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

List of thumbnails

< >
21
21
22
22
23
23
24
24
25
25
26
26
27
27
28
28
29
29
30
30
< >
page |< < of 137 > >|
    <archimedes>
      <text>
        <body>
          <chap>
            <pb xlink:href="068/01/030.jpg" pagenum="16"/>
            <p type="head">
              <s>
                <emph type="italics"/>
              COROLLARIE
                <emph.end type="italics"/>
              XIV.
                <lb/>
                <arrow.to.target n="marg965"/>
              </s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg965"/>
              *
                <emph type="italics"/>
              Arteſia.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="main">
              <s>In the Grand Rivers, which fall into the Sea, as here in
                <emph type="italics"/>
              Italy
                <lb/>
              Po, Adige,
                <emph.end type="italics"/>
              ^{*} and
                <emph type="italics"/>
              Arno,
                <emph.end type="italics"/>
              which are armed with Banks againſt their
                <lb/>
              excreſcencies, its obſerved that far from the Sea, they need
                <lb/>
              Banks of a notable height; which height goeth afterwards by
                <lb/>
              degrees diminiſhing, the more it approacheth to the Sea-coaſts:
                <lb/>
              in ſuch ſort, that the P
                <emph type="italics"/>
              o,
                <emph.end type="italics"/>
              diſtant from the Sea about fifty or ſixty
                <lb/>
              miles at
                <emph type="italics"/>
              Ferara,
                <emph.end type="italics"/>
              ſhall have Banks that be above twenty feet
                <lb/>
              higher than the ordinary Water marks; but ten or twelve miles
                <lb/>
              from the Sea, the Banks are not twelve feet higher than the ſaid
                <lb/>
              ordinary Water-marks, though the breadth of the River be the
                <lb/>
              ſame, ſo that the excreſcence of the ſame Innundation happens
                <lb/>
              to be far greater in meaſure remote from the Sea, then near; and
                <lb/>
              yet it ſhould ſeem, that the ſame quantity of Water paſſing by
                <lb/>
              every piace, the River ſhould need to have the ſame altitude of
                <lb/>
              Banks in all places: But we by our Principles and fundamentals
                <lb/>
              may be able to render the reaſon of that effect, and ſay; That
                <lb/>
              that exceſſe of quantity of Water, above the ordinary Water,
                <lb/>
              goeth alwaies acquiring greater velocity; the nearer it approach­
                <lb/>
              eth the Sea, and therefore decreaſeth in meaſure, and conſequenly
                <lb/>
              in height. </s>
              <s>And this perhaps might have been the cauſe in great
                <lb/>
              part, why the
                <emph type="italics"/>
              Tyber
                <emph.end type="italics"/>
              in the Innundation
                <emph type="italics"/>
              Anno
                <emph.end type="italics"/>
              1578. iſſued not
                <lb/>
              forth of its Channel below
                <emph type="italics"/>
              Rome
                <emph.end type="italics"/>
              towards the Sea.</s>
            </p>
            <p type="head">
              <s>
                <emph type="italics"/>
              COROLLARIE
                <emph.end type="italics"/>
              XV.</s>
            </p>
            <p type="main">
              <s>From the ſame Doctrine may be rendred a moſt manifeſt rea­
                <lb/>
              ſon why the falling Waters go leſſening in their deſcent, ſo
                <lb/>
              that the ſame falling Water, meaſured at the beginning of
                <lb/>
              its fall, is greater, and bigger, and afterwards by degrees leſſeneth
                <lb/>
              in meaſure the more it is remote from the beginning of the fall.
                <lb/>
              </s>
              <s>Which dependeth on no other, than on the acquiſition, which
                <lb/>
              it ſucceſſively makes of greater velocity; it being a moſt fami­
                <lb/>
              liar concluſion among Philoſophers, that grave bodies falling,
                <lb/>
              the more they remove from the beginning of their motion, the
                <lb/>
              more they acquire of ſwiftneſſe; and therefore the Water, as a
                <lb/>
              grave body, falling, gradually velocitates, and therefore de­
                <lb/>
              creaſeth in meaſure, and leſſeneth.</s>
            </p>
            <p type="head">
              <s>
                <emph type="italics"/>
              COROLLARIE
                <emph.end type="italics"/>
              XVI.</s>
            </p>
            <p type="main">
              <s>And on the contrary, the ſpirtings of a Fountain of Water,
                <lb/>
              which ſpring on high, work a contrary effect; namely </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>