Galilei, Galileo, Discourse concerning the natation of bodies, 1663

Page concordance

< >
Scan Original
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
< >
page |< < of 77 > >|
    <archimedes>
      <text>
        <body>
          <chap>
            <pb pagenum="412"/>
            <p type="head">
              <s>THEOREME III.</s>
            </p>
            <p type="main">
              <s>
                <emph type="italics"/>
              A Priſme or regular Cylinder, of a ſubſtance ſpecifically
                <lb/>
              leſs grave than Water, if it ſhould be totally ſubmerged
                <lb/>
              in Water, ſtayes not underneath, but riſeth, though the
                <lb/>
              Water circumfuſed be very little, and in abſolute
                <lb/>
              Gravity, never ſo much inferiour to the Gravity of the
                <lb/>
              ſaid Priſme.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="main">
              <s>Let then the Priſme A E F B, be put into the Veſſell C D F B, the
                <lb/>
              ſame being leſs grave
                <emph type="italics"/>
              in ſpecie
                <emph.end type="italics"/>
              than the Water: and let the
                <lb/>
              Water infuſed riſe to the height of the Priſme: I ſay, that the
                <lb/>
              Priſme left at liberty, it ſhall riſe, being born up
                <lb/>
              by the Water circumfuſed C D E A. </s>
              <s>For the
                <lb/>
                <figure id="fig264" number="3"/>
                <lb/>
              Water C E being ſpecifically more grave than
                <lb/>
              the Solid A F, the abſolute weight of the water
                <lb/>
              C E, ſhall have greater proportion to the
                <lb/>
              lute weight of the Priſme A F, than the Maſs
                <lb/>
              C E hath to the Maſs A F (in regard the Maſs
                <lb/>
              hath the ſame proportion to the Maſs, that the
                <lb/>
              weight abſolute hath to the weight abſolute,
                <lb/>
              in caſe the Maſſes are of the ſame Gravity
                <emph type="italics"/>
              in ſpecie.
                <emph.end type="italics"/>
              ) But
                <lb/>
              the Maſs C E is to the Maſs A F, as the Surface of the water A C, is
                <lb/>
              to the Superficies, or Baſe of the Priſme A B; which is the ſame
                <lb/>
              portion as the aſcent of the Priſme when it riſeth, hath to the deſcent
                <lb/>
              of the water circumfuſed C E.</s>
            </p>
            <p type="main">
              <s>Therefore, the abſolute Gravity of the water C E, hath greater
                <lb/>
              proportion to the abſolute Gravity of the Priſme A F; than the
                <lb/>
              Aſcent of the Priſme A F, hath to the deſcent of the ſaid
                <lb/>
              water C E. </s>
              <s>The Moment, therefore, compounded of the abſolute
                <lb/>
              Gravity of the water C E, and of the Velocity of its deſcent, whilſt
                <lb/>
              it forceably repulſeth and raiſeth the Solid A F, is greater than the
                <lb/>
              Moment compounded of the abſolute Gravity of the Priſme A F, and
                <lb/>
              of the Tardity of its aſcent, with which Moment it contraſts and
                <lb/>
              fiſts the repulſe and violence done it by the Moment of the water:
                <lb/>
              Therefore, the Priſme ſhall be
                <lb/>
                <arrow.to.target n="marg1414"/>
              </s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg1414"/>
              The Proportion
                <lb/>
              according to
                <lb/>
              which the
                <lb/>
              merſion & Na
                <lb/>
              tation of Solids
                <lb/>
              is made.</s>
            </p>
            <p type="main">
              <s>It followes, now, that we proceed forward to demonſtrate more
                <lb/>
              particularly, how much ſuch Solids ſhall be inferiour in Gravity to
                <lb/>
              the water elevated; namely, what part of them ſhall reſt ſubmerged,
                <lb/>
              and what ſhall be viſible above the Surface of the water: but firſt
                <lb/>
              it is neceſſary to demonſtrate the ſubſequent Lemma.</s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>