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

Page concordance

< >
Scan Original
51 45
52 46
53 47
54 48
55 49
56 50
57 51
58 52
59 53
60 54
61 55
62 56
63 57
64 58
65 59
66 60
67 61
68 62
69 63
70 64
71 65
72 66
73 67
74 68
75 69
76 70
77 71
78 72
79 73
80 74
< >
page |< < (157) of 778 > >|
    <echo version="1.0RC">
      <text xml:lang="lat" type="free">
        <div xml:id="echoid-div365" type="section" level="0" n="0">
          <p>
            <s xml:id="echoid-s9952" xml:space="preserve">
              <pb o="157" file="0163" n="163" rhead="OPTICAE LIBER V."/>
            culum [per 4 th.</s>
            <s xml:id="echoid-s9953" xml:space="preserve"> 1 conicorũ Apollonij] ꝗ ſit p g:</s>
            <s xml:id="echoid-s9954" xml:space="preserve"> & ducãtur lineę a g, b g, a b:</s>
            <s xml:id="echoid-s9955" xml:space="preserve"> & à pũcto g ducatur ad
              <lb/>
            cẽtrũ circuli linea:</s>
            <s xml:id="echoid-s9956" xml:space="preserve"> q̃ ſit g t:</s>
            <s xml:id="echoid-s9957" xml:space="preserve"> & uertex pyramidis ſit e:</s>
            <s xml:id="echoid-s9958" xml:space="preserve"> à quo ducatur axis:</s>
            <s xml:id="echoid-s9959" xml:space="preserve"> ꝗ erit e t.</s>
            <s xml:id="echoid-s9960" xml:space="preserve"> [per 3 d 1 coni.</s>
            <s xml:id="echoid-s9961" xml:space="preserve"> A-
              <lb/>
            pol.</s>
            <s xml:id="echoid-s9962" xml:space="preserve">] Et ducatur [per 12 p 11] perpẽdicularis ſuper ſuperficiẽ, cõtingentẽ fpeculũ in pũcto g:</s>
            <s xml:id="echoid-s9963" xml:space="preserve"> q̃ ſit h
              <lb/>
            g:</s>
            <s xml:id="echoid-s9964" xml:space="preserve"> q̃ cũ diuidat angulũ a g b per æqualia, [per 13 n 4] cadet ſuper a b:</s>
            <s xml:id="echoid-s9965" xml:space="preserve"> pũctũ caſus ſit z.</s>
            <s xml:id="echoid-s9966" xml:space="preserve"> Et à uertice py
              <lb/>
            ramidis ducatur linea lõgitudinis ſpeculi ad punctũ g:</s>
            <s xml:id="echoid-s9967" xml:space="preserve"> [educto nẽpe plano per axem, & perrectã à
              <lb/>
            puncto g, cũ ipſo utlibet cõcurrentẽ:</s>
            <s xml:id="echoid-s9968" xml:space="preserve"> cõmunis enim fectio huius plani & conicæ ſuperficiei erit la-
              <lb/>
            tus coni, ք 18 d 11, uel 3 th.</s>
            <s xml:id="echoid-s9969" xml:space="preserve"> 1 coni.</s>
            <s xml:id="echoid-s9970" xml:space="preserve"> Apol.</s>
            <s xml:id="echoid-s9971" xml:space="preserve">] quę ſit e g:</s>
            <s xml:id="echoid-s9972" xml:space="preserve"> cui lineæ ducatur æquidiſtãs à pũcto a:</s>
            <s xml:id="echoid-s9973" xml:space="preserve"> [per 31 p 1]
              <lb/>
            quę neceſſariò ſecabit ſuperficiẽ circuli g p:</s>
            <s xml:id="echoid-s9974" xml:space="preserve"> [ſi enim circulũ cũ diametro infinitè extẽſum cogites:</s>
            <s xml:id="echoid-s9975" xml:space="preserve">
              <lb/>
            diameter ſecãs e g conilatus, ſecabit etiã rectã lateri parallelã, per lẽma Procli ad 29 p 1.</s>
