Agricola, Georgius, De re metallica, 1912/1950

List of thumbnails

< >
351
351 		352
352
353
353 		354
354
355
355 		356
356
357
357 		358
358
359
359 		360
360
< >
page |< < of 679 > >|
    <archimedes>
      <text>
        <body>
          <chap>
            <pb pagenum="327"/>
            <figure number="184"/>
            <p type="caption">
              <s>A—HEAD OF THE SLUICE. B—SIDE-BOARDS. C—LOWER END OF THE SLUICE.
                <lb/>
              D—POCKETS. E—GROOVES. F—STOOLS. G—SHOVEL. H—TUB SET BELOW.
                <lb/>
              I—LAUNDER.</s>
            </p>
            <p type="main">
              <s>Some people cut a number of cross-grooves, one palm distant from each
                <lb/>
              other, in a sluice similarly composed of three planks eight feet long. </s>
              <s>The
                <lb/>
              upper edge of these grooves is sloping, that the particles of gold may slip into
                <lb/>
              them when the washer stirs the sand with a wooden shovel; but their lower
                <lb/>
              edge is vertical so that the gold particles may thus be unable to slide
                <lb/>
              out of them. </s>
              <s>As soon as these grooves are full of gold particles mixed
                <lb/>
              with fine sand, the sluice is removed from the stools and raised up on its
                <lb/>
              head. </s>
              <s>The head in this case is nothing but the upper end of the planks
                <lb/>
              of which the sluice is composed. </s>
              <s>In this way the metallic particles, being
                <lb/>
              turned over backward, fall into another tub, for the small stones and gravel
                <lb/>
              have rolled down the sluice. </s>
              <s>Some people place large bowls under the
                <lb/>
              sluice instead of tubs, and as in the other cases, the unclean concentrates are
                <lb/>
              washed in the small bowl.</s>
            </p>
            <p type="main">
              <s>The Thuringians cut rounded pockets, a digit in diameter and depth, in
                <lb/>
              the head of the sluice, and at the same time they cut grooves reaching from
                <lb/>
              one to another. </s>
              <s>The sluice itself they cover with canvas. </s>
              <s>The sand which </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>
Impressum