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

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    <archimedes>
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              <s>
                <pb pagenum="462"/>
              which I had not before obſerved, to wit, that in the Aſcent of the
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              Plate out of the water, it draws after it another Plate
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              (if I may ſo
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              call it)
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              of water, which before it divides and parts from the inferiour
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              Surface of the Plate of Lead, is raiſed above the Levell of the other
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              water, more than the thickneſs of the back of a Knife: Then he
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              goeth to repeat the Experiment with the Ball, and makes me ſee,
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              that it is but a very ſmall quantity of water, which cleaves to its
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              compacted and contracted Figure: and then he ſubjoynes, that its
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              no wonder, if in ſeperating the thinne and broad Plate from the
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              water, we meet with much greater Reſiſtance, than in ſeperating the
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              Ball, ſince together with the Plate, we are to raiſe a great quantity of
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              water, which occurreth not in the Ball: He telleth me moreover,
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              how that our Queſtion is, whether the Reſiſtance of Elevation be
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              greater in a dilated Plate of Lead, than in a Ball, and not whether
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              more reſiſteth a Plate of Lead with a great quantity of water, or a
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              Ball with a very little water: He ſheweth me in the cloſe, that the
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              putting the Plate and the Ball firſt into the water, to make proofe
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              thereby of their Reſiſtance in the Air, is beſides our caſe, which
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              treats of Elivating in the Air, and of things placed in the Air, and
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              not of the Reſiſtance that is made in the Confines of the Air and
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              water, and by things which are part in Air and part in water: and
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              laſtly, they make me feel with my hand, that when the thinne Plate
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              is in the Air, and free from the weight of the water, it is raiſed with
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              the very ſame Force that raiſeth the Ball. </s>
              <s>Seeing, and
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              ing theſe things, I know not what to do, unleſs to grant my ſelf
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              vinced, and to thank ſuch a Friend, for having made me to ſee that
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              which I never till then obſerved: and, being advertiſed by this ſame
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              Accident, to tell my Adverſaries, that our Queſtion is, whether a
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              Board and a Ball of Ebony, equally go to the bottom in water, and
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              not a Ball of Ebony and a Board of Ebony, joyned with another
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              flat Body of Air: and, farthermore, that we ſpeak of ſinking, and
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              not ſinking to the bottom, in water, and not of that which happeneth
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              in the Confines of the water and Air to Bodies that be part in the
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              Air, and part in the water; nor much leſs do we treat of the greater
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              or leſſer Force requiſite in ſeperating this or that Body from the Air;
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              not omitting to tell them, in the laſt place, that the Air doth reſiſt,
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              and gravitate downwards in the water, juſt ſo much as the water (if
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              I may ſo ſpeak) gravitates and reſiſts upwards in the Air, and that the
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              ſame force is required to ſinke a Bladder under water, that is full of
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              Air, as to raiſe it in the Air, being full of water, removing the
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              ſideration of the weight of that Filme or Skinne, and confidering the
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              water and the Air only. </s>
              <s>And it is likewiſe true, that the ſame Force
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              is required to ſink a Cup or ſuch like Veſſell under water, whilſt it is
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              full of Air, as to raiſe it above the Superficies of the water, keeping </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>
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