Agricola, Georgius, De re metallica, 1912/1950
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              When the masses of lead are to be melted, the workman first places the wood
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              in the hearth so that one end of each billet faces the wall, and the other end
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              the dipping-pot. </s>
              <s>Then, assisted by other workmen, he pushes the mass
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              of lead forward with crowbars on to a low trolley, and draws it to the
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              crane. </s>
              <s>The trolley consists of planks fastened together, is two and one-half
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              feet wide and five feet long, and has two small iron axles, around which at
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              each end revolve small iron wheels, two palms in diameter and as many digits
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              wide. </s>
              <s>The trolley has a tongue, and attached to this is a rope, by which it is
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              drawn to the crane. </s>
              <s>The crane is exactly similar to those in the second part
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              of the works, except that the crane-arm is not so long. </s>
              <s>The tongs in whose
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              jaws
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              6
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              the masses of lead are seized, are two feet a palm and two digits long;
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              both of the jaws, when struck with a hammer, impinge upon the mass and are
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              driven into it. </s>
              <s>The upper part of both handles of the tongs are curved back,
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              the one to the right, the other to the left, and each handle is engaged in one
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              of the lowest links of two short chains, which are three links long. </s>
              <s>The upper
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              links are engaged in a large round ring, in which is fixed the hook of a chain
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              let down from the pulley of the crane-arm. </s>
              <s>When the crank of the crane
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              is turned, the mass is lifted and is carried by the crane-arm to the hearth and
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              placed on the wood. </s>
              <s>The workmen wheel up one mass after another and
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              place them in a similar manner on the wood of the hearth; masses which
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              weigh a total of about a hundred and sixty
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              centumpondía
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              7
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              are usually placed
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              upon the wood and melted at one time. </s>
              <s>Then a workman throws charcoal
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              on the masses, and all are made ready in the evening. </s>
              <s>If he fears that it may
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              rain, he covers it up with a cover, which may be moved here and there; at the
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              back this cover has two legs, so that the rain which it collects may flow down
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              the slope on to the open ground. </s>
              <s>Early in the morning of the following day,
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              he throws live coals on the charcoal with a shovel, and by this method the
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              masses of lead melt, and from time to time charcoal is added. </s>
              <s>The lead, as
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              soon as it begins to run into the dipping-pot, is ladled out with an iron ladle
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              into copper moulds such as the refiners generally use. </s>
              <s>If it does not cool
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              immediately he pours water over it, and then sticks the pointed pick into
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              it and pulls it out. </s>
              <s>The pointed end of the pick is three palms long and
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              the round end is two digits long. </s>
              <s>It is necessary to smear the moulds with a
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              wash of lute, in order that, when they have been turned upside down and
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              struck with the broad round end of the pick, the cakes of lead may fall out
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              easily. </s>
              <s>If the moulds are not washed over with the lute, there is a risk that
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              they may be melted by the lead and let it through. </s>
              <s>Others take hold of a
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              billet of wood with their left hand, and with the heavy lower end of it they
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              pound the mould, and with the right hand they stick the point of the pick
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              into the cake of lead, and thus pull it out. </s>
              <s>Then immediately the workman
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              pours other lead into the empty moulds, and this he does until the work of
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              melting the lead is finished. </s>
              <s>When the lead is melted, something similar to
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              litharge is produced; but it is no wonder that it should be possible to make
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              </s>
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