Salusbury, Thomas, Mathematical collections and translations (Tome I), 1667

List of thumbnails

< >
361
361 		362
362
363
363 		364
364
365
365 		366
366
367
367 		368
368
369
369 		370
370
< >
page |< < of 701 > >|
    <archimedes>
      <text>
        <body>
          <chap>
            <p type="main">
              <s>
                <pb xlink:href="040/01/371.jpg" pagenum="351"/>
              twice as great as that from the Sun to us) in the ſtar of
                <emph type="italics"/>
              Saturn
                <emph.end type="italics"/>
              is
                <lb/>
              almoſt totally imperceptible, and in
                <emph type="italics"/>
              Jupiter
                <emph.end type="italics"/>
              not very
                <lb/>
              ble, what ſhall we think of the fixed ſtars, which I believe you
                <lb/>
              will not ſcruple to place twice as far off as
                <emph type="italics"/>
              Saturn
                <emph.end type="italics"/>
              ? </s>
              <s>In
                <emph type="italics"/>
              Mars,
                <emph.end type="italics"/>
                <lb/>
              which for that it is nearer to us -------</s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg667"/>
                <emph type="italics"/>
              In objects far
                <lb/>
              remote, and
                <lb/>
              nous, a ſmall
                <lb/>
              proach or receſſion
                <lb/>
              is imperceptible.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="main">
              <s>SIMP. </s>
              <s>Pray Sir, put your ſelf to no farther trouble in this
                <lb/>
              particular, for I already conceive that what hath been ſpoken
                <lb/>
              touching the unaltered apparent magnitude of the fixed ſtars may
                <lb/>
              very well come to paſſe, but what ſhall we ſay of the other
                <lb/>
              ficulty that proceeds from not perceiving any variation in the
                <lb/>
              mutation of aſpect?</s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>We will ſay that which peradventure may ſatisfie
                <lb/>
              you alſo in this particular. </s>
              <s>And to make ſhort, would you not
                <lb/>
              be ſatisfied if there ſhould be diſcovered in the ſtars face
                <lb/>
              tions that you think ought to be diſcovered, in caſe the annual
                <lb/>
              motion belonged to the Earth?</s>
            </p>
            <p type="main">
              <s>SIMP. </s>
              <s>I ſhould ſo doubtleſſe, as to what concerns this
                <lb/>
              ticular.</s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>I could wiſh you would ſay that in caſe ſuch a
                <lb/>
                <arrow.to.target n="marg668"/>
                <lb/>
              rence were diſcovered, nothing more would remain behind, that
                <lb/>
              might render the mobility of the Earth queſtionable. </s>
              <s>But
                <lb/>
              though yet that ſhould not ſenſibly appear, yet is not its
                <lb/>
              bility removed, nor its immobility neceſſarily proved, it being
                <lb/>
              poſſible, (as
                <emph type="italics"/>
              Copernicus
                <emph.end type="italics"/>
              affirmeth) that the immenſe diſtance of
                <lb/>
              the Starry Sphere rendereth ſuch very ſmall
                <emph type="italics"/>
              Phænomena
                <emph.end type="italics"/>
                <lb/>
              vable; the which as already hath been ſaid, may poſſibly not
                <lb/>
              have been hitherto ſo much as ſought for, or if ſought for, yet
                <lb/>
              not ſought for in ſuch a way as they ought, to wit, with that
                <lb/>
                <arrow.to.target n="marg669"/>
                <lb/>
              exactneſſe which to ſo minute a punctuality would be neceſſary;
                <lb/>
              which exactneſſe is very difficult to obtain, as well by reaſon of the
                <lb/>
              deficiency of Aſttonomical Inſtruments, ſubject to many
                <lb/>
              tions, as alſo through the fault of thoſe that manage them with leſs
                <lb/>
              diligence then is requiſite. </s>
              <s>A neceſſary argument how little
                <lb/>
              dit is to be given to thoſe obſervations may be deduced from the
                <lb/>
              differences which we find amongſt Aſtronomers in aſſigning the
                <lb/>
              places, I will not ſay, of the new Stars or Comets, but of the fixed
                <lb/>
              ſtars themſelves, even to the altitudes of the very Poles, in
                <lb/>
              which, moſt an end, they are found to differ from one another
                <lb/>
              many minutes. </s>
              <s>And to ſpeak the truth, who can in a Quadrant,
                <lb/>
              or Sextant, that at moſt ſhall have its ſide ^{*} 3. or 4. yards long,
                <lb/>
                <arrow.to.target n="marg670"/>
                <lb/>
              aſcertain himſelf in the incidence of the perpendicular, or in the
                <lb/>
              direction of the ſights, not to erre two or three minutes, which
                <lb/>
              in its circumference ſhall not amount to the breadth of a grain of
                <lb/>
              ^{*}
                <emph type="italics"/>
              Mylet
                <emph.end type="italics"/>
              ? </s>
              <s>Beſides that, it is almoſt impoſſible, that the Inſtrument
                <lb/>
                <arrow.to.target n="marg671"/>
                <lb/>
              ſhould be made, and kept with abſolute exactneſſe.
                <emph type="italics"/>
              Ptolomey
                <emph.end type="italics"/>
              </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>
Impressum