            <s xml:id="echoid-s9976" xml:space="preserve"> Quare eadẽ
              <lb/>
            parallela circulũ ipſum quoq;</s>
            <s xml:id="echoid-s9977" xml:space="preserve"> ſecabit] ſecet in pũcto n:</s>
            <s xml:id="echoid-s9978" xml:space="preserve"> & ſit n a.</s>
            <s xml:id="echoid-s9979" xml:space="preserve"> Similiter à pũcto b ducatur æqui-
              <lb/>
            diſtãs eidẽ e g, ſcilicet b m:</s>
            <s xml:id="echoid-s9980" xml:space="preserve"> quę ſecet ſuperficiẽ p g in pũcto m.</s>
            <s xml:id="echoid-s9981" xml:space="preserve"> Et à pũcto n ducatur ę ꝗ diſtãs ipſi g t:</s>
            <s xml:id="echoid-s9982" xml:space="preserve">
              <lb/>
            quę ſit n f:</s>
            <s xml:id="echoid-s9983" xml:space="preserve"> & ducãtur lineæ n g, m g, n m.</s>
            <s xml:id="echoid-s9984" xml:space="preserve"> Palàm, quòd t g ſecabit m n:</s>
            <s xml:id="echoid-s9985" xml:space="preserve"> [per lẽma Procli ad 29 p 1] ſe-
              <lb/>
            cetin pũcto q.</s>
            <s xml:id="echoid-s9986" xml:space="preserve"> Palàm etiã, quòd m g ſecabit n f:</s>
            <s xml:id="echoid-s9987" xml:space="preserve"> cũ ſecet ei æquidiſtãtẽ:</s>
            <s xml:id="echoid-s9988" xml:space="preserve"> ſit pũctũ ſectionis f.</s>
            <s xml:id="echoid-s9989" xml:space="preserve"> Et à pun
              <lb/>
            cto a ducatur æquidiſtãs h z:</s>
            <s xml:id="echoid-s9990" xml:space="preserve"> quę ſit a l.</s>
            <s xml:id="echoid-s9991" xml:space="preserve"> Palàm [per lẽma Procli ad 29 p 1] quòd b g cõcurret cũ a l:</s>
            <s xml:id="echoid-s9992" xml:space="preserve">
              <lb/>
            ſit cõcurſus l.</s>
            <s xml:id="echoid-s9993" xml:space="preserve"> Deinde ducatur linea cõmunis ſuperficiei,
              <lb/>
              <figure xlink:label="fig-0163-01" xlink:href="fig-0163-01a" number="89">
                <variables xml:id="echoid-variables79" xml:space="preserve">f d a e p t m f k h i g z o q n b</variables>
              </figure>
            cõtingẽti ſpeculũ in puncto g, & ſuperficiei circuli p g:</s>
            <s xml:id="echoid-s9994" xml:space="preserve"> q̃
              <lb/>
            ſit g o.</s>
            <s xml:id="echoid-s9995" xml:space="preserve"> Palàm [per 18 p 3] quòd erit orthogonalis ſuper
              <lb/>
            g t:</s>
            <s xml:id="echoid-s9996" xml:space="preserve"> & ſimiliter [ք 29 p 1] ſuper n f.</s>
            <s xml:id="echoid-s9997" xml:space="preserve"> Sumatur etiã linea cõ-
              <lb/>
            munis ſuperficiei, cõtingẽti ſpeculũ, & ſuperficiei reflexi
              <lb/>
            onis:</s>
            <s xml:id="echoid-s9998" xml:space="preserve"> quę ſit g d:</s>
            <s xml:id="echoid-s9999" xml:space="preserve"> q̃ quidẽ cũ ſecet g h, ſecabit a l.</s>
            <s xml:id="echoid-s10000" xml:space="preserve"> [per lẽma
              <lb/>
            Procli ad 29 p 1.</s>
