Salusbury, Thomas, Mathematical collections and translations (Tome I), 1667
page |< < of 701 > >|
    <archimedes>
      <text>
        <body>
          <chap>
            <p type="main">
              <s>
                <pb xlink:href="040/01/439.jpg" pagenum="417"/>
              it hath not been likewiſe with a perfect curioſity inquired, what
                <lb/>
              its courſe is thorow the particular arches of the Zodiack. </s>
              <s>That
                <lb/>
              therefore the Earth and Moon in running through the Zodiack,
                <lb/>
              that is round the Grand Orb, do ſomewhat accellerate at the
                <lb/>
              Moons change, and retard at its full, ought not to be doubted;
                <lb/>
              for that the ſaid difference is not manifeſt, which cometh to be
                <lb/>
              unobſerved upon two accounts; Firſt, Becauſe it hath not been
                <lb/>
              lookt for. </s>
              <s>Secondly, Becauſe that its poſſible it may not be very
                <lb/>
              great. </s>
              <s>Nor is there any need that it ſhould be great, for the
                <lb/>
              ducing the effect that we ſee in the alteration of the greatneſs of
                <lb/>
              ebbings and flowings. </s>
              <s>For not onely thoſe alterations, but the
                <lb/>
                <arrow.to.target n="marg812"/>
                <lb/>
              Tides themſelves are but ſmall matters in reſpect of the grandure
                <lb/>
              of the ſubjects on which they work; albeit that to us, and to our
                <lb/>
              littleneſs they ſeem great. </s>
              <s>For the addition or ſubduction of
                <lb/>
              one degree of velocity where there are naturally 700, or 1000,
                <lb/>
              can be called no great alteration, either in that which conferreth
                <lb/>
              it, or in that Which receiveth it: the Water of our Mediterrane
                <lb/>
              carried about by the diurnal revolution, maketh about 700 miles
                <lb/>
              an hour, (which is the motion common to the Earth and to it, and
                <lb/>
              therefore not perceptible to us) & that which we ſenſibly diſcern
                <lb/>
              to be made in the ſtreams or currents, is not at the rate of full one
                <lb/>
              mile an hour, (I ſpeak of the main Seas, and not of the Straights)
                <lb/>
              and this is that which altereth the firſt, naturall, and grand
                <lb/>
              tion; and this motion is very great in reſpect of us, and of Ships:
                <lb/>
              for a Veſſel that in a ſtanding Water by the help of Oares can
                <lb/>
              make
                <emph type="italics"/>
              v. </s>
              <s>g.
                <emph.end type="italics"/>
              three miles an hour, in that ſame current will row
                <lb/>
              twice as far with the ſtream as againſt it: A notable difference
                <lb/>
              in the motion of the Boat, though but very ſmall in the motion
                <lb/>
              of the Sea, which is altered but its ſeven hundredth part. </s>
              <s>The
                <lb/>
              like I ſay of its riſing, and falling one, two, or three feet; and
                <lb/>
              ſcarcely four or five in the utmoſt bounds of a ſtreight, two
                <lb/>
              ſand, or more miles long, and where there are depths of hundreds
                <lb/>
              of feet; this alteration is much leſs than if in one of the Boats
                <lb/>
              that bring us freſh Water, the ſaid Water upon the arreſt of the
                <lb/>
              Boat ſhould riſe at the Prow the thickneſs of a leaf. </s>
              <s>I conclude
                <lb/>
              therefore that very ſmall alterations in reſpect of the immenſe
                <lb/>
              greatneſs, and extraordinary velocity of the Seas, is ſufficient to
                <lb/>
              make therein great mutations in relation to our ſmallneſs, and to
                <lb/>
              our accidents.</s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg807"/>
                <emph type="italics"/>
              Many things
                <lb/>
              may remain as yet
                <lb/>
              unobſerved in
                <lb/>
              ſtronomy.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg808"/>
              Saturn
                <emph type="italics"/>
              for its
                <lb/>
              ſlowneſs, and
                <emph.end type="italics"/>
                <lb/>
              cury
                <emph type="italics"/>
              for its
                <lb/>
              neſs of appearing
                <lb/>
              were amongſt thoſe
                <lb/>
              that were laſt
                <lb/>
              ſerved.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg809"/>
                <emph type="italics"/>
              Particular
                <lb/>
              ctures of the Orbs
                <lb/>
              of the Planets not
                <lb/>
              yet well reſolved.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg810"/>
                <emph type="italics"/>
              The Sun
                <lb/>
              eth one half of the
                <lb/>
              Zodiack nine days
                <lb/>
              ſooner than the
                <lb/>
              other.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg811"/>
                <emph type="italics"/>
              The Moons
                <lb/>
              tion principally
                <lb/>
              ſought in the
                <lb/>
              count of Eclipſes.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg812"/>
                <emph type="italics"/>
              Ebbings and
                <lb/>
              flowings are petty
                <lb/>
              things in
                <lb/>
              ſon of the vaſtneſs
                <lb/>
              of Seas, and of the
                <lb/>
              velocity of the
                <lb/>
              tion of the
                <lb/>
              ſtrial Globe.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="main">
              <s>SAGR. </s>
              <s>I am fully ſatisfied as to this particular; it remains to
                <lb/>
              declare unto us how thoſe additions and ſubſtractions derived
                <lb/>
              from the diurnal
                <emph type="italics"/>
              Vertigo
                <emph.end type="italics"/>
              are made one while greater, and
                <lb/>
              ther while leſſer; from which alterations you hinted that the
                <lb/>
              nual period of the augmentations and diminutions of the
                <lb/>
              bings and flowings did depend.</s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>
Impressum