Galilei, Galileo, The systems of the world, 1661

Page concordance

< >
Scan Original
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
< >
page |< < of 948 > >|
    <archimedes>
      <text>
        <body>
          <chap>
            <p type="main">
              <s>
                <pb xlink:href="065/01/073.jpg" pagenum="67"/>
              go accompanied with thoſe illuminating beams of the Sun.</s>
            </p>
            <p type="main">
              <s>SIMPL. </s>
              <s>This is true, without any contradiction.</s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>But when the Moon is oppoſite to the Sun, what
                <lb/>
              ference is there between the tract of the rayes of your ſight, and
                <lb/>
              that motion which the Suns rayes make?</s>
            </p>
            <p type="main">
              <s>SIMPL. </s>
              <s>Now I underſtand you; for you would ſay, that the
                <lb/>
              rayes of the ſight and thoſe of the Sun, moving by the ſame lines,
                <lb/>
              we cannot perceive any of the obſcure valleys of the Moon. </s>
              <s>Be
                <lb/>
              pleaſed to change this your opinion, that I have either ſimulation
                <lb/>
              or diſſimulation in me; for I proteſt unto you, as I am a
                <lb/>
              man, that I did not gueſſe at this ſolution, nor ſhould I have
                <lb/>
              thought upon it, without your help, or without long ſtudy.</s>
            </p>
            <p type="main">
              <s>SAGR. </s>
              <s>The reſolutions, which between you two have been
                <lb/>
              alledged touching this laſt doubt, hath, to ſpeak the truth,
                <lb/>
              ed me alſo. </s>
              <s>But at the ſame time this conſideration of the
                <lb/>
              fible rayes accompanying the rayes of the Sun, hath begotten in me
                <lb/>
              another ſcruple, about the other part, but I know not whether I
                <lb/>
              can expreſſe it right, or no: for it but juſt now comming into my
                <lb/>
              mind, I have not yet methodized it to my mind: but let us ſee if
                <lb/>
              we can, all together, make it intelligible. </s>
              <s>There is no queſtion,
                <lb/>
              but that the parts towards the circumference of that poliſh't, but not
                <lb/>
              burniſh't Hemiſphere, which is illuminated by the Sun, receiving the
                <lb/>
              rayes obliquely, receive much fewer thereof, than the
                <lb/>
              moſt parts, which receive them directly. </s>
              <s>And its poſſible, that a
                <lb/>
              tract or ſpace of
                <emph type="italics"/>
              v. </s>
              <s>g.
                <emph.end type="italics"/>
              twenty degrees in breadth, and which is
                <lb/>
              wards the extremity of the Hemiſphere, may not receive more rays
                <lb/>
              than another towards the middle parts, of but four degree broad:
                <lb/>
              ſo that that doubtleſs will be much more obſcure than this; and
                <lb/>
              ſuch it will appear to whoever ſhall behold them both in the face,
                <lb/>
              or (as I may ſay) in their full magnitude. </s>
              <s>But if the eye of the
                <lb/>
              beholder were conſtituted in ſuch a place, that the breadth of the
                <lb/>
              twenty degrees of the obſcure ſpace, appeared not to it longer
                <lb/>
              than one of four degrees, placed in the midſt of the Hemiſphere,
                <lb/>
              I hold it not impoſſible for it to appear to the ſaid beholder
                <lb/>
              qually clear and lucid with the other; becauſe, finally, between
                <lb/>
              two equal angles, to wit, of four degrees apiece, there come to
                <lb/>
              the eye the reflections of two equal numbers of rayes: namely,
                <lb/>
              thoſe which are reflected from the middlemoſt ſpace, four degrees
                <lb/>
              in breadth, and thoſe reflected from the other of twenty degrees,
                <lb/>
              but ſeen by compreſſion, under the quantity of four degrees: and
                <lb/>
              ſuch a ſituation ſhall the eye obtain, when it is placed between the
                <lb/>
              ſaid Hemiſphere, and the body which illuminates it; for then the
                <lb/>
              ſight and rayes move in the ſame lines. </s>
              <s>It ſeemeth not impoſſible
                <lb/>
              therefore, but that the Moon may be of a very equal ſuperficies;
                <lb/>
              and that nevertheleſſe, it may appear when it is at the full, no leſs </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>
Impressum