Blancanus, Josephus, Sphaera mvndi, sev cosmographia demonstratiua , ac facile methodo tradita : in qua totius Mundi fabrica, vna cum nouis, Tychonis, Kepleri, Galilaei, aliorumq' ; Astronomorum adinuentis continentur ; Accessere I. Breuis introductio ad geographiam. II. Apparatus ad mathematicarum studium. III. Echometria, idest Geometrica tractatio de Echo. IV. Nouum instrumentum ad Horologia
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    <echo version="1.0RC">
      <text xml:lang="la" type="free">
        <div xml:id="echoid-div282" type="section" level="1" n="193">
          <pb o="138" file="0160" n="165" rhead="De Mundi Fabrica,"/>
        </div>
        <div xml:id="echoid-div283" type="section" level="1" n="194">
          <head xml:id="echoid-head208" style="it" xml:space="preserve">Illuminatie
            <unsure/>
          , & Vmbra Veneris. Cap. II.</head>
          <p>
            <s xml:id="echoid-s12784" xml:space="preserve">IInter admiranda, quæ nuper ope Teleſcopij cælitus innotuerunt, illud ſane pulcherrimũ de Veneris illu-
              <lb/>
            minatione; </s>
            <s xml:id="echoid-s12785" xml:space="preserve">qua non vnicam in cælo Lunam, ſed duas in cælo Lunas rimatus, atque miratus eſt mundus:
              <lb/>
            </s>
            <s xml:id="echoid-s12786" xml:space="preserve">illuminatur enim à Sole, ita vt modo falcata, modo ſemiplena, modo plena lumine conſpiciatur, non aliter ac
              <lb/>
            Luna, quamuis alio @rdine; </s>
            <s xml:id="echoid-s12787" xml:space="preserve">quæ illuminationum ſeries, & </s>
            <s xml:id="echoid-s12788" xml:space="preserve">modus in apoſita figura clarior euadet. </s>
            <s xml:id="echoid-s12789" xml:space="preserve">in qua ocu-
              <lb/>
            lus noſter aſpiciens haſce illuminationes ſit vbi O, Sol ſit vbi S. </s>
            <s xml:id="echoid-s12790" xml:space="preserve">gyruſ-
              <lb/>
              <figure xlink:label="fig-0160-01" xlink:href="fig-0160-01a" number="96">
                <image file="0160-01" xlink:href="http://echo.mpiwg-berlin.mpg.de/zogilib?fn=/permanent/library/xxxxxxxx/figures/0160-01"/>
              </figure>
            que Solis proprius ſit X S Y. </s>
            <s xml:id="echoid-s12791" xml:space="preserve">Epicyclus ſiue gyrus Veneris circa Solem,
              <lb/>
            ſit quem vides; </s>
            <s xml:id="echoid-s12792" xml:space="preserve">in cuius varijs locis depicta eſt Veneris ſphæra, eodem
              <lb/>
            modo ſemper illuminata; </s>
            <s xml:id="echoid-s12793" xml:space="preserve">verum non eodem modo ſe oculo in O, ſito
              <lb/>
            apparens. </s>
            <s xml:id="echoid-s12794" xml:space="preserve">duæ lineæ O X. </s>
            <s xml:id="echoid-s12795" xml:space="preserve">O Y. </s>
            <s xml:id="echoid-s12796" xml:space="preserve">tangentes epicyclum diſtant à linea
              <lb/>
            O S A. </s>
            <s xml:id="echoid-s12797" xml:space="preserve">ipſum bifariam ſecante, hinc inde per gr. </s>
            <s xml:id="echoid-s12798" xml:space="preserve">48. </s>
            <s xml:id="echoid-s12799" xml:space="preserve">ideſt, arcus S X,
              <lb/>
            S Y. </s>
            <s xml:id="echoid-s12800" xml:space="preserve">ſunt gra. </s>
            <s xml:id="echoid-s12801" xml:space="preserve">48. </s>
            <s xml:id="echoid-s12802" xml:space="preserve">ſinguli, iuxta maximam Veneris à Sole digreſſionem.
