Agricola, Georgius, De re metallica, 1912/1950

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    <archimedes>
      <text>
        <body>
          <chap>
            <p type="caption">
              <s>
                <pb pagenum="139"/>
              the major spaces on the rod, and those which proceed further, mark the
                <lb/>
              middle of the intervening space which lies between the others. </s>
              <s>The
                <lb/>
              straight lines, which run from the fifth to the sixth semi-circular line, show
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              nothing further. </s>
              <s>Nor does the line which measures the half, show anything
                <lb/>
              when it has already passed from the sixth straight line to the base of the
                <lb/>
              hemicycle. </s>
              <s>When the hemicycle is applied to the cord, if its tongue indicates
                <lb/>
              the sixth straight line which lies between the second and third semi-circular
                <lb/>
              lines, the surveyor counts on the rod six lines which separate the minor
                <lb/>
              spaces, and if the length of this portion of the rod be taken from the second
                <lb/>
              cord, as many times as the cord itself is half-fathoms long, the remaining
                <lb/>
              length of cord shows the distance the tunnel must be driven to reach under
                <lb/>
              the shaft. </s>
              <s>But if he sees that the tongue has gone so far that it marks the
                <lb/>
              sixth line between the fourth and fifth semi-circular lines, he counts six lines
                <lb/>
              which separate the major spaces on the rod; and this entire space is deducted
                <lb/>
              from the length of the second cord, as many times as the number of whole
                <lb/>
              fathoms which the cord contains; and then, in like manner, the remaining
                <lb/>
              length of cord shows us the distance the tunnel must be driven to reach
                <lb/>
              under the shaft.
                <emph type="sup"/>
              19
                <emph.end type="sup"/>
              </s>
            </p>
            <figure number="68"/>
            <p type="caption">
              <s>STRETCHED CORDS: A—FIRST CORD. B—SECOND CORD. C—THIRD CORD.
                <lb/>
              D—TRIANGLE.</s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>
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