Castelli, Benedetto, Of the mensuration of running waters, 1661

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            <pb xlink:href="068/01/022.jpg" pagenum="8"/>
            <p type="head">
              <s>
                <emph type="italics"/>
              COROLLARIE
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              VII.</s>
            </p>
            <p type="main">
              <s>Likewiſe, from the things demonſtrated may be concluded,
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              that the windes, which ſtop a
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              R
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              iver, and blowing againſt the
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              Current, retard its courſe and ordinary velocity ſhall neceſſarily
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              amplifie the meaſure of the ſame River, and conſequently ſhall
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              be, in great part, cauſes; or we may ſay, potent con-cauſes of
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              making the extraordinary inundations which Rivers uſe to make.
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              </s>
              <s>And its moſt certain, that as often as a ſtrong and continual wind
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              ſhall blow againſt the Current of a River, and ſhall reduce the
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              water of the River to ſuch tardity of motion, that in the time
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              wherein before it run five miles, it now moveth but one, ſuch a
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              River will increaſe to five times the meaſure, though there ſhould
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              not be added any other quantity of water; which thing indeed
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              hath in it ſomething of ſtrange, but it is moſt certain, for that
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              look what proportion the waters velocity before the winde, hath
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              to the velocity after the winde, and ſuch reciprocally is the mea­
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              ſure of the ſame water after the winde, to the meaſure before
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              the winde; and becauſe it hath been ſuppoſed in our caſe that the
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              velocity is diminiſhed to a fifth part, therefore the meaſure ſhall
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              be increaſed five times more than that, which it was before.</s>
            </p>
            <p type="head">
              <s>
                <emph type="italics"/>
              COROLLARIE
                <emph.end type="italics"/>
              VIII.</s>
            </p>
            <p type="main">
              <s>We have alſo probable the cauſe of the inundations of
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              Tyber,
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              which befel at
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              Rome,
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              in the time of
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              Alexander
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              the Sixth, & of
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                <emph type="italics"/>
              Clement
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              the Seventh; which innundations came in a ſerene time,
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              and without great thaws of the Snows; which therefore much
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              puzzled the wits of thoſe times. </s>
              <s>But we may with much pro­
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              bability affirm, That the River roſe to ſuch a height and excreſ­
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              cence, by the retardation of the Waters dependant on the
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              boiſtrous and conſtant Winds, that blew in thoſe times, as is no­
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              red in the memorials.</s>
            </p>
            <p type="head">
              <s>
                <emph type="italics"/>
              COROLLARIE.
                <emph.end type="italics"/>
              IX.</s>
            </p>
            <p type="main">
              <s>It being moſt manifeſt, that by the great abundance of Water
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              the Torrents may increaſe, and of themſelves alone exorbitantly
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              ſwell the River; and having demonſtrated that alſo without new
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              Water, but onely by the notable retardment the River riſeth and
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              increaſeth in meaſure, in proportion as the velocity decreaſeth:
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              hence it is apparent, that each of theſe cauſes being able of it ſelf,
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              and ſeparate from the other to ſwell the River; when it ſhall
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              happen that both theſe two cauſes conſpire the augmentation of </s>
            </p>
          </chap>
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      </text>
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