Benedetti, Giovanni Battista de, Io. Baptistae Benedicti ... Diversarvm specvlationvm mathematicarum, et physicarum liber : quarum seriem sequens pagina indicabit ; [annotated and critiqued by Guidobaldo Del Monte]

Page concordance

< >
Scan Original
91 79
92 80
93 81
94 82
95 89
96 84
97 85
98 96
99 87
100 88
101 89
102 90
103 91
104 92
105 93
106 94
107 95
108 96
109 97
110 98
111 99
112 100
113 101
114 102
115 103
116 104
117 105
118 106
119 107
120 108
< >
page |< < (335) of 445 > >|
    <echo version="1.0">
      <text type="book" xml:lang="la">
        <div xml:id="echoid-div7" type="body" level="1" n="1">
          <div xml:id="echoid-div477" type="chapter" level="2" n="6">
            <div xml:id="echoid-div642" type="section" level="3" n="28">
              <div xml:id="echoid-div650" type="letter" level="4" n="3">
                <pb o="335" rhead="EPISTOLAE." n="347" file="0347" xlink:href="http://echo.mpiwg-berlin.mpg.de/zogilib?fn=/permanent/library/163127KK/pageimg/0347"/>
                <p>
                  <s xml:id="echoid-s4064" xml:space="preserve">Nam circa æqualitatem angulorum reflexionis & incidentiæ, iam tibi probaui
                    <lb/>
                  illud non vniuerſaliter euenire à breuitate aggregati radiorum incidentiæ reflexio-
                    <lb/>
                    <reg norm="nisque" type="simple">nisq́;</reg>
                  . </s>
                  <s xml:id="echoid-s4065" xml:space="preserve">Sed hoc naſcitur potius ab eo, quod cum radius incidentiæ non poſſit ſuper
                    <lb/>
                  ficiem corporis opaci penetrare, reflectit, vt citra ipſam
                    <reg norm="cum" type="context">cũ</reg>
                  angulo æquali ei, quem
                    <lb/>
                  faceret cum eadem ſuperficie vltra ipſam ſi tranſiuiſſet.</s>
                </p>
                <p>
                  <s xml:id="echoid-s4066" xml:space="preserve">Exempli gratia ſit
                    <var>.a.</var>
                  obiectum
                    <var>.b.</var>
                    <reg norm="autem" type="context">autẽ</reg>
                  oculus in figura
                    <var>.A.</var>
                  et
                    <var>.c.e.</var>
                  ſuperficies ipſius
                    <lb/>
                  ſpeculi
                    <var>.d.</var>
                  verò ſit punctum ipſius ſuperficiei, à quo ad oculum reflectitur imago ip-
                    <lb/>
                    <figure xlink:label="fig-0347-01" xlink:href="fig-0347-01a" number="374">
                      <image file="0347-01" xlink:href="http://echo.mpiwg-berlin.mpg.de/zogilib?fn=/permanent/library/163127KK/figures/0347-01"/>
                    </figure>
                  ſius
                    <var>.a</var>
                  . </s>
                  <s xml:id="echoid-s4067" xml:space="preserve">Nunc ſi radius
                    <var>.a.d.</var>
                  incidentiæ, recta
                    <lb/>
                  incederet ſub
                    <var>.c.e.</var>
                  efficeret angulum
                    <var>.e.d.h.</var>
                    <lb/>
                  æqualem angulo
                    <var>.c.d.a.</var>
                  eius contrapoſito,
                    <lb/>
                  ſed quia impeditur ipſæ radius ab opacitate
                    <lb/>
                  ipſius ſpeculi
                    <var>.c.e.</var>
                  ne vlterius incedat, propte
                    <lb/>
                  rea reflectitur ab ipſa ſuperficie ſpeculi, con-
                    <lb/>
                  ſtituens cum ipſa angulum
                    <var>.e.d.b.</var>
                  æqualem
                    <lb/>
                  angulo
                    <var>.e.d.h.</var>
                  ſed quia angulus
                    <var>.c.d.a.</var>
                  eſt
                    <reg norm="etiam" type="context">etiã</reg>
                    <lb/>
                  ęqualis ipſi angulo
                    <var>.e.d.h.</var>
                  propterea angulus
                    <var>.e.d.b.</var>
                  ęqualis exiſtit angulo
                    <var>.c.d.</var>
                  a; </s>
                  <s xml:id="echoid-s4068" xml:space="preserve">per
                    <lb/>
                  accidens igitur ſequitur
                    <var>.a.d.</var>
                  et
                    <var>.d.b.</var>
                  ſimul ſumptas, breuiorem facere longiludinem
                    <lb/>
                  omni alia, quæ ab ipſa ſuperficie
                    <var>.c.e.</var>
                  ad eadem puncta
                    <var>.a.b.</var>
                  ducta eſſet, </s>
                  <s xml:id="echoid-s4069" xml:space="preserve">quare natu-
                    <lb/>
                  ræintentio eſt efficere angulum
                    <var>.e.d.b.</var>
                  æqualem angulo
