Barrow, Isaac, Lectiones opticae & geometricae : in quibus phaenomenon opticorum genuinae rationes investigantur, ac exponuntur: et generalia curvarum linearum symptomata declarantur

Table of contents

< >
< >
page |< < (126) of 393 > >|
    <echo version="1.0RC">
      <text xml:lang="la" type="free">
        <div xml:id="echoid-div206" type="section" level="1" n="25">
          <p>
            <s xml:id="echoid-s8170" xml:space="preserve">
              <pb o="126" file="0144" n="144" rhead=""/>
            ticas apparens, ab intervallo longiſſimè diſſito, (quod & </s>
            <s xml:id="echoid-s8171" xml:space="preserve">maximum
              <lb/>
            ſenſibile quodvis intervallum quodammodò exſuperet) apparere.
              <lb/>
            </s>
            <s xml:id="echoid-s8172" xml:space="preserve">cùm enim quò radiis minùs divergentibus attingitur objectum, eò
              <lb/>
            (ſecluſis utique prænotionibus, & </s>
            <s xml:id="echoid-s8173" xml:space="preserve">præjudiciis) longiùs abeſſe ſentia-
              <lb/>
            tur; </s>
            <s xml:id="echoid-s8174" xml:space="preserve">& </s>
            <s xml:id="echoid-s8175" xml:space="preserve">quod parallelos ad oculum radios projicit, remotiſſimè poſi-
              <lb/>
            tum æſtimetur; </s>
            <s xml:id="echoid-s8176" xml:space="preserve">exigere ratio videtur, ut quod convergentibus radiis
              <lb/>
            apprehenditur, adhuc magìs, ſi ſieri poſſet, quoad apparentiam
              <lb/>
            elongetur. </s>
            <s xml:id="echoid-s8177" xml:space="preserve">quin & </s>
            <s xml:id="echoid-s8178" xml:space="preserve">circa caſum hunc generatim inquiri poſſit, quidnam
              <lb/>
            omninò ſit, quod apparentem puncti A locum determinet, faciátque
              <lb/>
            quòd conſtanti ratione nunc propius, nunc remotius appareat; </s>
            <s xml:id="echoid-s8179" xml:space="preserve">cui
              <lb/>
            itidem dubio nihil quicquam ex hactenus dictorum _Analogia_ reſpon-
              <lb/>
            deri poſſe videtur, niſi debere punctum A perpetuò longiſſimè ſemo-
              <lb/>
            tum videri. </s>
            <s xml:id="echoid-s8180" xml:space="preserve">Verùm experientia ſecùs atteſtatur, illud pro diversâ oculi
              <lb/>
            inter puncta B, Z poſitione variè diſtans; </s>
            <s xml:id="echoid-s8181" xml:space="preserve">nunquam ſerè (ſiunquam)
              <lb/>
            longinquius ipſo A liberè ſpectato, ſubindè vero multo propinquius
              <lb/>
            adparere; </s>
            <s xml:id="echoid-s8182" xml:space="preserve">quinimò, quo oculum appellentes radii magìs convergunt
              <lb/>
            eò ſpeciem objecti propiùs accedere. </s>
            <s xml:id="echoid-s8183" xml:space="preserve">nempe, ſi puncto B admoveatur
              <lb/>
            _ocmlus,_ ſuo (ad lentem) ferè nativo in loco conſpicitur punctum A
              <lb/>
            (vel æquè diſtans, ad _ſpeculum_;) </s>
            <s xml:id="echoid-s8184" xml:space="preserve">ad O reductus oculus ejuſce ſpeciem
              <lb/>
            appropinquantem cernit; </s>
            <s xml:id="echoid-s8185" xml:space="preserve">ad P adhuc vicinius ipſum exiſtimat; </s>
            <s xml:id="echoid-s8186" xml:space="preserve">ac
              <lb/>
            ità ſenſim, donec alicubi tandem, velut ad Q, conſtituto oculo ob-
              <lb/>
            jectum ſummè propinquum apparens in meram conſuſionem incipiat
              <lb/>
            evaneſcere. </s>
            <s xml:id="echoid-s8187" xml:space="preserve">quæ ſanè cuncta rationibus atque decretis noſtris repug-
              <lb/>
            nare videntur, aut cum iis ſaltem parùm amicè conſpirant. </s>
            <s xml:id="echoid-s8188" xml:space="preserve">Neque
              <lb/>
            noſtram tantùm ſententiam pulſat hoc experimentum; </s>
            <s xml:id="echoid-s8189" xml:space="preserve">at ex æquo
              <lb/>
            cæteras quas nôrim omnes; </s>
            <s xml:id="echoid-s8190" xml:space="preserve">veterem imprimìs ac vulgatam; </s>
            <s xml:id="echoid-s8191" xml:space="preserve">noſtræ
              <lb/>
            præ reliquis aſſinem ità convellere videtur, ut ejus vi coactus doctiſſi-
              <lb/>
            mus _A. </s>
            <s xml:id="echoid-s8192" xml:space="preserve">Tacquetus_ iſti principio (cui penè ſoli totam inædificaverat
              <lb/>
            _Catoptricam_ ſuam) ceu inſido ac inconſtanti renunciarit, adeoque
              <lb/>
            ſuam ipſe doctrinam labefactârit; </s>
            <s xml:id="echoid-s8193" xml:space="preserve">id tamen, opinor, minimè facturus,
              <lb/>
            ſi rem totam inſpexiſſet penitiùs, atque difficultatis fundum attigiſſet. </s>
            <s xml:id="echoid-s8194" xml:space="preserve">
              <lb/>
            Apud me verò non ità pollet hæc, nec eoúſque præpollebit ulla diffi-
              <lb/>
            cultas, ut ab iis quæ manifeſtè rationi conſentanea video, diſcedam; </s>
            <s xml:id="echoid-s8195" xml:space="preserve">
              <lb/>
            præſertim quum ut hîc accidit, ejuſmodi difficultas in ſingularis cujus
              <lb/>
            piam casûs diſparitate fundetur. </s>
            <s xml:id="echoid-s8196" xml:space="preserve">nimirum in præſente caſu peculiare
              <lb/>
            quiddam, naturæ ſubtilitati involutum, deliteſcit, ægrè fortaſsìs, niſi
              <lb/>
            perfectius explorato videndi modo, detegendum. </s>
            <s xml:id="echoid-s8197" xml:space="preserve">circa quod nil, fateor,
              <lb/>
            hactenus excogitare potui, quod adblandiretur animo meo, nedum planè
              <lb/>
            ſatisfaceret. </s>
            <s xml:id="echoid-s8198" xml:space="preserve">Vobis itaque nodum hunc, utinam feliciore conatu, re-
              <lb/>
            ſolvendum committo. </s>
            <s xml:id="echoid-s8199" xml:space="preserve">Ità demum, _Auditores Optimi, Valeatis._</s>
            <s xml:id="echoid-s8200" xml:space="preserve"/>
          </p>
        </div>
      </text>
    </echo>
Impressum