            <s xml:id="echoid-s10001" xml:space="preserve">] Sit punctũ ſectionis d:</s>
            <s xml:id="echoid-s10002" xml:space="preserve"> & erit orthogo-
              <lb/>
            nalis ſuper a l.</s>
            <s xml:id="echoid-s10003" xml:space="preserve"> [Quia enim h g perpẽdicularis eſt plano,
              <lb/>
            tãgẽti ſpeculũ in pũcto reflexionis g, ք fabricationẽ:</s>
            <s xml:id="echoid-s10004" xml:space="preserve"> erit
              <lb/>
            ք 3 d 11 perpẽdicularis rectæ lineæ g d ipſam in puncto g
              <lb/>
            tãgẽti.</s>
            <s xml:id="echoid-s10005" xml:space="preserve"> Et quoniã a l, h z ſunt parallelę, ք fabricationẽ:</s>
            <s xml:id="echoid-s10006" xml:space="preserve"> erit
              <lb/>
            g d perpẽdicularis ipſi a l per 29 p 1.</s>
            <s xml:id="echoid-s10007" xml:space="preserve">] Palàm ex prędictis,
              <lb/>
            quoniã n f eſt æquidiſtãs g t, & a l ęquidiſtãs g h:</s>
            <s xml:id="echoid-s10008" xml:space="preserve"> igitur [ք
              <lb/>
            15 p 11] ſuperficies, in qua ſunt n f, al, eſt ęquidiſtãs ſuper-
              <lb/>
            ficiei g t h:</s>
            <s xml:id="echoid-s10009" xml:space="preserve"> ſed linea e g æquidiſtat b m [ք fabricationẽ]
              <lb/>
            quare ſunt in eadẽ ſuperficie [ք 35 d 1] q̃ ſuperficies ſecat
              <lb/>
            preędictas æquidiſtãtes:</s>
            <s xml:id="echoid-s10010" xml:space="preserve"> unã ſuper lineã e g:</s>
            <s xml:id="echoid-s10011" xml:space="preserve"> aliã ſuper li-
              <lb/>
            neã fl.</s>
            <s xml:id="echoid-s10012" xml:space="preserve"> Quare [ք 16 p 11] fl eſt æquidiſtãs e g:</s>
            <s xml:id="echoid-s10013" xml:space="preserve"> ſed a n æqui
              <lb/>
            diſtat eidẽ.</s>
            <s xml:id="echoid-s10014" xml:space="preserve"> Igitur [ք 30 p 1] fl eſt æquidiſtãs an.</s>
            <s xml:id="echoid-s10015" xml:space="preserve"> Verũ ſu
              <lb/>
            perficies cõtingẽs ſpeculũ in pũcto g, ſecat ſuperficies e-
              <lb/>
            aſdẽ æquidiſtãtes:</s>
            <s xml:id="echoid-s10016" xml:space="preserve"> unã in linea e g:</s>
            <s xml:id="echoid-s10017" xml:space="preserve"> aliã in linea o d.</s>
            <s xml:id="echoid-s10018" xml:space="preserve"> Igitur
              <lb/>
            [ք 16 p 11] o d eſt æquidiſtãs e g.</s>
            <s xml:id="echoid-s10019" xml:space="preserve"> Igitur [ք 30 p 1] eſt æ ꝗ-
              <lb/>
            diſtãs a n & l f.</s>
            <s xml:id="echoid-s10020" xml:space="preserve"> Et à pũcto f ducatur linea æ quidiſtãs l a,
              <lb/>
            ſecãs d o in k, & a n in i:</s>
            <s xml:id="echoid-s10021" xml:space="preserve"> ergo f k æqualis l d, & k i æqualis
              <lb/>
            d a.</s>
            <s xml:id="echoid-s10022" xml:space="preserve"> [ք 34 p 1.</s>
            <s xml:id="echoid-s10023" xml:space="preserve">] Quare erit ꝓ portio a d ad d l, ſicut n o ad
              <lb/>
            o f.</s>