                    <var>.e.d.h.</var>
                  vnde ex accidenti po
                    <lb/>
                  ſtea ſequitur, ipſum æqualem eſſe angulo
                    <var>.c.d.a.</var>
                  & deinde
                    <reg norm="quod" type="wordlist">qđ</reg>
                  lineæ
                    <var>.a.d.</var>
                  et
                    <var>.d.b.</var>
                  con-
                    <lb/>
                  ſtituant longitudinem breuiorem. </s>
                  <s xml:id="echoid-s4070" xml:space="preserve">Quare illud quod omnes putabant eſſe primum
                    <lb/>
                  & perſe, vltimum eſt, & exaccidenti.</s>
                </p>
                <p>
                  <s xml:id="echoid-s4071" xml:space="preserve">Quare vero ſuperficies, quæ vocatur reflexionis, in qua ſunt duæ lineę, hoc eſt
                    <lb/>
                  incidentię,
                    <reg norm="reflexionisque" type="simple">reflexionisq́;</reg>
                  , ſemper ſit perpendicularis ſuperficiei ipſius ſpeculi: </s>
                  <s xml:id="echoid-s4072" xml:space="preserve">Hæc
                    <lb/>
                  eſt ratio, quia cum quilibet radius incidentiæ, perpendicularis ipſi ſuperficiei ſpe-
                    <lb/>
                  culi, in ſeipſo reflectit, ex ijſdem dictis rationibus, hoc eſt, quia cum tali angulo vult
                    <lb/>
                  reflecti, cum quali tranſiret, ita etiam purandum eſt, quodradius incidens obliquus,
                    <lb/>
                  cum in ſeipſum non poſſit redire, quia non eſt perpendicularis ſuperficiei ſpeculi,
                    <lb/>
                  reflectitur tamen per planum erectum ipſi ſuperficiei ſpeculi, vt in eo, cui magis re-
                    <lb/>
                  ſiſtit ſuperficies corporis opaci, quàm alicui alij plano ipſius infiniti inclinatorum
                    <lb/>
                  planorum, ab vtraque parte ipſius plani perpendicularis, quod vnum etiam tan-
                    <lb/>
                  tummodo eſt, & in quo, radius maiorem vim obtinet reflectendi, ſeu in eo, in quo
                    <lb/>
                  radius ipſe cum maiori reſiſtentia repercutitur à ſuperficie corporis opaci.</s>
                </p>
                <p>
                  <s xml:id="echoid-s4073" xml:space="preserve">Poſtremo
                    <reg norm="ſciendum" type="context context">ſciẽdũ</reg>
                  vnde oriatur,
                    <reg norm="quod" type="simple">ꝙ</reg>
                  rei viſibilis imago, à ſpeculo plano reflexa, ſem
                    <lb/>
                  per in catheto incidentiæ videatur.</s>
                </p>
                <p>
                  <s xml:id="echoid-s4074" xml:space="preserve">Pro cuius rei ratione cognoſcendum primò eſt, quo modo fit perfecta
                    <reg norm="ſimplexque" type="simple">ſimplexq́;</reg>
                    <lb/>
                  viſio, & non reflexa, deinde proſequemur ad reliqua huius tertiæ propoſitionis.</s>
                </p>
                <p>
                  <s xml:id="echoid-s4075" xml:space="preserve">Animaduertendum igitur eſt, quod
                    <reg norm="quotieſcunque" type="simple">quotieſcunq;</reg>
                  obiectum aliquod viſibile aſpi
                    <lb/>
                  cimus, nos nunquam perfectè illud comprehendere poſſumus, niſi in puncto con-
                    <lb/>
                  curſus, ſeu interſectionis axium viſualium, ſeu radialium ( vt ita loquar )
                    <reg norm="quam" type="context">quã</reg>
                    <reg norm="inter- ſectionem" type="context">inter-
                      <lb/>
                    ſectionẽ</reg>
                  , nos efficimus ope reuolutionis oculorum
                    <reg norm="adinuicem" type="context">adinuicẽ</reg>
                  , hoc eſt voluendo vnum
                    <lb/>
                  verſus alium, ita vt in ſitu ipſius obiecti, ſeinuicem ſecent axes iam dicti, </s>
                  <s xml:id="echoid-s4076" xml:space="preserve">tunc enim
                    <lb/>
                  vtroque oculo mediante, exacte rem perſpicimus, cęteris .8. circunſtantijs non ob-
                    <lb/>
                  ſtantibus.</s>
                </p>
                <p>
                  <s xml:id="echoid-s4077" xml:space="preserve">Vnde ſtantibus oculis in tali ſitu, altero reſpectu alterius, ſi eorum alter tectus;
                    <lb/>
                  </s>
                  <s xml:id="echoid-s4078" xml:space="preserve">ſeu velatus fuerit, tune alio tantummodo oculo mediante, videbimus obiectum,
                    <lb/>
                  in ea diſtantia, exactius, quam in quauis alia propinquiori, & remotiori.</s>
                </p>
              </div>
            </div>
          </div>
        </div>
      </text>
    </echo>