Bernoulli, Daniel, Hydrodynamica, sive De viribus et motibus fluidorum commentarii
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          <head xml:id="echoid-head266" xml:space="preserve">Exemplum 4.</head>
          <p>
            <s xml:id="echoid-s7812" xml:space="preserve">§ 15. </s>
            <s xml:id="echoid-s7813" xml:space="preserve">Fieri poteſt, ut altitudo ſuperficiei aqueæ ratione loci, pro quo
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            preſſio indaganda eſt, ſit negativa, veluti in ſiphonibus recurvis aquas ex vaſe
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            uno in aliud humilius poſitum ducentibus: </s>
            <s xml:id="echoid-s7814" xml:space="preserve">Tuncque preſſio fit duplici titulo
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            negativa, nempe = - a - b, denotante a altitudinem loci ſupra ſuperficiem
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            aquæ & </s>
            <s xml:id="echoid-s7815" xml:space="preserve">b altitudinem velocitati aquæ in illo loco debitam.</s>
            <s xml:id="echoid-s7816" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s7817" xml:space="preserve">Iſta vero ſufficient, ut puto, ad recte intelligendam fluidorum moto-
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            rum ſtaticam: </s>
            <s xml:id="echoid-s7818" xml:space="preserve">Venio jam ad alia quædam phænomena, quorum ſolutio ab
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            iſtis, quas dedimus modo, regulis pendet.</s>
            <s xml:id="echoid-s7819" xml:space="preserve"/>
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            <s xml:id="echoid-s7820" xml:space="preserve">§. </s>
            <s xml:id="echoid-s7821" xml:space="preserve">16. </s>
            <s xml:id="echoid-s7822" xml:space="preserve">In Sectione tertia §. </s>
            <s xml:id="echoid-s7823" xml:space="preserve">25. </s>
            <s xml:id="echoid-s7824" xml:space="preserve">mentionem feci cohæſionis aquæ per
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            tubos fluentis: </s>
            <s xml:id="echoid-s7825" xml:space="preserve">veras autem iſtius cohæſionis menſuras ubique definire res eſt,
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            quæ ſine iſta præmiſſa hydraulico-ſtatica expediri nequit: </s>
            <s xml:id="echoid-s7826" xml:space="preserve">neque enim altitudi-
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            nes conſideraſſe verticales ſupra orificium effluxus ſufficit, ut vulgo putatur, ſed
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            oportet etiam noſſe velocitates aquis convenientes, hæque cognoſcuntur ex
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            amplitudinibus. </s>
            <s xml:id="echoid-s7827" xml:space="preserve">Ut vero ſtatim appareat lex generalis in definienda vi cohæ-
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            ſionis ſeu conatu, quo fluida ad mutuam ſeparationem ſolicitantur, dico il-
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            lam vim cohæſionis æqualem eſſe vi, qua latera canalis introrſum premuntur,
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            quam definivimus §. </s>
            <s xml:id="echoid-s7828" xml:space="preserve">10. </s>
            <s xml:id="echoid-s7829" xml:space="preserve">Propoſitio hæc alia demonſtratione egere mihi non
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            videtur; </s>
            <s xml:id="echoid-s7830" xml:space="preserve">prouti enim compreſſio aquæ, ſeu vis quâ ejus partes ad ſe invicem
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            comprimuntur, æqualis eſt ſuperincumbenti columnæ aqueæ ſtagnanti, ita
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            viciſſim conatus fluida ſeparandi æqualis cenſendus eſt appenſæ columnæ ver-
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            ticali aqueæ ſtagnanti, quæ cum aquis præterfluentibus in æquilibrio ſit. </s>
            <s xml:id="echoid-s7831" xml:space="preserve">Exem-
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            plorum loco eadem accipiemus, quibus ſupra pro indicandis aquarum preſſio-
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            nibus negativis uſi ſumus.</s>
            <s xml:id="echoid-s7832" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s7833" xml:space="preserve">(I) In Figura ſeptuageſima quinta §. </s>
            <s xml:id="echoid-s7834" xml:space="preserve">12. </s>
            <s xml:id="echoid-s7835" xml:space="preserve">explicata, ſi in tubulo D L N
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            altitudo D ſupra N talis ſit, ut aqua in eo ſtagnans cum aquis in D præterflu-
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            entibus in æquilibrio ſit, tanta debet eſſe vis cohæſionis in D, ne aqua ibi-
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            dem diſcerpatur, quantam habet pondus columnæ aqueæ ſimilis baſis & </s>
            <s xml:id="echoid-s7836" xml:space="preserve">alti-
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            tudinis verticalis D N. </s>
            <s xml:id="echoid-s7837" xml:space="preserve">Inde intelligitur quod dixi §. </s>
            <s xml:id="echoid-s7838" xml:space="preserve">25. </s>
            <s xml:id="echoid-s7839" xml:space="preserve">Sect. </s>
            <s xml:id="echoid-s7840" xml:space="preserve">3. </s>
            <s xml:id="echoid-s7841" xml:space="preserve">poſſe longi-
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            tudinem tubi ita augeri, ut tandem aquæ deſinant eſſe continuæ in tubo, quin
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            poti{us} in column{as} dividantur, idque fieri in tubis cylindricis cum infra </s>
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