Gravesande, Willem Jacob 's, An essay on perspective

Table of contents

< >
[201.] Remarks.
Page: 212 (107)
[202.] Uſe of the Machine. Problem I.
Page: 212 (107)
[203.] Demonstration. Concerning the before-mention’d Inclination of the Mirrours.
Page: 214 (109)
[204.] Prob. II.
Page: 215 (110)
[205.] Prop. III.
Page: 218 (113)
[206.] Problem IV.
Page: 219 (114)
[207.] As the Machine’s Height above the Table, leſs the Glaſs’s focal Length, is to
Page: 219 (114)
[208.] The Height of the Machine above the Table; So is The Glaſſes focal Length, to the Diſtance of the Figure from the Glaſs.
Page: 220 (115)
[209.] 37 Remarks concerning the Repreſentation of Per-ſons Faces.
Page: 220 (115)
[210.] A Deſcription of the Second Machine.
Page: 222 (117)
[211.] The Uſe of this Machine.
Page: 224 (119)
[212.] A Demonſtration of the Inclination of the Looking-Glaſs.
Page: 225 (120)
[213.] FINIS.
Page: 225 (120)
< >
page |< < (101) of 237 > >|
    <echo version="1.0RC">
      <text xml:lang="en" type="free">
        <div xml:id="echoid-div360" type="section" level="1" n="195">
          <pb o="101" file="0177" n="206" rhead="on PERSPECTIVE."/>
          <figure number="71">
            <image file="0177-01" xlink:href="http://echo.mpiwg-berlin.mpg.de/zogilib?fn=/permanent/library/xxxxxxxx/figures/0177-01"/>
          </figure>
        </div>
        <div xml:id="echoid-div363" type="section" level="1" n="196">
          <head xml:id="echoid-head212" style="it" xml:space="preserve">The Uſe of the
            <emph style="sc">Camera</emph>
            <emph style="sc">Obscura</emph>
            <lb/>
          in Deſigning.</head>
          <head xml:id="echoid-head213" xml:space="preserve">
            <emph style="sc">Advertisement</emph>
          .</head>
          <p style="it">
            <s xml:id="echoid-s2237" xml:space="preserve">EVery one knows how eaſy it is by one Convex Glaſs
              <lb/>
            only, to repreſent outward Objects in any darken’d
              <lb/>
            Place, according to their natural Appearances, where
              <lb/>
            the Livelineſs of Colours, and the Diverſity of Mo-
              <lb/>
            tions, are wonderfully pleaſant to behold; </s>
            <s xml:id="echoid-s2238" xml:space="preserve">and it is
              <lb/>
            ſo eaſy to make this Invention uſeful in Deſigning,
              <lb/>
            that our treating of it ſo fully as we have done, is
              <lb/>
            undoubtedly ſomething neceſſary.</s>
            <s xml:id="echoid-s2239" xml:space="preserve"/>
          </p>
          <p style="it">
            <s xml:id="echoid-s2240" xml:space="preserve">A few Hints and Obſervations ſeem to be ſufficient
              <lb/>
            for putting a diligent Perſon in the way of contriving
              <lb/>
            himſelf ſome Machine to perform the Uſes hereafter
              <lb/>
            mentioned; </s>
            <s xml:id="echoid-s2241" xml:space="preserve">whence we might have let him bad the
              <lb/>
            Pleaſure of the Invention himſelf, after it was made
              <lb/>
            eaſy to him. </s>
            <s xml:id="echoid-s2242" xml:space="preserve">And this indeed is what I firſt reſolv’d
              <lb/>
            upon; </s>
            <s xml:id="echoid-s2243" xml:space="preserve">but afterwards conſidering that in the Con-
              <lb/>
            ſtruction of a Machine for facilitating the Buſineſs of
              <lb/>
            Deſigning, ſeveral Things cannot be foreknown till
              <lb/>
            try’d; </s>
            <s xml:id="echoid-s2244" xml:space="preserve">and that much Time may be ſpent in vain, and
              <lb/>
            ſeveral Methods attempted, before one of theſe Ma-
              <lb/>
            chines can be made ſimple and uſeful, as I have found
              <lb/>
            by Experierce: </s>
            <s xml:id="echoid-s2245" xml:space="preserve">Therefore, that others may not be at
              <lb/>
            this Trouble, I ſhall here lay down the Deſcription of
              <lb/>
            two Machines (hoping it will not be unacceptable)
              <lb/>
            which after ſeveral Alterations, in my Opinion, are
              <lb/>
            now made convenient enough.</s>
            <s xml:id="echoid-s2246" xml:space="preserve"/>
          </p>
        </div>
      </text>
    </echo>
Impressum