Barrow, Isaac, Lectiones opticae & geometricae : in quibus phaenomenon opticorum genuinae rationes investigantur, ac exponuntur: et generalia curvarum linearum symptomata declarantur
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            <s xml:id="echoid-s2842" xml:space="preserve">
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            pillæ latitudinem, ipſum ſpatium KZ non ità magnum eſſe; </s>
            <s xml:id="echoid-s2843" xml:space="preserve">quin inſtat
              <lb/>
            _Puncti_ poſſit cenſeri. </s>
            <s xml:id="echoid-s2844" xml:space="preserve">Quibus expenſis luculentè conſtare videtur pro-
              <lb/>
            poſitum.</s>
            <s xml:id="echoid-s2845" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s2846" xml:space="preserve">XVIII. </s>
            <s xml:id="echoid-s2847" xml:space="preserve">Subdo tantùm, ſi oculus uſquam intra ſpacium ZB ſtatua-
              <lb/>
            tur, viſionem indè confuſam, aut nullam evadere; </s>
            <s xml:id="echoid-s2848" xml:space="preserve">quia nempe tunc
              <lb/>
            reflexi præcipui (ſeu rectiſſimi) oculum convergentes appellent.</s>
            <s xml:id="echoid-s2849" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s2850" xml:space="preserve">XIX. </s>
            <s xml:id="echoid-s2851" xml:space="preserve">Ex his porrò facilè refelluntur, quæ de imaginis loco pleni-
              <lb/>
            que tradunt omnes Optici; </s>
            <s xml:id="echoid-s2852" xml:space="preserve">cum illis noviſſimus _Honor. </s>
            <s xml:id="echoid-s2853" xml:space="preserve">Fabri;_ </s>
            <s xml:id="echoid-s2854" xml:space="preserve">juxta
              <lb/>
            quorum doctrinam imago à puncto reflectionis tanto diſtat intervallo,
              <lb/>
            quanto punctum radians ab eodem ſemovetur; </s>
            <s xml:id="echoid-s2855" xml:space="preserve">ità quidem ut Sol ex hu-
              <lb/>
            juſmodi reflectione conſpicuus ad tantam, quantam directè ſpectatus, di-
              <lb/>
            ſtantiam (eorum inſiſtendo ſententiæ) debeat apparere. </s>
            <s xml:id="echoid-s2856" xml:space="preserve">quod im-
              <lb/>
            mane quantum experientiæ refragatur. </s>
            <s xml:id="echoid-s2857" xml:space="preserve">etenim ſi Soli exponatur _Spt-_
              <lb/>
            _culnm_ RB, (concavum, aut convexum) ſic ut ei Sol quaſi perpen-
              <lb/>
            diculariter immineat, oculúſque prope axem BC conſtituatur uſpi-
              <lb/>
            am; </s>
            <s xml:id="echoid-s2858" xml:space="preserve">ferè circa punctum Z, arbitrante ſenſu, luculenta Solis imago
              <lb/>
            ſeſe præbebit oculo conſpiciendam; </s>
            <s xml:id="echoid-s2859" xml:space="preserve">id quod juxta ratiocinium no-
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            ſtrum neceſſariò debuit evenire. </s>
            <s xml:id="echoid-s2860" xml:space="preserve">verùm hic error (in Opticâ capitalis,
              <lb/>
            & </s>
            <s xml:id="echoid-s2861" xml:space="preserve">quo non ablegato nulla phænomeni cujuſcunque ratio veriſimilis
              <lb/>
            conſtabit) ubique ſe objiciet refutandum. </s>
            <s xml:id="echoid-s2862" xml:space="preserve">hîc itaque pluribus parco;
              <lb/>
            </s>
            <s xml:id="echoid-s2863" xml:space="preserve">pergóque verſus oculum extra radiationis axem poſitum; </s>
            <s xml:id="echoid-s2864" xml:space="preserve">poſtquam
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            unicam hanc præcedentibus adnexam obnſervationem ſubjecero.</s>
            <s xml:id="echoid-s2865" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s2866" xml:space="preserve">XX. </s>
            <s xml:id="echoid-s2867" xml:space="preserve">Majoris Sphæræ portio vehementiùs urit; </s>
            <s xml:id="echoid-s2868" xml:space="preserve">ut & </s>
            <s xml:id="echoid-s2869" xml:space="preserve">Objectum
              <lb/>
            viſibile clariùs atque diſtinctiùs repræſentat, quàm minoris æq@alem
              <lb/>
            obtinens latitudinem portio.</s>
            <s xml:id="echoid-s2870" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s2871" xml:space="preserve">Super eandem nempe ſubtenſam NV inſiſtant imparium circulo-
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            rum ſegmenta NBV, Nbv; </s>
            <s xml:id="echoid-s2872" xml:space="preserve">quorum axis AD; </s>
            <s xml:id="echoid-s2873" xml:space="preserve">& </s>
            <s xml:id="echoid-s2874" xml:space="preserve">in hoc circulo-
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            rum centra C, c; </s>
            <s xml:id="echoid-s2875" xml:space="preserve">conſtat ut minoris peripheriam Nbv extra majoris
              <lb/>
            NBV jacere; </s>
            <s xml:id="echoid-s2876" xml:space="preserve">ità majoris centrum C infra minoris centrum c ex-
              <lb/>
              <note position="right" xlink:label="note-0069-01" xlink:href="note-0069-01a" xml:space="preserve">Fig. 69.</note>
            iſtere. </s>
            <s xml:id="echoid-s2877" xml:space="preserve">biſecentur jam Semidiametri CB, cb in Z, z; </s>
            <s xml:id="echoid-s2878" xml:space="preserve">ducantúrque
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            tangentes BT, bt; </s>
            <s xml:id="echoid-s2879" xml:space="preserve">bíſque ductæ CN, cN occurrant punctis E, e;
              <lb/>
            </s>
            <s xml:id="echoid-s2880" xml:space="preserve">denuò radii PN axi paralleli ſit ad peripheriam NBV reflexus NK; </s>
            <s xml:id="echoid-s2881" xml:space="preserve">
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            ad ipſam verò Nbv ſit ejuſdem reflexus Nk; </s>
            <s xml:id="echoid-s2882" xml:space="preserve">liquidiſſimè jam patet
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            quòd ſit Ne &</s>
            <s xml:id="echoid-s2883" xml:space="preserve">gt; </s>
            <s xml:id="echoid-s2884" xml:space="preserve">NE; </s>
            <s xml:id="echoid-s2885" xml:space="preserve">hoc eſt quòd dupla zk major ſit duplâ ZK; </s>
            <s xml:id="echoid-s2886" xml:space="preserve">
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            adeóque ſimpla zk major ſimplâ ZK. </s>
            <s xml:id="echoid-s2887" xml:space="preserve">majoris itaque Sphæræ por-
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            tio ſtrictiores intra terminos illabentem lucem cogit; </s>
            <s xml:id="echoid-s2888" xml:space="preserve">adeóque po-
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            tentiùs operatur; </s>
            <s xml:id="echoid-s2889" xml:space="preserve">eâdemque de cauſa rem objectam illuſtriù@ </s>
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