Caverni, Raffaello, Storia del metodo sperimentale in Italia, 1891-1900

Table of figures

< >
[Figure 151]
Page: 992
[Figure 152]
Page: 997
[Figure 153]
Page: 1000
[Figure 154]
Page: 1000
[Figure 155]
Page: 1001
[Figure 156]
Page: 1001
[Figure 157]
Page: 1001
[Figure 158]
Page: 1009
[Figure 159]
Page: 1021
[Figure 160]
Page: 1023
[Figure 161]
Page: 1024
[Figure 162]
Page: 1025
[Figure 163]
Page: 1026
[Figure 164]
Page: 1029
[Figure 165]
Page: 1031
[Figure 166]
Page: 1063
[Figure 167]
Page: 1064
[Figure 168]
Page: 1065
[Figure 169]
Page: 1077
[Figure 170]
Page: 1083
[Figure 171]
Page: 1089
[Figure 172]
Page: 1098
[Figure 173]
Page: 1103
[Figure 174]
Page: 1129
[Figure 175]
Page: 1172
[Figure 176]
Page: 1197
[Figure 177]
Page: 1227
[Figure 178]
Page: 1233
[Figure 179]
Page: 1237
[Figure 180]
Page: 1239
< >
page |< < of 3504 > >|
    <archimedes>
      <text>
        <body>
          <chap>
            <p type="main">
              <s>
                <pb xlink:href="020/01/1026.jpg" pagenum="469"/>
              hyperbolicae, ac certo et immutabili interstitio circa medium a medio cor­
                <lb/>
              pore remoto, mobilia tamen una cum corpore intermedio circa unicam axem
                <lb/>
              certa periodo ” (pag. </s>
              <s>3, 4). </s>
            </p>
            <p type="main">
              <s>Le figure ombreggiate, di che fa cenno l'Autore, sono in numero di
                <lb/>
              sei impresse tutte insieme e per ordine numerate in una Tavola a rappre­
                <lb/>
              sentar la successione delle principali fasi saturnie, che si distinguono cia­
                <lb/>
              scuna col nome proprio di
                <emph type="italics"/>
              Saturnus elliptico-ansatus plenus, S. ellipticus
                <lb/>
              ansatus diminutus, S. sphaerico-ansatus, S. sphaerico-cuspidatus, S. tri­
                <lb/>
              corporeus, S. monosfaericus.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="main">
              <s>Prototipa è la prima figura, la quale nell'intenzion dell'Hevelio rap­
                <lb/>
              presenta Saturno composto di un globo ellittico nel mezzo, con un'ansa
                <lb/>
              attaccata di qua e di là dalle due parti. </s>
              <s>Supponeva l'Autore che tutto il
                <lb/>
              sistema facesse in 30 anni una rotazione intiera intorno al suo asse minore
                <lb/>
              perpendicolarmente eretto e stabile sul piano dell'orbita planetaria, e così
                <lb/>
              sperava che sarebbero regolarmente apparite le varietà delle fasi secondo
                <lb/>
              l'ordine divisato. </s>
              <s>Ma presto si videro i fatti non approvar l'ipotesi, impe­
                <lb/>
              rocchè, secondo la predizion dell'Hevelio, la fase rotonda del 1656 doveva
                <lb/>
              mantenersi infino al Settembre dell'anno appresso, e nonostante infin dal
                <lb/>
              dì 13 d'Ottobre di quell'anno 1656 si vide Saturno riapparire coll'anse,
                <lb/>
              mantenendosi in quella medesima apparenza anche dopo. </s>
            </p>
            <p type="main">
              <s>Fallace il Sistema heveliano si dimostrava altresì dal riscontro delle fasi
                <lb/>
              antecedentemente osservate, fra le quali insigni nella storia del Pianeta erano
                <lb/>
              quelle descritte, nella III Lettera velseriana, da Galileo. </s>
              <s>Nel solstizio del­
                <lb/>
              l'anno 1612, quando Saturno era nei 18° 22′ de'Pesci, Galileo l'osservò tri­
                <lb/>
              corporeo, mentre sarebbe dovuto per le Tavole dell'Hevelio comparire ro­
                <lb/>
              tondo; e similmente, nel Dicembre di quell'anno 1612, essendo Saturno in
                <lb/>
              11° 27′ de'Pesci, Galileo l'osservò rotondo, mentre si doveva per l'Hevelio aspettare trisferico. </s>
            </p>
            <p type="main">
              <s>Ma se in ogni modo per prototipo delle altre fasi stabilivasi quella de­
                <lb/>
              signata col nome di
                <emph type="italics"/>
              ellittico ansata piena,
                <emph.end type="italics"/>
              non si vedeva come potessero
                <lb/>
              da questa sola derivarsi tutte le varie apparenze del Pianeta. </s>
              <s>Sia infatti nella
                <lb/>
              figura 96 ABCD il globo ellissoideo di Saturno, a cui sieno attaccate le anse
                <lb/>
              EF, GH e si volga tutto il sistema attorno all'asse BD. </s>
              <s>Non v'ha dubbio
                <lb/>
                <figure id="id.020.01.1026.1.jpg" xlink:href="020/01/1026/1.jpg" number="163"/>
              </s>
            </p>
            <p type="caption">
              <s>Figura 96.
                <lb/>
              che da chiunque stesse di faccia a riguar­
                <lb/>
              dare le apparenti mutazioni di figura pre­
                <lb/>
              sentate da questo moto, si vedrebbero le
                <lb/>
              anse andar via via sempre più ad acco­
                <lb/>
              starsi al globo centrale, e così potrebbe
                <lb/>
              Saturno in questa ipotesi mostrarsi sotto
                <lb/>
              l'aspetto di ellittico ansato diminuito, e di
                <lb/>
              sferico ansato. </s>
              <s>Seguitando poi tutto il si­
                <lb/>
              stema a volgersi regolarmente attorno, giunto a presentar l'asse maggiore
                <lb/>
              in direzione del raggio visuale, potrebbe altresi pigliar la forma monosferica,
                <lb/>
              ma dovendo secondo il supposto dell'Hevelio, le altezze EF, GH mantenersi </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>
Impressum