Agricola, Georgius, De re metallica, 1912/1950

Table of figures

< >
[Figure 111]
Page: 233
[Figure 112]
Page: 235
[Figure 113]
Page: 237
[Figure 114]
Page: 239
[Figure 115]
Page: 240
[Figure 116]
Page: 241
[Figure 117]
Page: 242
[Figure 118]
Page: 243
[Figure 119]
Page: 244
[Figure 120]
Page: 245
[Figure 121]
Page: 246
[Figure 122]
Page: 247
[Figure 123]
Page: 249
[Figure 124]
Page: 250
[Figure 125]
Page: 251
[Figure 126]
Page: 256
[Figure 127]
Page: 261
[Figure 128]
Page: 261
[Figure 129]
Page: 262
[Figure 130]
Page: 265
[Figure 131]
Page: 266
[Figure 132]
Page: 267
[Figure 133]
Page: 269
[Figure 134]
Page: 278
[Figure 135]
Page: 278
[Figure 136]
Page: 279
[Figure 137]
Page: 288
[Figure 138]
Page: 293
[Figure 139]
Page: 300
[Figure 140]
Page: 303
< >
page |< < of 679 > >|
    <archimedes>
      <text>
        <body>
          <chap>
            <p type="main">
              <s>
                <pb pagenum="250"/>
              copper is not wholly liquefied; if he finds this is the case, he again places a
                <lb/>
              large piece of charcoal in the crucible, and replaces the glowing charcoal which
                <lb/>
              had been removed, and again blows the bellows for a short time. </s>
              <s>When all
                <lb/>
              the copper has melted he stops using the bellows, for if he were to continue
                <lb/>
              to use them, the fire would consume part of the copper, and then that which
                <lb/>
              remained would be richer than the cake from which it had been cut; this is
                <lb/>
              no small mistake. </s>
              <s>Therefore, as soon as the copper has become sufficiently
                <lb/>
              liquified, he pours it out into a little iron mould, which may be large or small,
                <lb/>
              according as more or less copper is melted in the crucible for the purpose of the
                <lb/>
              assay. </s>
              <s>The mould has a handle, likewise made of iron, by which it is held
                <lb/>
              when the copper is poured in, after which, he plunges it into a tub of water
                <lb/>
              placed near at hand, that the copper may be cooled. </s>
              <s>Then he again dries the
                <lb/>
              copper by the fire, and cuts off its point with an iron wedge; the portion
                <lb/>
              nearest the point he hammers on an anvil and makes into a leaf, which he
                <lb/>
              cuts into pieces.</s>
            </p>
            <figure number="137"/>
            <p type="caption">
              <s>A—IRON MOULD. B—ITS HANDLE.</s>
            </p>
            <p type="main">
              <s>Others stir the molten copper with a stick of linden tree charcoal, and
                <lb/>
              then pour it over a bundle of new clean birch twigs, beneath which is placed
                <lb/>
              a wooden tub of sufficient size and full of water, and in this manner the copper
                <lb/>
              is broken up into little granules as small as hemp seeds. </s>
              <s>Others employ straw
                <lb/>
              in place of twigs. </s>
              <s>Others place a broad stone in a tub and pour in enough
                <lb/>
              water to cover the stone, then they run out the molten copper from the
                <lb/>
              crucible on to the stone, from which the minute granules roll off; others
                <lb/>
              pour the molten copper into water and stir it until it is resolved into granules.
                <lb/>
              </s>
              <s>The fire does not easily melt the copper in the cupel unless it has been poured
                <lb/>
              and a thin leaf made of it, or unless it has been resolved into granules or
                <lb/>
              made into filings; and if it does not melt, all the labour has been undertaken
                <lb/>
              in vain. </s>
              <s>In order that they may be accurately weighed out, silver and lead
                <lb/>
              are resolved into granules in the same manner as copper. </s>
              <s>But to return
                <lb/>
              to the assay of copper. </s>
              <s>When the copper has been prepared by these
                <lb/>
              methods, if it is free of lead and iron, and rich in silver, to each
                <emph type="italics"/>
              centumpon­
                <lb/>
              díum
                <emph.end type="italics"/>
              (lesser weights) add one and a half
                <emph type="italics"/>
              unciae
                <emph.end type="italics"/>
              of lead (larger weights). If,
                <lb/>
              however, the copper contains some lead, add one
                <emph type="italics"/>
              uncia
                <emph.end type="italics"/>
              of lead; if it contains
                <lb/>
              iron, add two
                <emph type="italics"/>
              unciae.
                <emph.end type="italics"/>
              </s>
              <s> First put the lead into a cupel, and after it begins
                <lb/>
              to smoke, add the copper; the fire generally consumes the copper, together
                <lb/>
              with the lead, in about one hour and a quarter. </s>
              <s>When this is done, the silver </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>
Impressum