Bernoulli, Daniel, Hydrodynamica, sive De viribus et motibus fluidorum commentarii
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              <pb o="291" file="0305" n="305" rhead="SECTIO DECIMA TERTIA."/>
            videbitur quibusdam accuratus, habeo autem aliam demonſtrationem directam,
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            quæ nova proprietate innititur Mechanica mihi aliquando obſervata, quam-
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            que hic communicabo, tum quia dictam demonſtrationem facillime quivis in-
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            de deducere, tum etiam quia ad alios uſus eandem impendere poterit: </s>
            <s xml:id="echoid-s8661" xml:space="preserve">Ita au-
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            tem ſe habet.</s>
            <s xml:id="echoid-s8662" xml:space="preserve"/>
          </p>
          <p style="it">
            <s xml:id="echoid-s8663" xml:space="preserve">Si cerpus movetur velocitate uniformi, directiones autem ſuas con-
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            t
              <unsure/>
            inue mutat à cauſis quibuſcunque & </s>
            <s xml:id="echoid-s8664" xml:space="preserve">utcunque agentibus, donec directionem
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            acquiſiverit perpendicularem ad primam directionem, ſique ſingulæ preßiones
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            corpus deflectentes reſolvantur in duas claſſes, alteram parallelam primæ dire-
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            ctioni, alteram perpendicularem; </s>
            <s xml:id="echoid-s8665" xml:space="preserve">Denique ſi preßiones ſingulæ parallelæ multi-
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            plicantur per ſuatempora; </s>
            <s xml:id="echoid-s8666" xml:space="preserve">dico fore ſummam productorum conſtanter eandem,
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            & </s>
            <s xml:id="echoid-s8667" xml:space="preserve">quidem æqualem ei, quæ totum motum à quiete generare aut generatum
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            totum abſorbere valet.</s>
            <s xml:id="echoid-s8668" xml:space="preserve"/>
          </p>
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            <s xml:id="echoid-s8669" xml:space="preserve">Hâc affectione Dynamica, cum utimur in præſenti noſtro negotio, con-
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            ſideranda eſt lamina E F, quæ ſua in aquas reactione, earundem directionem
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            mutat, uſque dum perpendicularis ad primam facta fuerit: </s>
            <s xml:id="echoid-s8670" xml:space="preserve">Ergo propoſitio
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            præcedentis paragraphi ope hujus affectionis eodem modo demonſtrabitur,
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            quo uſi ſumus §. </s>
            <s xml:id="echoid-s8671" xml:space="preserve">4. </s>
            <s xml:id="echoid-s8672" xml:space="preserve">ad determinandam vim repellentem ope principii §. </s>
            <s xml:id="echoid-s8673" xml:space="preserve">3. </s>
            <s xml:id="echoid-s8674" xml:space="preserve">ex-
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            poſiti. </s>
            <s xml:id="echoid-s8675" xml:space="preserve">Hæc igitur vera idea videtur, quam de impetu aquarum mente conci-
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            pere debemus: </s>
            <s xml:id="echoid-s8676" xml:space="preserve">ponit autem guttas aquæ ſingulas ſecundum directionem lami-
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            næ ad latera reſilire, à quâ indole aquas non recedere ſemper obſervavi: </s>
            <s xml:id="echoid-s8677" xml:space="preserve">vidi
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            tamen etiam guttulas aliquas ſed paucas retrorſum reſilire; </s>
            <s xml:id="echoid-s8678" xml:space="preserve">hæ autem majorem
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            preſſionem producunt, quam quæ ad latera deflectuntur: </s>
            <s xml:id="echoid-s8679" xml:space="preserve">Et eo ipſo inducor, ut
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            firmiter credam, ſi vena aquea magno impetu oblique contra planum impin-
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            gat, v. </s>
            <s xml:id="echoid-s8680" xml:space="preserve">gr. </s>
            <s xml:id="echoid-s8681" xml:space="preserve">ſub angulo triginta graduum, preſſionem inde orituram pluſquam
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            dimidiam ejus, quæ à vena eadem directe impingente oritur, cum ſecundum
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            regulas ordinarias exactè dimidiam vim exerere deberet: </s>
            <s xml:id="echoid-s8682" xml:space="preserve">ratio ejus rei eſt, quod
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            in impulſu obliquo plures particulæ reſilire poſſint, quam in directo, imo fe-
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            re omnes, ſi magna fuerit velocitas.</s>
            <s xml:id="echoid-s8683" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s8684" xml:space="preserve">Si autem omnes ita reſilire ponantur, ut angulus incidentiæ angulo
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            reflexionis æqualis ſit, tunc uterque impulſus idem cenſendus erit. </s>
            <s xml:id="echoid-s8685" xml:space="preserve">Optimus
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            hic aquarum preſſiones æſtimandi modus eſt, qui ratiocinio à poſteriori inni-
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            titur.</s>
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