Cardano, Girolamo, De subtilitate, 1663

Page concordance

< >
Scan Original
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
< >
page |< < of 403 > >|
    <archimedes>
      <text>
        <body>
          <chap>
            <p type="main">
              <s id="s.001685">
                <pb pagenum="394" xlink:href="016/01/043.jpg"/>
              per ſe, quòd validiſſimo ictu excutietur
                <lb/>
              verſus D, quia ſimul impetu iacientis, &
                <lb/>
              natura feretur in D. </s>
              <s id="s.001686">Par autem erat, quòd
                <lb/>
              debiliſſimus ictus eſſet illi contrarius, id
                <lb/>
              eſt, verſus C, validiſſimus autem ſuperio­
                <lb/>
              rum verſus D, quorum neutrum experi­
                <lb/>
              mento conſtat: ſed validiſſimus eſt ſupe­
                <lb/>
              riorum FE, mediocris FC, & debiliſſi­
                <lb/>
              mus FA. </s>
              <s id="s.001687">Cur ita? </s>
              <s id="s.001688">Sanè quoniam aër rectà
                <lb/>
              magis, quàm ad latera fertur, igitur debi­
                <lb/>
              liſſimus eſt ictus ex F in A. </s>
              <s id="s.001689">Debuerat iuxta
                <lb/>
              hanc rationem validiſſimus eſſe ex F in C,
                <lb/>
              ſed quia tota grauitas obſtat ponderis, ideò
                <lb/>
              vbi aër maximè mouetur, & pondus mi­
                <lb/>
              nus grauitatis habet, hoc autem eſt in linea
                <lb/>
              FE, ibi validiſſimè torquetur pila. </s>
              <s id="s.001690">Reli­
                <lb/>
              quum eſt igitur vt mediocriter ex F in C
                <lb/>
              feratur, id eſt, rectà in ſublime. </s>
              <s id="s.001691">Ne tamen
                <lb/>
              erres in ſagittis, quæ ob longitudinem &
                <lb/>
              alas velociùs quandoque feruntur ex F in
                <lb/>
              A, quàm in C, nunquam autem magis,
                <lb/>
              quàm in E: ob id qui muros quatiunt, ma­
                <lb/>
              chinas ad ſemiorthon, id eſt, ad libellam
                <lb/>
              FE collocant: nam tertia fermè parte ictus
                <lb/>
              augetur. </s>
              <s id="s.001692">Cùm verò pila ad ſupremum re­
                <lb/>
              ctà peruenerit, non per circulum, nec
                <lb/>
              rectà ſurſum illicò deſcendit, ſed media
                <lb/>
                <arrow.to.target n="marg175"/>
                <lb/>
              quaſi linea, quæ parabolæ fermè imita­
                <lb/>
              tur circum ambientem lineam, vt BC eſt,
                <lb/>
              demùm ex C in D motu grauis rectà ad vn­
                <lb/>
              guem.
                <lb/>
                <figure id="id.016.01.043.1.jpg" xlink:href="016/01/043/1.jpg" number="26"/>
                <lb/>
                <arrow.to.target n="marg176"/>
              </s>
            </p>
            <p type="margin">
              <s id="s.001693">
                <margin.target id="marg174"/>
              Ratio motus
                <lb/>
              grauium
                <expan abbr="">cum</expan>
                <lb/>
              violenter
                <lb/>
              mouentur.</s>
            </p>
            <p type="margin">
              <s id="s.001694">
                <margin.target id="marg175"/>
              Modus quo
                <lb/>
              grauia poſt
                <lb/>
              ictum deſ­
                <lb/>
              cendunt.</s>
            </p>
            <p type="margin">
              <s id="s.001695">
                <margin.target id="marg176"/>
              Cur vix vl­
                <lb/>
              lus feriatur
                <lb/>
              à plumbeis
                <lb/>
              pilulis, quæ
                <lb/>
              maximo nu­
                <lb/>
              mero in al­
                <lb/>
              tum mit­
                <lb/>
              tuntur.</s>
            </p>
            <p type="main">
              <s id="s.001696">Quæ igitur proiiciuntur, tribus ex moti­
                <lb/>
              bus conſtant, primo violento, vltimo ex­
                <lb/>
              quiſitè naturali, & medio ex vtroque mi­
                <lb/>
              ſto: propter tam multiplicem motus ratio­
                <lb/>
              nem metiri ad vnguem talia planè eſt im­
                <lb/>
              poſſibile, coniectura tamen aſſequi licet.
                <lb/>
              </s>
              <s id="s.001697">Debiliſſimi planè motus ex B in C: vnde
                <lb/>
              plumbeæ pilæ calore diſſipatæ, ob hoc etiam
                <lb/>
              minùs lædunt, vt vix vnum aut alterum,
                <lb/>
              ob ictus in ſublime deſtinatos, quum tamen
                <lb/>
              frequenter aut auium cauſa, aut exoneran­
                <lb/>
              dæ machinæ, emitti ſoleant pilæ ſemiuncia
                <arrow.to.target n="marg177"/>
                <lb/>
              grauiores, vulneratos aut grauiter percuſſos
                <lb/>
              videas inter tot millia. </s>
              <s id="s.001698">Sed quum per æqui­
                <lb/>
              diſtantem finitori lineam tam difficulter
                <lb/>
              grauia moueantur, cur eſt quòd ſuſpenſa
                <lb/>
              facilè adeò impelluntur, vt annulus filo ſuſ­
                <lb/>
              penſus ſpontè videatur moueri, atque ob id
                <lb/>
              etiam præcantationis præſe fert imaginem?
