Ibn-al-Haitam, al-Hasan Ibn-al-Hasan; Witelo; Risner, Friedrich, Opticae thesavrvs Alhazeni Arabis libri septem, nunc primùm editi. Eivsdem liber De Crepvscvlis & Nubium ascensionibus. Item Vitellonis Thuvringopoloni Libri X. Omnes instaurati, figuris illustrati & aucti, adiectis etiam in Alhazenum commentarijs, a Federico Risnero, 1572

List of thumbnails

< >
241
241 (235) 		242
242 (236)
243
243 (237) 		244
244 (238)
245
245 (239) 		246
246 (240)
247
247 (241) 		248
248 (242)
249
249 (243) 		250
250 (244)
< >
page |< < (243) of 778 > >|
    <echo version="1.0RC">
      <text xml:lang="lat" type="free">
        <div xml:id="echoid-div562" type="section" level="0" n="0">
          <p>
            <s xml:id="echoid-s17132" xml:space="preserve">
              <pb o="243" file="0249" n="249" rhead="OPTICAE LIBER VII."/>
            æqualem.</s>
            <s xml:id="echoid-s17133" xml:space="preserve"> Et ſuperficies circuli medij tranſit etiã per centrũ ſphęræ uitreæ in omnibus experimen-
              <lb/>
            tationibus uitri.</s>
            <s xml:id="echoid-s17134" xml:space="preserve"> Ergo eſt perpẽdicularis ſuper ſuperficiẽ uitri ſphæricã.</s>
            <s xml:id="echoid-s17135" xml:space="preserve"> Lux ergo, quę extẽditur in
              <lb/>
            aere, & refringitur in corpore uitri apud extenſionẽ eius in aere, poſtquã iterũ refringitur in uitro,
              <lb/>
            ſemper eſt in ſuperficie perpẽdiculari ſuper ſuperficiẽ uitri.</s>
            <s xml:id="echoid-s17136" xml:space="preserve"> Et ſemper refractio eius erit ad partem
              <lb/>
            perpẽdicularis, exeũtis à loco refractionis ſuper ſuperficiẽ uitri, ſiue ſuperficies uitri fuerit æqualis,
              <lb/>
            ſiue ſphęrica.</s>
            <s xml:id="echoid-s17137" xml:space="preserve"> Itẽ declaratũ eſt etiã, quòd linea, quę trãſit per duo cẽtra foraminũ, cũ fuerit perpẽdi-
              <lb/>
            cularis ſuք ſuperficiẽ uitri, & extẽſa fuerit in corpus uitri ſecundũ rectitudinẽ, & ſuperficies ſphæ-
              <lb/>
            rica fuerit ex parte foraminũ, & fuerit hęc linea, ſcilicet quę trãſit per centra duorũ foraminũ, decli-
              <lb/>
            nãs ſuper ſuperficiẽ uitri æqualẽ, & trãſiuerit per centrũ uitri, & refracta fuerit in corpore aeris cõ
              <lb/>
            tingẽtis ſuperficiẽ uitri æqualẽ, & apud centrũ uitri:</s>
            <s xml:id="echoid-s17138" xml:space="preserve"> tũc refractio eius erit in ſuperficie circuli me-
              <lb/>
            dij, & ad contrariã partẽ illi, in qua eſt perpẽdicularis, exiẽs à cẽtro uitri ſuper ſuperficiẽ uitri æqua-
              <lb/>
            lem.</s>
            <s xml:id="echoid-s17139" xml:space="preserve"> Et declaratũ eſt etiã, quòd linea, quę trãſit per cẽtra duorũ foraminũ, cũ fuerit perpendicularis
              <lb/>
            ſuper ſuperficiẽ uitri æqualẽ, & ſi fuerit extenſa in corpore uitri ſecundũ rectitudinẽ, & ſuperficies
              <lb/>
            æqualis fuerit ex parte foraminũ, & hęc linea, ſcilicet quę trãſit per cẽtra duorũ foraminũ, fuerit ob-
              <lb/>
            liqua ſuper ſuperficiẽ uitri ſphęricã, & nõ trãſiens per centrũ eius, & fuerit refracta apud ſuperficiẽ
              <lb/>
            uitri ſphæricã in corpore aeris contingẽtis ſuperficiẽ ſphęricam:</s>
            <s xml:id="echoid-s17140" xml:space="preserve"> tũc refractio eius erit in ſuperficie
              <lb/>
            medij circuli, & ad partẽ contrariã illi, in qua eſt perpẽdicularis, exiens à loco refractionis ſuper ſu-
              <lb/>
            perficiem ſecũdi corporis.</s>
            <s xml:id="echoid-s17141" xml:space="preserve"> Et in his duobus ſitibus ſuperficies etiã medij circuli eſt perpẽdicularis
              <lb/>
            ſuper ſuperficiẽ uitri æqualẽ & ſphæricã.</s>
            <s xml:id="echoid-s17142" xml:space="preserve"> Lux ergo, quę extẽditur in corpore uitri, & refringitur in
              <lb/>
            aere, dũ extẽditur in uitro, & refringitur in aere, ſemper eſt in ſuperficie perpẽdiculari ſuper ſuper-