            <s xml:id="echoid-s10024" xml:space="preserve"> [nã ք 7 p 5 eſt, ut a d ad d l, ſic i k ad k f:</s>
            <s xml:id="echoid-s10025" xml:space="preserve"> ſed ք 2 p 6, ut
              <lb/>
            i k ad k f, ſic n o ad o f:</s>
            <s xml:id="echoid-s10026" xml:space="preserve"> ergo ք 11 p 5, ut a d ad d l, ſic n o ad o
              <lb/>
            f.</s>
            <s xml:id="echoid-s10027" xml:space="preserve">] Palã etiã, quòd angulus b g z æqualis eſt angulo z g a:</s>
            <s xml:id="echoid-s10028" xml:space="preserve"> [recta enim linea g z bifariã ſecat angulũ a
              <lb/>
            g b, ut patuit] & etiã angulo g l a:</s>
            <s xml:id="echoid-s10029" xml:space="preserve"> [interiori & oppoſito per 29 p 1] & etiã angulo g a l:</s>
            <s xml:id="echoid-s10030" xml:space="preserve"> [alterno ք 29
              <lb/>
            p 1.</s>
            <s xml:id="echoid-s10031" xml:space="preserve">] Quare [per 1 ax.</s>
            <s xml:id="echoid-s10032" xml:space="preserve">] g a l, g l a ſunt æquales:</s>
            <s xml:id="echoid-s10033" xml:space="preserve"> & [ք 6 p 1] g a, g l æquales:</s>
            <s xml:id="echoid-s10034" xml:space="preserve"> & g d քpẽdicularis ſuper
              <lb/>
            al:</s>
            <s xml:id="echoid-s10035" xml:space="preserve"> [per cõcluſionẽ] erit [per 26 p 1] a d æqualis d l.</s>
            <s xml:id="echoid-s10036" xml:space="preserve"> Erit igitur n o ęqualis o f:</s>
            <s xml:id="echoid-s10037" xml:space="preserve"> [demõſtratũ enim eſt,
              <lb/>
            ut a d ad d l, ſic n o ad o f:</s>
            <s xml:id="echoid-s10038" xml:space="preserve"> & alternè, ut a d ad n o, ſic d l ad o f:</s>
            <s xml:id="echoid-s10039" xml:space="preserve"> ſed a d æquatur ipſi d l:</s>
            <s xml:id="echoid-s10040" xml:space="preserve"> ergo ք 14 p 5 n o
              <lb/>
            æquabitur ipſi o f] & g o perpẽdicularis ſuper n f:</s>
            <s xml:id="echoid-s10041" xml:space="preserve"> [parallelæ enim ſunt n f, g t ք fabricationẽ, & g o
              <lb/>
            perpẽdicularis eſt ipſi gt per 18 p 3:</s>
            <s xml:id="echoid-s10042" xml:space="preserve"> ergo per 29 p 1 g o eſt perpendicularis ipſi n f:</s>
            <s xml:id="echoid-s10043" xml:space="preserve"> ideoq́;</s>
            <s xml:id="echoid-s10044" xml:space="preserve"> angulus ad
              <lb/>
            o uterq;</s>
            <s xml:id="echoid-s10045" xml:space="preserve"> rectus eſt] erit [per 4 p 1] angulus o f g ęqualis angulo o n g.</s>
            <s xml:id="echoid-s10046" xml:space="preserve"> Erit igitur angulus n g q ęqua
              <lb/>
            lis angulo m g q.</s>
            <s xml:id="echoid-s10047" xml:space="preserve"> [Nã cũ t q, f n ductę ſint parallelę:</s>
            <s xml:id="echoid-s10048" xml:space="preserve"> æquabitur ք 29 p 1 angulus m g q angulo n f g:</s>
            <s xml:id="echoid-s10049" xml:space="preserve"> ք
              <lb/>
            æqualis cõcluſus eſt ipſi f n g:</s>
