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

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              <s>
                <pb xlink:href="040/01/695.jpg" pagenum="3"/>
              ſuſpition of Arrogance ſay, that thither alſo doth the recourſe to
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              the defects of the matter (able to blemiſh the perfecteſt Mathe­
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              matical Demonſtrations) ſuffice to excuſe the diſobedience of
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                <arrow.to.target n="marg990"/>
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              Machines in concrete, to the ſame abſtracted and Ideal: yet not­
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              withſtanding I will ſpeak it, affirming, That abſtracting all imper­
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              fections from the Matter, and ſuppoſing it moſt perfect, and unal­
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              terable, and from all accidental mutation exempt, yet neverthe­
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              leſſe its only being Material, cauſeth, that the greater Machine,
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              made of the ſame matter, and with the ſame proportions, as the
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              leſſer; ſhall anſwer in all other conditions to the leſſer in exact
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              Symetry, except in ſtrength, and reſiſtance againſt violent invaſi­
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              ons: but the greater it is, ſo much in proportion ſhall it be wea­
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              ker. </s>
              <s>And becauſe I ſuppoſe the Matter to be unalterable, that is
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              alwaies the ſame, it is manifeſt, that one may produce Demonſtra­
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              tions of it, no leſſe ſimply and purely Mathematical, then of eter­
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              nal, and neceſſary Affections: Therefore,
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              Sagredus,
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              Revoke the
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              opinion which you, and, it may be, all the reſt hold, that have ſtu­
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              died the Mechanicks; that Machines, and Frames compoſed of the
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              ſame Matter, with punctual obſervation of the ſelf ſame proporti­
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              on between their parts, ought to be equally, or to ſay better, pro­
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              portionally diſpoſed to Reſiſt; and to yield to External injuries
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              and aſſaults: For if it may be Geometrically demonſtrated, that
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              the greater are alwaies in proportion leſs able to reſiſt, than the
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              leſſe; ſo that in fine there is not only in all Machines & Fabricks
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              Artiſicial, but Natural alſo, a term neceſſarily aſcribed, beyond
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              which neither Art, nor Nature may paſſe; may paſſe, I ſay, al­
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              waies obſerving the ſame proportions with the Identity of the
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              Matter.</s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg989"/>
                <emph type="italics"/>
              Many Machines
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              may be made more
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              exact in great than
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              in little.
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              </s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg990"/>
                <emph type="italics"/>
              Great Material
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              Machines, al­
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              though framed In
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              the ſame proportion
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              as others of the
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              ſame Matter that
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              are leſſer, are leſſe
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              ſtrong and able to
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              reſiſt external Im­
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              petuſs's than the
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              leſſer.
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              </s>
            </p>
            <p type="main">
              <s>SAGR. </s>
              <s>I already feel my Brains to turn round, and my Mind,
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              (like a Cloud unwillingly opened by the Lightning,) I perceive
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              to be ſurprized with a tranſcient, and unuſual Light, which from
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              affar off twinkleth, and ſuddenly aſtoniſheth me; and with ab­
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              ſtruce, ſtrange, and indigeſted imaginations. </s>
              <s>And from what hath
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              been ſpoken, it ſeems to follow, that, it is a thing impoſſible to
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              frame two Fabricks of the ſame Matter, alike, and unequal, and
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              between themſelves in proportion equally able to Reſiſt; and
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              were it to be done, yet it would be impoſſible to find two only
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              Launces of the ſame wood, alike between themſelves in ſtrength,
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                <arrow.to.target n="marg991"/>
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              and toughneſſe, but unequal in bigneſſe.</s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg991"/>
                <emph type="italics"/>
              A Wooden Launce
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              fixed in a Wall at
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              Right-Angles, and
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              reduced to ſuch a
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              length and thick­
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              neſſe as that it may
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              endure, but made a
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              hairs breadth big­
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              ger, breaketh with
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              its own weight, is
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              ſingly one and no
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              more.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>So it is Sir; and the better to aſſure you that we con­
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              cur in opinion, I ſay, that if we take a Launce of wood of ſuch a
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              length and thickneſſe, that being fixed faſt
                <emph type="italics"/>
              (v. </s>
              <s>g.)
                <emph.end type="italics"/>
              in a Wall at
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              Right Angles, that is parallel to the Horizon, it is reduced to the
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              utmoſt length, that it will hold at, ſo that lengthened never­
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              ſo-little more, it would break, being over-burthened with its own </s>
            </p>
          </chap>
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