all they hew out the rock of
the hangingwall, or of the footwall if it be less hard; then they place timbers
set in hitches in the hanging or footwall, a little above the vein, and from
the front and upper part, where the vein is seen to be seamed with small
cracks, they drive into one of the little cracks one of the iron tools which
I have mentioned; then in each fracture they place four thin iron
blocks, and in order to hold them more firmly, if necessary, they place
as many thin iron plates back to back; next they place thinner iron
plates between each two iron blocks, and strike and drive them by
turns with hammers, whereby the vein rings with a shrill sound; and the
moment when it begins to be detached from the hangingwall or footwall
rock, a tearing sound is heard.
As soon as this grows distinct the miners
hastily flee away; then a great crash is heard as the vein is broken and torn,
and falls down.
By this method they throw down a portion of a vein weigh­
ing a hundred pounds more or less.
But if the miners by any other method
hew the hardest kind of vein which is rich in metal, there remain certain
cone-shaped portions which can be cut out afterward only with difficulty.
As
for this knob of hard ore, if it is devoid of metal, or if they are not allowed to
apply fire to it, they proceed round it by digging to the right or left, because
it cannot be broken into by iron wedges without great expense.
Meantime,
while the workmen are carrying out the task they have undertaken, the
depths of the earth often resound with sweet singing, whereby they lighten a
toil which is of the severest kind and full of the greatest dangers.
As I have just said, fire shatters the hardest rocks, but the method of its
application is not simple14. For if a vein held in the rocks cannot be hewn

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