Agricola, Georgius, De re metallica, 1912/1950

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    <archimedes>
      <text>
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            <p type="caption">
              <s>
                <pb pagenum="520"/>
              the other on the left. </s>
              <s>Finally, outside the hearth is the receiving-pit, which
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              is a foot wide and three palms deep; when this is worn away it is restored
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              with lute alone, which easily retains the lead alloy.</s>
            </p>
            <p type="main">
              <s>If four liquation cakes are placed on the plates of each furnace, then the
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              iron blocks are laid under them; but if the cakes are made from copper
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              “bottoms,” or from liquation thorns, or from the accretions or “slags,” of
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              which I have partly written above and will further describe a little later,
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              there are five of them, and because they are not so large and heavy, no blocks
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              are placed under them. </s>
              <s>Pieces of charcoal six digits long are laid between the
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              cakes, lest they should fall one against the other, or lest the last one should
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              fall against the wall which protects the third long wall from injury by fire. </s>
              <s>In
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              the middle empty spaces, long and large pieces of charcoal are likewise laid.
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              </s>
              <s>Then when the panels have been set up, and the bar has been closed, the
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              furnace is filled with small charcoal, and a wicker basket full of charcoal is
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              thrown into the receiving-pit, and over that are thrown live coals; soon
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              afterward the burning coal, lifted up in a shovel, is spread over all parts of
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              the furnace, so that the charcoal in it may be kindled; any charcoal which
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              remains in the receiving-pit is thrown into the passage, so that it may likewise
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              be heated. </s>
              <s>If this has not been done, the silver-lead alloy liquated from the
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              cakes is frozen by the coldness of the passage, and does not run down into the
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              receiving-pit.</s>
            </p>
            <p type="main">
              <s>After a quarter of an hour the cakes begin to drip silver-lead alloy,
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              18
                <emph.end type="sup"/>
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              which runs down through the openings between the copper plates into the
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              passage. </s>
              <s>When the long pieces of charcoal have burned up, if the cakes
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              lean toward the wall, they are placed upright again with a hooked bar, but
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              if they lean toward the front bar they are propped up by charcoal; more­
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              over, if some cakes shrink more than the rest, charcoal is added to the former
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              and not to the others. </s>
              <s>The silver drips together with the lead, for both melt
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              more rapidly than copper. </s>
              <s>The liquation thorns do not flow away, but remain
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              in the passage, and should be turned over frequently with a hooked bar, in
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              order that the silver-lead may liquate away from them and flow down into
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              the receiving pit; that which remains is again melted in the blast furnace,
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              while that which flows into the receiving pit is at once carried with the remain­</s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>
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