Agricola, Georgius, De re metallica, 1912/1950

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    <archimedes>
      <text>
        <body>
          <chap>
            <pb pagenum="196"/>
            <p type="main">
              <s>The fifth pump of this kind is partly like the third and partly like the
                <lb/>
              fourth, because it is turned by strong men like the last, and like the third
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              it has two axles and three drums, though each axle is horizontal. </s>
              <s>The
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              journals of each axle are so fitted in the pillows of the beams that they cannot
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              fly out; the lower axle has a crank at one end and a toothed drum at the
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              other end; the upper axle has at one end a drum made of rundles, and at
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              the other end, a drum to which are fixed iron clamps, in which the links of a
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              chain catch in the same way as before, and from the same depth, draw water
                <lb/>
              through pipes by means of balls. </s>
              <s>This revolving machine is turned by two
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              pairs of men alternately, for one pair stands working while the other sits
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              taking a rest; while they are engaged upon the task of turning, one pulls
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              the crank and the other pushes, and the drums help to make the pump turn
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              more easily.</s>
            </p>
            <p type="main">
              <s>The sixth pump of this kind likewise has two axles. </s>
              <s>At one end of the
                <lb/>
              lower axle is a wheel which is turned by two men treading, this is twenty­
                <lb/>
              three feet high and four feet wide, so that one man may stand alongside
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              the other. </s>
              <s>At the other end of this axle is a toothed wheel. </s>
              <s>The upper
                <emph type="sup"/>
              19
                <emph.end type="sup"/>
                <lb/>
              axle has two drums and one wheel; the first drum is made of rundles, and to
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              the other there are fixed the iron clamps. </s>
              <s>The wheel is like the one on the
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              second machine which is chiefly used for drawing earth and broken rock
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              out of shafts. </s>
              <s>The treaders, to prevent themselves from falling, grasp in
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              their hands poles which are fixed to the inner sides of the wheel. </s>
              <s>When
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              they turn this wheel, the toothed drum being made to revolve, sets in motion
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              the other drum which is made of rundles, by which means again the links
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              of the chain catch to the cleats of the third drum and draw water through
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              pipes by means of balls,—from a depth of sixty-six feet.</s>
            </p>
            <p type="main">
              <s>But the largest machine of all those which draw water is the one which
                <lb/>
              follows. </s>
              <s>First of all a reservoir is made in a timbered chamber; this reser­
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              voir is eighteen feet long and twelve feet wide and high. </s>
              <s>Into this reservoir
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              a stream is diverted through a water-race or through the tunnel; it has two
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              entrances and the same number of gates. </s>
              <s>Levers are fixed to the upper part
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              of these gates, by which they can be raised and let down again, so that by one
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              way the gates are opened and in the other way closed. </s>
              <s>Beneath the openings
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              are two plank troughs which carry the water flowing from the reservoir, and
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              pour it on to the buckets of the water-wheel, the impact of which turns the
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              wheel. </s>
              <s>The shorter trough carries the water, which strikes the buckets
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              that turn the wheel toward the reservoir, and the longer trough carries
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              the water which strikes those buckets that turn the wheel in the opposite
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              direction. </s>
              <s>The casing or covering of the wheel is made of joined boards to
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              which strips are affixed on the inner side. </s>
              <s>The wheel itself is thirty-six feet
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              in diameter, and is mortised to an axle, and it has, as I have already said,
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              two rows of buckets, of which one is set the opposite way to the other, so
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              that the wheel may be turned toward the reservoir or in the opposite </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>
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