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

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              <s>
                <pb pagenum="476"/>
              remember, for the removall of an Error that is too common; That
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              that Ship or other whatſoever Body, that on the depth of an hundred
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              or a thouſand fathom, ſwims with ſubmerging only ſix fathom of its
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              own height, [
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              or in the Sea dialect, that draws ſix fathom water
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              ] ſhall
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              ſwim in the ſame manner in water, that hath but ſix fathom and half
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              an Inch of depth. </s>
              <s>Nor do I on the other ſide, think that it can be
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              ſaid, that the ſuperiour parts of the water are the more denſe,
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              though a moſt grave Authour hath eſteemed the ſuperiour water in
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              the Sea to be ſo, grounding his opinion upon its being more ſalt, than
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              that at the bottom: but I doubt the Experiment, whether hitherto
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              in taking the water from the bottom, the Obſervatour did not light
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              upon ſome ſpring of freſh water there ſpouting up: but we plainly
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              ſee on the contrary, the freſh Waters of Rivers to dilate themſelves
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              for ſome miles beyond their place of meeting with the ſalt water of
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              the Sea, without deſcending in it, or mixing with it, unleſs by the
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              intervention of ſome commotion or turbulency of the Windes.</s>
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            <p type="margin">
              <s>
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              A Ship that
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              in 100 Fathome
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              water draweth
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              6 Fathome, ſhall
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              float in 6
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              thome and 1/2 an
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              Inch of depth.</s>
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              <s>But returning to
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              Aristotle,
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              I ſay, that the breadth of Figure hath
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              nothing to do in this buſineſs more or leſs, becauſe the ſaid Plate of
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              Lead, or other Matter, cut into long Slices, ſwim neither more nor
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              leſs; and the ſame ſhall the Slices do, being cut anew into little
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              pieces, becauſe its not the breadth but the thickneſs that operates in
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              this buſineſs. </s>
              <s>I ſay farther, that in caſe it were really true, that the
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              Renitence to Diviſion were the proper Cauſe of ſwimming, the
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              gures more narrow and ſhort, would much better ſwim than the more
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              ſpacious and broad, ſo that augmenting the breadth of the Figure,
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              the facility of ſupernatation will be deminiſhed, and decreaſing, that
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              this will encreaſe.</s>
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            <p type="margin">
              <s>
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              Thickneſs not
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              breadth of
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              gure to be
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              ſpected in
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              tation.</s>
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              <s>
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              Were
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              tence the cauſe
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              of Natation,
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              breadth of
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              gure would
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              hinder the
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              ſwiming of
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              dies.</s>
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            <p type="main">
              <s>And for declaration of what I ſay, conſider that when a thin Plate
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              of Lead deſcends, dividing the water, the Diviſion and
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              ation is made between the parts of the water, invironing the
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              ter or Circumference of the ſaid Plate, and according to the
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              neſs greater or leſſer of that circuit, it hath to divide a greater or
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              leſſer quantity of water, ſo that if the circuit, ſuppoſe of a Board,
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              be ten Feet in ſinking it flatways, it is to make the ſeperation and
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              diviſion, and to ſo ſpeak, an inciſſion upon ten Feet of water; and
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              likewiſe a leſſer Board that is four Feet in Perimeter, muſt make an
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              inceſſion of four Feet. </s>
              <s>This granted, he that hath any knowledge
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              in Geometry, will comprehend, not only that a Board ſawed in many
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              long thin pieces, will much better float than when it was entire, but
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              that all Figures, the more ſhort and narrow they be, ſhall ſo much the
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              better ſwim. </s>
              <s>Let the Board ABCD be, for Example, eight
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              Palmes long, and five broad, its circuit ſhall be twenty ſix Palmes;
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              and ſo many muſt the inceſſion be, which it ſhall make in the water to
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              deſcend therein: but if we do ſaw ir, as ſuppoſe into eight little </s>
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          </chap>
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