              <lb/>
            ficiem aeris:</s>
            <s xml:id="echoid-s17143" xml:space="preserve"> & ſemper refractio erit ad partẽ contrariam illi, in qua eſt perpẽdicularis exiens à loco
              <lb/>
            refractionis ſuք ſuperficiẽ aeris.</s>
            <s xml:id="echoid-s17144" xml:space="preserve"> Ex omnibus ergo iſtis prædeclaratis patet, quòd omnis lux refra-
              <lb/>
            cta à corpore diaphano ad aliud corpus, ſemper refringitur in ſuperficie perpẽdiculari ſuper ſuper-
              <lb/>
            ficiem ſecũdi corporis.</s>
            <s xml:id="echoid-s17145" xml:space="preserve"> Et ſi ſecundũ corpus fuerit groſsius primo:</s>
            <s xml:id="echoid-s17146" xml:space="preserve"> tũc refractio eius erit ad partem
              <lb/>
            perpẽdicularis, exeuntis à loco refractionis ſuper ſuperficiẽ ſecũdi corporis, & nõ peruenit ad per-
              <lb/>
            pendicularem.</s>
            <s xml:id="echoid-s17147" xml:space="preserve"> Et ſi ſecundũ corpus fuerit ſubtilius primo:</s>
            <s xml:id="echoid-s17148" xml:space="preserve"> refractio erit ad partẽ contrariam illi, in
              <lb/>
            qua eſt perpẽdicularis, exiens à loco refractionis ſuper ſuperficiẽ ſecundi corporis, ſecundũ diuer-
              <lb/>
            ſitatem figurarũ ſuperficierum corporũ diaphanorũ.</s>
            <s xml:id="echoid-s17149" xml:space="preserve"> Et ex his etiã patet, quòd cum lux refringitur
              <lb/>
            à corpore diaphano ad ſecundũ corpus diaphanũ, & de ſecũdo ad tertiũ:</s>
            <s xml:id="echoid-s17150" xml:space="preserve"> refringetur etiã in ſuper-
              <lb/>
            ficie tertij, ſi diaphanitas tertij differt à diaphanitate ſecũdi:</s>
            <s xml:id="echoid-s17151" xml:space="preserve"> ſi uerò tertiũ fuerit groſsius ſecũdo:</s>
            <s xml:id="echoid-s17152" xml:space="preserve"> tũc
              <lb/>
            refractio lucis erit ad partẽ perpẽdicularis exeuntis à loco refractionis ſuper ſuperficiẽ tertij:</s>
            <s xml:id="echoid-s17153" xml:space="preserve"> ſi aũt
              <lb/>
            tertiũ fuerit ſubtilius ſecũdo:</s>
            <s xml:id="echoid-s17154" xml:space="preserve"> tũc refractio lucis erit ad partẽ cõtrariã illi, in qua eſt perpẽdicularis.</s>
            <s xml:id="echoid-s17155" xml:space="preserve">
              <lb/>
            Similiter ſi lux refracta fuerit ad quartũ corpus, & ad quintum, aut ad plurá.</s>
            <s xml:id="echoid-s17156" xml:space="preserve"> Hoc aũt declarauimus
              <lb/>
            quidẽ in hoc capitulo, qualiter omnes luces refringãtur in corporibus diaphanis diuerſæ diaphani
              <lb/>
            tatis.</s>
            <s xml:id="echoid-s17157" xml:space="preserve"> Quare aũt fiat refractio in ſuperficie perpẽdiculari ſuper ſuperficiẽ corporis diaphani, hęc eſt:</s>
            <s xml:id="echoid-s17158" xml:space="preserve">
              <lb/>
            quia linea, per quã extẽditur lux in primo diaphano corpore, refringitur ad partẽ perpẽdicularis in
              <lb/>
            hac ſuperficie, ſcilicet, in qua eſt perpẽdicularis & prima linea:</s>
            <s xml:id="echoid-s17159" xml:space="preserve"> pars enim perpẽdicularis eſt in hac
              <lb/>
            ſuperficie:</s>
            <s xml:id="echoid-s17160" xml:space="preserve"> ideo refractio fit in ſuperficie perpendiculari ſuper ſuperficiem corporis diaphani.</s>
            <s xml:id="echoid-s17161" xml:space="preserve"/>
          </p>
        </div>
        <div xml:id="echoid-div564" type="section" level="0" n="0">
          <head xml:id="echoid-head490" xml:space="preserve" style="it">10. Magnitudines angulorũ refractiõis ab aere ad aquãorgano refractiõis explorare. 5 p 10.</head>
          <p>
            <s xml:id="echoid-s17162" xml:space="preserve">QVantitates autẽ angulorũ refractionis differũt ſecundũ quantitates angulorũ, quos conti-
              <lb/>