              <lb/>
            </s>
            <s xml:id="echoid-s12803" xml:space="preserve">quando igitur Venus incipit eſſe Veſpertinus Heſperus, quando ſcili-
              <lb/>
            cet poſt Solis occaſum primo apparet, tunc per Teleſcopium viſa, rotun
              <lb/>
            da ſeu plena apparet, quia eſt in B. </s>
            <s xml:id="echoid-s12804" xml:space="preserve">in quo ſitu totam ſui illuminationem
              <lb/>
            oculo in O. </s>
            <s xml:id="echoid-s12805" xml:space="preserve">ſito. </s>
            <s xml:id="echoid-s12806" xml:space="preserve">videndam obuertit. </s>
            <s xml:id="echoid-s12807" xml:space="preserve">poſtea recedens à Sole rotundita-
              <lb/>
            tem paulatim amittit, quia deſcendit ad C. </s>
            <s xml:id="echoid-s12808" xml:space="preserve">vbi amplius tota illuminatio
              <lb/>
            ab oculo videri nequit, & </s>
            <s xml:id="echoid-s12809" xml:space="preserve">propterea gibboſa apparet. </s>
            <s xml:id="echoid-s12810" xml:space="preserve">deinde dimidia
              <lb/>
            ſeu ſemiplena apparet, quoniam ad D. </s>
            <s xml:id="echoid-s12811" xml:space="preserve">deuoluta eſt, vbi dimidiam ſui
              <lb/>
            illuminationem oculo exhibet. </s>
            <s xml:id="echoid-s12812" xml:space="preserve">dehinc in E. </s>
            <s xml:id="echoid-s12813" xml:space="preserve">delapſa corniculata cerni-
              <lb/>
            tur, quia oculus O. </s>
            <s xml:id="echoid-s12814" xml:space="preserve">paruam illuminationis partem, eamque falcatam vi-
              <lb/>
            dere poteſt, ſicuti etiam in Luna explicatum eſt. </s>
            <s xml:id="echoid-s12815" xml:space="preserve">In A. </s>
            <s xml:id="echoid-s12816" xml:space="preserve">& </s>
            <s xml:id="echoid-s12817" xml:space="preserve">F. </s>
            <s xml:id="echoid-s12818" xml:space="preserve">videri ne-
              <lb/>
            quit ob nimium Solis fulgorem, eaſdem apparentias alterum epicycli
              <lb/>
            ſemicirculum ingrediens, vbi ex Heſpero euaſit Lucifer, & </s>
            <s xml:id="echoid-s12819" xml:space="preserve">manè præ-
              <lb/>
            fulget, reſtituit; </s>
            <s xml:id="echoid-s12820" xml:space="preserve">ſed inuerſo ordine, nam in G. </s>
            <s xml:id="echoid-s12821" xml:space="preserve">corniculata, in H. </s>
            <s xml:id="echoid-s12822" xml:space="preserve">dimi-
              <lb/>
            diaca, in I. </s>
            <s xml:id="echoid-s12823" xml:space="preserve">gibboſa, in K. </s>
            <s xml:id="echoid-s12824" xml:space="preserve">plena conſpicitur: </s>
            <s xml:id="echoid-s12825" xml:space="preserve">vt conſideranti patere poteſt; </s>
            <s xml:id="echoid-s12826" xml:space="preserve">oculus enim videt eam ſolam par-
              <lb/>
            tem illuminationis, quæ continetur literis e r p. </s>
            <s xml:id="echoid-s12827" xml:space="preserve">quæ falcata apparet, quia eſt in ſuperficie ſphærica, eamq; </s>
            <s xml:id="echoid-s12828" xml:space="preserve">
              <lb/>
            præcingit. </s>
            <s xml:id="echoid-s12829" xml:space="preserve">quæ omnia ſaluantur perfectè, ſi dicamus Venerem circa Solem circumcurſare, vt in figura oſten-
              <lb/>
            ditur. </s>
            <s xml:id="echoid-s12830" xml:space="preserve">Idem hac iucunda experientia confirmari, ac ritè percipi poteſt. </s>
