Agricola, Georgius, De re metallica, 1912/1950

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    <archimedes>
      <text>
        <body>
          <chap>
            <p type="main">
              <s>
                <pb pagenum="121"/>
              it is on the sides they break it with hammers. </s>
              <s>Thus broken off, the rock
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              tumbles down; or if it still remains, they break it off with picks. </s>
              <s>Rock
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              and earth on the one hand, and metal and ore on the other, are filled into
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              buckets separately and drawn up to the open air or to the nearest tunnel.
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              </s>
              <s>If the shaft is not deep, the buckets are drawn up by a machine turned by
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              men; if it is deep, they are drawn by machines turned by horses.</s>
            </p>
            <p type="main">
              <s>It often happens that a rush of water or sometimes stagnant air hinders
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              the mining; for this reason miners pay the greatest attention to these
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              matters, just as much as to digging, or they should do so. </s>
              <s>The water of the
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              veins and stringers and especially of vacant workings, must be drained out
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              through the shafts and tunnels. </s>
              <s>Air, indeed, becomes stagnant both in
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              tunnels and in shafts; in a deep shaft, if it be by itself, this occurs if it is
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              neither reached by a tunnel nor connected by a drift with another shaft;
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              this occurs in a tunnel if it has been driven too far into a mountain and no
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              shaft has yet been sunk deep enough to meet it; in neither case can the
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              air move or circulate. </s>
              <s>For this reason the vapours become heavy and
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              resemble mist, and they smell of mouldiness, like a vault or some under­
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              ground chamber which has been completely closed for many years. </s>
              <s>This
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              suffices to prevent miners from continuing their work for long in these places,
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              even if the mine is full of silver or gold, or if they do continue, they cannot
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              breathe freely and they have headaches; this more often happens if they
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              work in these places in great numbers, and bring many lamps, which then
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              supply them with a feeble light, because the foul air from both lamps and
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              men make the vapours still more heavy.</s>
            </p>
            <p type="main">
              <s>A small quantity of water is drawn from the shafts by machines of
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              different kinds which men turn or work. </s>
              <s>If so great a quantity has flowed
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              into one shaft as greatly to impede mining, another shaft is sunk some
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              fathoms distant from the first, and thus in one of them work and labour are
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              carried on without hindrance, and the water is drained into the other, which
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              is sunk lower than the level of the water in the first one; then by these
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              machines or by those worked by horses, the water is drawn up into the drain
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              and flows out of the shaft-house or the mouth of the nearest tunnel. </s>
              <s>But
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              when into the shaft of one mine, which is sunk more deeply, there flows all
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              the water of all the neighbouring mines, not only from that vein in which
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              the shaft is sunk, but also from other veins, then it becomes necessary for a
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              large sump to be made to collect the water; from this sump the water is
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              drained by machines which draw it through pipes, or by ox-hides, about
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              which I will say more in the next book. </s>
              <s>The water which pours into the
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              tunnels from the veins and stringers and seams in the rocks is carried
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              away in the drains.</s>
            </p>
            <p type="main">
              <s>Air is driven into the extremities of deep shafts and long tunnels by
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              powerful blowing machines, as I will explain in the following book, which
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              will deal with these machines also. </s>
              <s>The outer air flows spontaneously into
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              the caverns of the earth, and when it can pass through them comes out again.
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              </s>
              <s>This, however, comes about in different ways, for in spring and summer it
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              flows into the deeper shafts, traverses the tunnels or drifts, and finds its way </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>
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