( 4°4 )

i lnterlhtium dabit mter centrum jovu oc i J nmi, 339; facundi, 5564 Tertii,

ii ; Quarti, Zyt ; quibus sigillatim per 66 divisis, prodeunt Elongationesparentes a centro Jovis in Semidiametris ejusdem, Primi quidem. zM. gq:undi, 8 sd 25/ ; Tertii, I 3^ 2l'; Quarti, 13 sd 30'.

apparuit; Tertiut infra eam, sed & aliquando existimavi in ea! Joviscapta diameter 131, Semidiameter ergo 66. observatis quas subducta Distan-tiis interstitium dabit inter centrum Jovis & Primi, 339 ; Secundi, yy6; Tertii,881 ' " .. .- - ■

apparentesSecundi,

Satcllitmn Motus Medii a Pleni-Mediceis, cum Distantiis eorum ä centro

Jovis, secundum numeros tuos fuere, ut inhac tabellula exarantur. Unde videre est,Primum a summa Elongatione abesse scrupu-los Semidiametri 10' ; Secundum, 26'; Terti-um, 38'; quos propterea si observatis Elonga-tionibus adjiciamus, fient Maxima hinc dedQcendai Digressiones.

s. 0 '

I

8 xy 35

2

2 10 59

z

2 12 2

U

10 27 8 '

sd. '

4 50

7

ix

13

H 1

2X 1

1 s

PrimiSecundiTertii '

sd.

5

8

l?

18

5-

perparum ab iis, quas observationibus noctis Quar-tas deduximus, dissentientes.

His tamen utrisque vicibus Intimus Satelles ad Lxvam, Secundus & Tertiusad dextram, a Jove apparuere; sed Apr. 15. vesp. Tertium a sinistra, in maxi-ma Elongatione appariturum praevidi, cui propterea Phxnomeno invigilareoperae fore pretium duxi, nimirum ut perspicerem, num eadem esset ejusdemSatellifis ad manum utramque a centro Jovis, summa Remotio. Caelum no-cte observationi antedicta sudum erat; sic pro voto observavi circa lm.

Tertii Distantiam 955 ; & Jovis Diam. 13 I. Jovis ergo Semidiameter-5^7,observatae qua subducta Distantiae, fit interstitium inter centrum Jovis & Sa-tellitem, 889 i quod per eandem Semidiametrum divisum visibilem dat Elon-gationem Comitis a Centro Jovis in Semidiametris ipsius 13^ 3 jsi Motus Sa-tellitis. medius erat 3* 14° 9': Locus Jovis verus — i-o° 27. Ergo Planetaa Pleni Mediceo 9 * 3 ° 4 ^ aberat, a summa Elongatione tantum scrupulos3 ; quos si observatae digressioni x 3 sd 3 5' adjiciamus, fiet maxima ad Sini-stram hac vice 13^ 38', parte nimirum tertia Semidiametri minor quam adDextram, bis conspirantibus notis, observavimus: Quod mihi videtur innuere,,esse aliquam Centri Orbitae hujus Planet a a Centro Jovis Excentricitatcm.

2. The Little Circle in the Middle represcnts the Planet Jupiter, , the fouran Instrument Concentrick Circles, the Proper Orbits of his (ourSatellites, düly proportion-frr findig tbe ed to the Breadth of hisBody; the Distances betwixt the parallel Lines inter»t ^ em » being each equal to one of his Semidiameters.fiteijronfhu The 4 divided Circles next without these, are distinguishcd ihto fb manyOxis -, by Mr. parts as therc are days and hours in each Sattellites Revolution ; .the inqer-^i78?^irS2. Mols of them scrving for the Firfl or Innermofi Satellite ; that next it, for the2<i; that next without this for the 3 d ; and theoutermost for the 4^ ; abovewhich'.is asinali divided Arch of iy Degrees*.

By this-to find; the Distanees of the Satellites from ty.Axis to a _proposedTime

1. Find.