            <s xml:id="echoid-s12831" xml:space="preserve">Cape ſphæram aliquam terſam, eam-
              <lb/>
            que circa lumen aliquod paulatim circunducas, ita vt oculus tuus extra gyrum ſit, gyrus porrò hic debet eſſe
              <lb/>
            in plano imaginario per oculum tuum tranſeunte. </s>
            <s xml:id="echoid-s12832" xml:space="preserve">in hac igitur ſphæræ gyratione iucundè contemplaberis
              <lb/>
            has omnes Veneris illuminationes: </s>
            <s xml:id="echoid-s12833" xml:space="preserve">hoc eodem modo Mercurium illuminari exiſtimo. </s>
            <s xml:id="echoid-s12834" xml:space="preserve">Hac Veneris illumi-
              <lb/>
            natione ſic proſpecta @ſatisfacere poſſumus cuidam quæſtioni, quæ priores Aſtronomos vrgebat; </s>
            <s xml:id="echoid-s12835" xml:space="preserve">cur nimi-
              <lb/>
            rum Vcnus quando circa ima epicycli verſatur, nobiſque propior eſt, minor appareat, quam cum ſublimior
              <lb/>
            fertur, contrarium enim accidere deberet, quæ enim propria ſunt, maiora videntur. </s>
            <s xml:id="echoid-s12836" xml:space="preserve">Reſpondemus igitur
              <lb/>
            ideo minorem videri, quia non tota videtur, ſed minor eius pars illuminata, vti modo explicatum eſt; </s>
            <s xml:id="echoid-s12837" xml:space="preserve">& </s>
            <s xml:id="echoid-s12838" xml:space="preserve">ap-
              <lb/>
            paret inſpicientibus etiam per Teleſcopium. </s>
            <s xml:id="echoid-s12839" xml:space="preserve">quod ſcilicet quando eſt infra Solem, parum illuminationis eius
              <lb/>
            cernitur.</s>
            <s xml:id="echoid-s12840" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s12841" xml:space="preserve">Notandum præterea ſolam Venerem inter omnes planetas, luminaria, interdiu non raro percommodè
              <lb/>
            videri, quod ei accidit, cum plenam ſui illuminationem nobis exhibet, ac ſimul extra Solis fulgorem euaſit:
              <lb/>
            </s>
            <s xml:id="echoid-s12842" xml:space="preserve">adeo enim magna aliquando conſpicitur, vt vulgus eam, aut cometam, aut, nouam aliquam ſtellam exiſtimet
              <lb/>
            illud tandem ei proprium ex quinque planetis, vt noctu cum pleno iubare fulget, corpora ab ipſa colluſtra-
              <lb/>
            ta, vmbras efficiant: </s>
            <s xml:id="echoid-s12843" xml:space="preserve">Porrò locus Plinij ex lib. </s>
            <s xml:id="echoid-s12844" xml:space="preserve">2. </s>
            <s xml:id="echoid-s12845" xml:space="preserve">cap. </s>
            <s xml:id="echoid-s12846" xml:space="preserve">7. </s>
            <s xml:id="echoid-s12847" xml:space="preserve">dignus eſt qui hunc referatur; </s>
            <s xml:id="echoid-s12848" xml:space="preserve">Solem, inquit, ambit
              <lb/>
            ingens ſydus appellatum Veneris, alterno motu vagum, ipſis cognominibus æmulum Solis, & </s>
            <s xml:id="echoid-s12849" xml:space="preserve">Lunæ; </s>
            <s xml:id="echoid-s12850" xml:space="preserve">præ-
              <lb/>
            ueniens quippe, & </s>
            <s xml:id="echoid-s12851" xml:space="preserve">ante matutinum exoriens, Luciferi nomen accepit, vt Sol alter diem maturans: </s>
            <s xml:id="echoid-s12852" xml:space="preserve">contra
              <lb/>
