Newton, Isaac, Philosophia naturalis principia mathematica, 1713

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    <archimedes>
      <text>
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          <chap>
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              <s>
                <pb xlink:href="039/01/013.jpg"/>
              totius moles in binas quaſcunque partes, vel æquales vel utcunque
                <lb/>
              inæquales: jam ſi pondera partium non eſſent in ſe mutuo æqua­
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              lia; cederet pondus minus majori, & partes conjunctæ pergerent
                <lb/>
              recta moveri ad infinitum, verſus plagam in quam tendit pondus
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              majus: omnino contra Experientiam. </s>
              <s>ItaQ.E.D.cendum erit, pon­
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              dera partium in æquilibrio eſſe conſtituta: hoc eſt, Gravitatis
                <lb/>
              actionem eſſe mutuam & utrinque æqualem. </s>
            </p>
            <p type="main">
              <s>Pondera corporum, æqualiter a centro Terræ diſtantium, ſunt ut
                <lb/>
              quantitates materiæ in corporibus. </s>
              <s>Hoc utique colligitur ex
                <lb/>
              æquali acceleratione corporum omnium, e quiete per ponderum
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              vires cadentium: nam vires quibus inæqualia corpora æqualiter
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              accelerantur, debent eſſe proportionales quantitatibus materiæ
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              movendæ. </s>
              <s>Jam vero corpora univerſa cadentia æqualiter acce­
                <lb/>
              lerari, ex eo patet, quod in Vacuo
                <emph type="italics"/>
              Boyliano
                <emph.end type="italics"/>
              temporibus æqualibus
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              æqualia ſpatia cadendo deſcribunt, ſublata ſcilicet Aeris reſiſtentia:
                <lb/>
              accuratius autem comprobatur per Experimenta Pendulorum. </s>
            </p>
            <p type="main">
              <s>Vires attractivæ corporum, in æqualibus diſtantiis, ſunt ut
                <lb/>
              quantitates materiæ in corporibus. </s>
              <s>Nam cum corpora in Ter­
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              ram & Terra viciſſim in corpora momentis æqualibus gravitent;
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              Terræ pondus in unumquodque corpus, ſeu vis qua corpus Ter­
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              ram attrahit, æquabitur ponderi corporis ejuſdem in Terram. </s>
              <s>
                <lb/>
              Hoc autem pondus erat ut quantitas materiæ in corpore: itaque
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              vis qua corpus unumquodque Terram attrahit, ſive corporis vis
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              abſoluta, erit ut eadem quantitas materiæ. </s>
            </p>
            <p type="main">
              <s>Oritur ergo & componitur vis attractiva corporum integrorum
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              ex viribus attractivis partium: ſiquidem aucta vel diminuta mole
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              materiæ, oſtenſum eſt, proportionaliter augeri vel diminui ejus vir­
                <lb/>
              tutem. </s>
              <s>Actio itaque Telluris ex conjunctis partium Actionibus
                <lb/>
              conflari cenſenda erit; atque adeo corpora omnia Terreſtria ſe
                <lb/>
              mutuo trahere oportet viribus abſolutis, quæ ſint in ratione ma­
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              teriæ trahentis. </s>
              <s>Hæc eſt natura Gravitatis apud Terram: videa­
                <lb/>
              mus jam qualis ſit in Cælis. </s>
            </p>
            <p type="main">
              <s>Corpus omne perſeverare in ſtatu ſuo vel quieſcendi vel movendi
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              uniformiter in directum, niſi quatenus a viribus impreſſis cogitur
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              ſtatum illum mutare; Naturæ lex eſt ab omnibus recepta Philoſo­
                <lb/>
              phis. </s>
              <s>Inde vero ſequitur, corpora quæ in Curvis moventur, atque
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              adeo de lineis rectis Orbitas ſuas tangentibus jugiter abeunt, Vi
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              aliqua perpetuo agente retineri in itinere curvilineo. </s>
              <s>Planetis
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              igitur in Orbibus curvis revolventibus neceſſario aderit Vis aliqua,
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              per cujus actiones repetitas indeſinenter a Tangentibus deflectantur. </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>