                <lb/>
              </s>
              <s id="s.001699">Cauſa eſt, quòd tota vis integra impellen­
                <lb/>
              ti relinquitur: qui verò proiicit, duo facit,
                <lb/>
              ſuſtinet & impellit: at appenſo pondere,
                <lb/>
              quum ab alio iam ſuſtineatur: quicquid
                <lb/>
              virium eſt ad impulſum integrum manet.
                <lb/>
              </s>
              <s id="s.001700">At vero quum impellitur, tanta fermè vi
                <lb/>
              redit ad medium, quanta ab illo, depul­
                <lb/>
              ſum eſt: igitur quum ea vi iam depulſum
                <lb/>
              fit à medio, gratia exempli per cubiti ſpa­
                <lb/>
              tium, tantundem diſcedere in contrariam
                <lb/>
              partem neceſſarium erit, atque ita conti­
                <lb/>
              nuo ac alternato reditu tardiſſimè con­
                <lb/>
              quieſcere. </s>
              <s id="s.001701">Cùm igitur in annulo motus hic
                <lb/>
              vel occulta ſpirituum motione paululùm
                <lb/>
              iuuatur, adeò ſpontè augetur, vt verbis
                <lb/>
              vim fuiſſe credas. </s>
              <s id="s.001702">Quamobrem cùm pau­
                <lb/>
              lò concitatior eſt annuli motus, ipſo iam
                <lb/>
              ( vt dixi ) ſeipſum mouente, videtur annu­
                <lb/>
              lo dæmon ineſſe, qui annulum moueat. </s>
              <s id="s.001703">Eſt
                <lb/>
              autem motus hic etiam in filo longiore fa­
                <lb/>
              cilior, euidenti demonſtratione. </s>
              <s id="s.001704">Sit enim
                <lb/>
              annulus in F, & moueatur per BC, ſuſ­
                <lb/>
              penſus in A, & rurſus ſuſpenſus in A po­
                <lb/>
              natur in G, & moueatur per DHE, quæ ſit
                <lb/>
              æqualis BFC, & L centrum terræ: con­
                <lb/>
              ſtat igitur, quod dum eſt in F, mouebitur
                <lb/>
              contra naturalem motum per FG: & dum
                <lb/>
              eſt in H, per HK, ſed HK eſt breuior FG,
                <lb/>
              vt in primo de Circulis demonſtrauimus.
                <lb/>
              </s>
              <s id="s.001705">Igitur cùm potentia mouens eadem ſit, &
                <lb/>
              quod mouetur idem, & maius tranſeat
                <lb/>
              ſpatium in F quàm in H, à centro, ſeu ma­
                <lb/>
              gis aſcendat, tranſibit illud in longiori tem­
                <lb/>
              pore: igitur ſi in æquali tempore debent
                <lb/>
              moueri, minore impetu indiget H, quàm F,
                <lb/>
              & ideò quantò altiùs ſuſpenditur, eò faci­
                <lb/>
                <figure id="id.016.01.043.2.jpg" xlink:href="016/01/043/2.jpg" number="27"/>
                <lb/>
              liùs mouetur mobile, & minori labore.
                <lb/>
              </s>
              <s id="s.001706">Cùm igitur filum longum fuerit, initium
                <lb/>
              motus ducet, vel ab incauto manuum mo­
                <lb/>
              tu, vel ab aëre, vel à ſpiritibus ipſis, quo­
                <lb/>
              rum vis etiam per filum deſcendit. </s>
              <s id="s.001707">Ita adeò
                <lb/>
              facili motu illius, & tot cauſis mouenti­
                <lb/>
              bus, nil mirùm immotis digitis, & fili ini­
                <lb/>
              tio annulum moueri, quo moto vix ceſſa­
                <lb/>
              tionis, cùm graue ( vt dixi ) appenſum tam
                <lb/>
              pertinaciter ſeipſum moueat, initium pote­
                <lb/>
              rit inuenire: atque hoc modo præcantatio­
                <lb/>
              ne moueri videtur. </s>
            </p>
            <p type="margin">
              <s id="s.001708">
                <margin.target id="marg177"/>
              De motu
                <lb/>
              annuli.</s>
            </p>
            <p type="main">
              <s id="s.001709">Sed poſtquam hæc clara ſunt: dubitabit
                <lb/>
              aliquis, cur tenuia corpora non ſolum mo­
                <lb/>
              tum velocem admittunt, quòd rationi con­
                <lb/>
              ſonum eſt, ſed etiam faciunt, quod diſſonum
                <lb/>
              eſt? </s>
              <s id="s.001710">Nam impulſus aquæ minùs violentus
                <lb/>
              eſt, cum alicui rei intruditur, quàm aëris, &
                <lb/>
              aëris, quàm ignis, Indicio fuit inſtrumen­
                <lb/>
              tum, quod ( vt audio ) nam non vidi, Ger­
                <lb/>
              manus attulit, vlnas longum 20. ex cupreſ­
                <lb/>
              ſo, cuius foramen adeò anguſtum erat, vt
                <lb/>
                <arrow.to.target n="marg178"/>
                <lb/>
              cicerem etiamſi rotundus fuiſſet, non eſſet
                <lb/>
              admiſſurum. </s>
              <s id="s.001711">Craſſitudo vlna minor. </s>
              <s id="s.001712">Impel-</s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>