            nent prima linea, per quã extenditur lux in primo corpore, & perpẽdicularis exiens à loco
              <lb/>
            refractionis ſuper ſuperficiẽ ſecũdi corporis, ſecundũ diaphanitatem ſecũdi corporis.</s>
            <s xml:id="echoid-s17163" xml:space="preserve"> Nam
              <lb/>
            quanto magis creſcit angulus, quẽ cõtinent prima linea & perpẽdicularis, tantò creſcit angulus re-
              <lb/>
            fractionis:</s>
            <s xml:id="echoid-s17164" xml:space="preserve"> & quantò magis decreſcit ille angulus, quẽ continẽt perpẽdicularis & prima linea, tantò
              <lb/>
            decreſcit angulus refractionis.</s>
            <s xml:id="echoid-s17165" xml:space="preserve"> Sed anguli refractionũ nõ obſeruãt eandẽ proportionẽ ad angulos,
              <lb/>
            quos cõtinet prima linea cũ perpẽdiculari, ſed differũt hæ ꝓportiones in eodẽ corpore diaphano.</s>
            <s xml:id="echoid-s17166" xml:space="preserve">
              <lb/>
            Cũ ergo prima linea, per quã lux extẽditur in primo corpore, cõtinuerit cũ perpẽdiculari duos an-
              <lb/>
            gulos inæquales, in duobus diuerſis tẽporibus, aut in duobus locis diuerſis:</s>
            <s xml:id="echoid-s17167" xml:space="preserve"> tũc ꝓportio anguli re-
              <lb/>
            fractionis, quæ eſt ab angulo minore ad angulũ minorẽ, minor erit ꝓportione anguli refractionis
              <lb/>
            anguli maioris ad angulũ maiorẽ.</s>
            <s xml:id="echoid-s17168" xml:space="preserve"> Cũ ergo experimẽtator uoluerit experiri illos angulos, diuidat à
              <lb/>
            circulo medio, qui eſt in circũferentia inſtrumẽti, ex parte cẽtri foraminis, quod eſt in circũferentia
              <lb/>
            inſtrumẽti, arcum decẽ partium ex illis partibus, quibus medius circulus diuiditur 360:</s>
            <s xml:id="echoid-s17169" xml:space="preserve"> deinde ex-
              <lb/>
            trahamus à loco differẽtiæ lineã rectã, perpendicularẽ ſuper ſuperficiẽ laminæ, & copulemus extre
              <lb/>
            mitatem eius, quæ eſt in lamina, cũ centro laminæ per lineã rectã, & protrahamus ipſam in aliã par-
              <lb/>
            tem:</s>
            <s xml:id="echoid-s17170" xml:space="preserve"> deinde diuidamus in circumferẽtia medij circuli etiã arcum ſequentẽ primum, cuius quãtitas
              <lb/>
            ſit 90 partiũ:</s>
            <s xml:id="echoid-s17171" xml:space="preserve"> & ſignemus in extremitate huius arcus ſignũ.</s>
            <s xml:id="echoid-s17172" xml:space="preserve"> Linea ergo, quæ exit à centro medij cir-
              <lb/>
            culi ad hoc ſignũ, erit perpẽdicularis ſuper lineã exeuntem à centro medij circuli ad primum ſignũ,
              <lb/>
            quod eſt in circũferentia medij circuli [per 33 p 6:</s>
            <s xml:id="echoid-s17173" xml:space="preserve"> quia hæ duæ lineæ quadrantẽ totius peripheriæ
              <lb/>
            comprehẽdunt] & erit arcus reſiduus, qui eſt inter ſignũ & extremitatẽ diametri medij circuli, quę
              <lb/>
            tranſit per centra duorũ foraminũ, 80 partiũ.</s>
            <s xml:id="echoid-s17174" xml:space="preserve"> Signemus in extremitate huius diametri etiã ſignum:</s>
            <s xml:id="echoid-s17175" xml:space="preserve">
              <lb/>
            deinde ponamus inſtrumentũ in uaſe, & obſeruemus ut circumferentia uaſis ſit æquidiſtans hori-
              <lb/>
            zonti, & incipiamus experiri ab hora ortus ſolis, & infundamus in uas aquam claram, quouſq;</s>
            <s xml:id="echoid-s17176" xml:space="preserve"> per-
              <lb/>
            ueniat ad centrum laminæ, & moueamus inſtrumẽtum, donec prima linea ſignata in ſuperficie la-
              <lb/>
            minæ, contingat ſuperficiem aquæ:</s>
            <s xml:id="echoid-s17177" xml:space="preserve"> in hoc ergo ſitu linea, quę tranſit per centrũ circuli medij, æqui-
              <lb/>
            </s>
          </p>
        </div>
      </text>
    </echo>
Impressum