            <s xml:id="echoid-s10050" xml:space="preserve"> æquali angulo n g q alterno per 29 p 1.</s>
            <s xml:id="echoid-s10051" xml:space="preserve"> Quare anguli m g q, n g q inter
              <lb/>
            ſe ęquãtur.</s>
            <s xml:id="echoid-s10052" xml:space="preserve">] Igitur [per 12 n 4] à puncto circuli p g, quod eſt g, poteſt punctum m reflecti ad n, nõ
              <lb/>
            impediente pyramide.</s>
            <s xml:id="echoid-s10053" xml:space="preserve"> [Hęc concluſio uidetur repugnare 41 n 4 & 50 n, quibus demonſtratum eſt
              <lb/>
            communem ſectionem ſuperficierum reflexionis & ſpeculi conici cõuexi non eſfe circulum.</s>
            <s xml:id="echoid-s10054" xml:space="preserve"> Qua-
              <lb/>
            re punctum g circuli p g, à quo hic reflexio fieri concluditur, intelligendum eſt punctum circuli,
              <lb/>
            qui eſt communis ſectio ſphæræuel cylindri, quos mens intra conum fingit ac concipit.</s>
            <s xml:id="echoid-s10055" xml:space="preserve">]</s>
          </p>
        </div>
        <div xml:id="echoid-div367" type="section" level="0" n="0">
          <head xml:id="echoid-head356" xml:space="preserve" style="it">53. Si communis ſectio ſuperficierum, reflexionis, & ſpeculi conici cõuexifuerit latus conicũ:
            <lb/>
          ab uno puncto unum uiſibilis punctum ad unum uiſum reflectetur. 33 p 7.</head>
          <p>
            <s xml:id="echoid-s10056" xml:space="preserve">DIco igitur, quòd punctũ b à ſolo g reflectitur ad a.</s>
            <s xml:id="echoid-s10057" xml:space="preserve"> Si enim dicatur, quòd ab alio pũcto poteſt
              <lb/>
            reflecti:</s>
            <s xml:id="echoid-s10058" xml:space="preserve"> illud aut erit in linea lõgitudinis:</s>
            <s xml:id="echoid-s10059" xml:space="preserve"> quę eſt e g:</s>
            <s xml:id="echoid-s10060" xml:space="preserve"> aut nõ.</s>
            <s xml:id="echoid-s10061" xml:space="preserve"> Sit in ea:</s>
            <s xml:id="echoid-s10062" xml:space="preserve"> & ſit x:</s>
            <s xml:id="echoid-s10063" xml:space="preserve"> & ab eo ducatur
              <lb/>
            perpẽdicularis ſuper ſuperficiẽ, cõtingẽtẽ ſpeculũ in pũcto illo:</s>
            <s xml:id="echoid-s10064" xml:space="preserve"> [per 12 p 11] q̃ quidẽ perpẽdi-
              <lb/>
            cularis, erit [ք 6 p 11] ęquidiſtãs z g:</s>
            <s xml:id="echoid-s10065" xml:space="preserve"> & ita [per 30 p 1] æquidiſtãs a l.</s>
            <s xml:id="echoid-s10066" xml:space="preserve"> Igitur a l eſt in ſuperficie reflexio-
              <lb/>
            nis huius perpẽdicularis:</s>
            <s xml:id="echoid-s10067" xml:space="preserve"> [per 35 d 1] & eſt ſimiliter in ſuperficie reflexionis perpẽdicularis z g:</s>
            <s xml:id="echoid-s10068" xml:space="preserve"> [ք
              <lb/>
            35 d 1:</s>
            <s xml:id="echoid-s10069" xml:space="preserve"> parallela enim ducta eſt a l ipſi z g] igitur illæ duæ ſuperficies reflexiõis ſecãt ſe ſuper lineam
              <lb/>
            </s>
          </p>
        </div>
      </text>
    </echo>