            ab occaſu refulgens nuncupatur Veſper, aut prorogans lucem, vicemque Lunæ reddens. </s>
            <s xml:id="echoid-s12853" xml:space="preserve">quam eius natu-
              <lb/>
            ram Pythagoras Samius primus depræhendit Olympiade circiter 42. </s>
            <s xml:id="echoid-s12854" xml:space="preserve">qui fuit Vrbis Romæ 142. </s>
            <s xml:id="echoid-s12855" xml:space="preserve">Iam ma-
              <lb/>
            gnitudine extra cuncta alia ſydera eſt claritas quidem tantæ, vt vnius huius ſtellæ radijs vmbræ reddantur. </s>
            <s xml:id="echoid-s12856" xml:space="preserve">
              <lb/>
            hæc ille.</s>
            <s xml:id="echoid-s12857" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s12858" xml:space="preserve">Poſtremo non eſt prætereunda cõſideratio vmbræ ipſius Veneris quanta videlicet ſit; </s>
            <s xml:id="echoid-s12859" xml:space="preserve">eam ſic habebimus,
              <lb/>
            conſtructa figura in qua veræ ſint corporum Solis, & </s>
            <s xml:id="echoid-s12860" xml:space="preserve">Veneris necnon diſtantiæ proportiones, ductis duabus
              <lb/>
            lineis tangentibus vtrumque, exurget vmbra conica Veneris, ex parte concurſus linearum tangentium,
              <lb/>
            quemadmodum in Luna factum eſt: </s>
            <s xml:id="echoid-s12861" xml:space="preserve">ſed, & </s>
            <s xml:id="echoid-s12862" xml:space="preserve">alio modo, quo vſi ſumus in inueſtiganda vmbra terræ, & </s>
            <s xml:id="echoid-s12863" xml:space="preserve">Mer-
              <lb/>
            curij, cuius demonſtrationem, & </s>
            <s xml:id="echoid-s12864" xml:space="preserve">figuram habes pag. </s>
            <s xml:id="echoid-s12865" xml:space="preserve">78. </s>
            <s xml:id="echoid-s12866" xml:space="preserve">duo tamen ſupponenda ſunt, quæ paulò poſt pro-
              <lb/>
            babimus: </s>
            <s xml:id="echoid-s12867" xml:space="preserve">diſtantia nimirum Solis, & </s>
            <s xml:id="echoid-s12868" xml:space="preserve">Veneris; </s>
            <s xml:id="echoid-s12869" xml:space="preserve">necnon vtriuſque diametrorum proportio, diſtant erit ſemi-
              <lb/>
            diam. </s>
            <s xml:id="echoid-s12870" xml:space="preserve">terræ 855. </s>
            <s xml:id="echoid-s12871" xml:space="preserve">diameter Solis ad diametrum Veneris eſt, ſicuti 26. </s>
            <s xml:id="echoid-s12872" xml:space="preserve">ad {30/11}. </s>
            <s xml:id="echoid-s12873" xml:space="preserve">vt igitur eſt 23 {3/11} ad 2 {8/11}. </s>
            <s xml:id="echoid-s12874" xml:space="preserve">ſic fiat
              <lb/>
            855. </s>
            <s xml:id="echoid-s12875" xml:space="preserve">ad aliud per auream regulam, reperieſque 102. </s>
            <s xml:id="echoid-s12876" xml:space="preserve">fere; </s>
            <s xml:id="echoid-s12877" xml:space="preserve">quare Veneris vmbra totidem terræ ſemidiam. </s>
            <s xml:id="echoid-s12878" xml:space="preserve">pro-
              <lb/>
            te
              <unsure/>
            nditur: </s>
            <s xml:id="echoid-s12879" xml:space="preserve">qua propter nullo pacto Lunam obumbrare poterit, quæ infra ipſam pluſquam ducentis ſemidia-
              <lb/>
            metris a
              <unsure/>
            Sole gyrat.</s>
            <s xml:id="echoid-s12880" xml:space="preserve"/>
          </p>
        </div>
      </text>
    </echo>
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