Salusbury, Thomas, Mathematical collections and translations (Tome I), 1667

List of thumbnails

< >
91
91
92
92
93
93
94
94
95
95
96
96
97
97
98
98
99
99
100
100
< >
page |< < of 701 > >|
    <archimedes>
      <text>
        <body>
          <chap>
            <pb xlink:href="040/01/737.jpg" pagenum="45"/>
            <p type="main">
              <s>Now if we apply this, that hath been demonſtrated, to our
                <lb/>
              purpoſe; preſuppoſing that that ſame Cylinder of Silver, that was
                <lb/>
              gilded whilſt it was no more than half a yard long, and four or five
                <lb/>
              Inches thick, being diſgroſſed to the ſineneſs of an hair, is prolon­
                <lb/>
              ged unto the extenſion of twenty thouſand yards (for its length
                <lb/>
              would be much greater) we ſhall find its Superficies augmented
                <lb/>
              to two hundred times its former greatneſs: and conſequently, thoſe
                <lb/>
              Leaves of Gold, which were laid on ten in number, being diſten­
                <lb/>
              ded on a Superficies two hundred times bigger, aſſure us that the
                <lb/>
              Gold which covereth the Superficies of the ſo many yards of Wyer
                <lb/>
              is left of no greater thickneſs than the twentieth part of a Leaf of
                <lb/>
              ordinary Beaten-Gold. </s>
              <s>Conſider, now, how great its thinneſs is, and
                <lb/>
              whether it is poſſible to imagine it done without an immenſe di­
                <lb/>
              ſtention of its parts: and whether this ſeem to you an Experi­
                <lb/>
              ment, that tendeth likewiſe towards a compoſition of infinite In­
                <lb/>
              diviſibles in Phyſical Matters: Howbeit there want not other more
                <lb/>
              ſtrong and neceſſary proofs of the ſame.</s>
            </p>
            <p type="main">
              <s>SAGR. </s>
              <s>The Demonſtration ſeemeth to me ſo ingenuous, that
                <lb/>
              although it ſhould not be of force enough to prove that firſt intent
                <lb/>
              for which it was produced, (and yet, in my opinion, it plainly
                <lb/>
              makes it out) yet nevertheleſs that ſhort ſpace of time was well
                <lb/>
              ſpent which hath been employed in hearing of it.</s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>In regard I ſee, that you are ſo well pleaſed with theſe
                <lb/>
              Geometrical Demonſtrations, which bring with them certain pro.
                <lb/>
              </s>
              <s>fit, I will give you the fellow to this, which ſatisfieth to a very cu­
                <lb/>
              rious Queſtion. </s>
              <s>In the former we have that which hapneth in
                <lb/>
              Cylinders that are equall, but of different heights or lengths: it
                <lb/>
              will be convenient, that you alſo hear that which occurreth in Cy­
                <lb/>
              linders equal in Superficies, but unequal in heights; my meaning
                <lb/>
              alwaies is, in thoſe Superficies only that encompaſs them about,
                <lb/>
              that is, not comprehending the two Baſes ſuperiour and inferiour.
                <lb/>
              </s>
              <s>I ſay, therefore, that</s>
            </p>
            <p type="head">
              <s>PROPOSITION.</s>
            </p>
            <p type="main">
              <s>
                <emph type="italics"/>
              Upon Cylinders, the Superficies of which the Baſes be­
                <lb/>
              ing ſubſtracted are equal, have the ſame proportion
                <lb/>
              to one another as their heights Reciprocally taken.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="main">
              <s>Let the Superficies of the two Cylinders A E and C F be
                <lb/>
              equall; but the height of this C D greater than the height
                <lb/>
              of the other A B. </s>
              <s>I ſay, that the Cylinder A E hath the
                <lb/>
              ſame proportion to the Cylinder C F, that the height C D hath
                <lb/>
              to A B. </s>
              <s>Becauſe therefore the Superficies C F is equall to the </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>