Several Observations of the Eclipse of Jupiter by the Moon on March the 31th. 1686. St.Vet. Where-Of Some Account Has Already been Given in Transaction No. 181

nem, qui vicem Prefecti Annonae obiret, & in omnibus istis inferiorum Decurionum Collegiis primum teneret locum, id manifeste ex hac patet Inscriptione, ubi minores Decuriones Bovillani honorem faciunt Equiti Romano & Palatino, qui Decurio seu Curialis & Fretriacus in omnibus esset locis & urbibus, a quibus & per quas Annona Aegyptiaca Romam devehbatur. Decuriones vero promotos fuisse ad honorem Sacerdotii, ita ut simul Flamines, Luperci, Epulones Jovis, & Parasiti fuerent Apollinis; & hoc quoq; multos constat exemplis. Omne vero dubium tollit, quod in hac Inscriptione eques ille Romanus vocetur Antinoiton & Eunostidon Decurio. Antinoi enim urbs praecipua tum temporis Aegypti superioris erat Civitas, unde per multas fossas frumentum deferebatur ad Mareotin lacum, qui ad Eunosti portum exit in Mare. Ab hoc portu dicti Eunostida curatores frumenti Aegyptiaci; unde demum confectus deus Eunostus rei frumentaria Inspector, qui huic praesideret portui. Several Observations of the Eclipse of Jupiter by the Moon on March the 31st. 1686. St.Vet. whereof some account has already been given in Transaction No. 181. The most accurate Observation of this Eclipse we have received, is that of Mr. Cassini, made in the Royal Observatory at Paris, published in the Journal des Scavans of the 10th of June last, the substance whereof is as follows. April 10th. St. N. Vesperi Mr. Cassini, assisted by other Astronomers, attended upon this Occultation with Telescopes of 21 and 70 foot, while one was deputed to take the Altitudes of 4 to verify the time. At 9h. 31m. 6sec. 4 was in a perpendicular falling on the Limb of the over against the Northern Part of the spot Grimaldi (Mareotis) near to Riccioli (stag. Miris) and was distant from the Limb about four times as much as the said spot. 9h. 4m. 21sec. \( \gamma \) touched the circumference of \( \sigma \), which undulated by reason of the Vapours near the Horizon. 9h. 41. 20. he quite disappeared in the inequalities of the \( \sigma \)'s Limb, the total Immersion might be some seconds later. So the central immersion was at 9h. 40m. 51sec. \( \gamma \) entered over against that part of Grimaldi next Riccioli. The Vapours of the Horizon hindered the Observation of the Immersions of the Satellites, but not their Emersions, for At 10h. 30m. 2sec. the outermost Satellite which preceded \( \gamma \), appeared over against the middle of the Caspian Spot (pal. Maoris) through which the section of Light and Darkness passed, and made nearly an equilateral Triangle with the Extremities of that spot. At 10h. 40m. 24sec. the first Limb of \( \gamma \) began to come out of the dark side of the \( \sigma \), over against the North part of the Caspian spot, about Cleomedes, (ad montes Ripheos) At 10h. 40m. 56sec. the center of \( \gamma \) did emerge. It was difficult to distinguish the moment when \( \gamma \)'s disk was fully clear, but at 10h. 41m. 36sec. the Eclipse was certainly past. At the Emersion of the Center, the Altitude of \( \gamma \) was 11d. 31m. At 10h. 42m. 49s, the second Satellite, being the nearest of the three that followed the Planet, emerged. At 10h. 45m. 1s. the innermost Satellite, being near its greatest Elongation, emerged. At 10h. 50m. 40s. the third or penextimus Satelles, being likewise near its greatest Elongation, began to appear over against the Northern Edge of the Caspian Spot. At 10h. 45m. the Diameter of the \( \sigma \) was 32m. 27s. and according to the calculus of Mr. Cassini, her parallax was 61min. Together with this Observation is joined that of R. P. Bonfa made at Avignon who observed the central immersion at 9h. 42m. 13s. and the central Emersion at 10h. 45m. 26s. over over against the Southern part of the Caspian Spot. The same P. Bonfa has also observed at Avignon the other Eclipse of the same Planet, April 28th. st. vet Mane. The Immersion of the Center hapned at 3h. 37m. 23s. on the East side of the Spot Xenophanes. The Emerion was at 4h. 28m. 2s. between Seneca and Berosus, according to Riccioli, or ad montes Aianos Hevelii, a little to the Northward of the Palus Maeotis. This occultation could not be observed at Paris by reason of Clouds. Another printed Paper about the Eclipse of March 31st, is since come to hand from Nurenburg, where it was observed part, by Mr. I. Iac Zimmerman, and by Mr. Wurtzelbauer, the substance of whose Observations is as follows. At 10h. 19m. 56s. Mr. Zimmerman observed the first contact of the Limbs of υ and the ι, and at 10h. 20m. 47s. υ was all eclipsed. At 11h. 22m. 51s. υ was wholly clear from the Eclipse. The Immersion was about the 117th, the Emerion at the 321th. Degree of the Limb, in the Chart of Hevelius. At 11h. 31m. 06s. the third Satellite of υ emerged. These times were collected from the Culminations of fixt Stars, and the Vibrations of a Pendulum. The Relation of the other Observer Mr. Wurtzelbauer is to this purpose. At 10h. 20m. 50s. υ applied to the Limb of the ι, over against the loca paludosa Insulae Circinnae. At 11h. 22m. 00s. he appeared about half eclipsed. At 10h. 22m. 30s. he was wholly hid. At 11h. 19m. 40s. υ began to Emerge. At 11h. 21m. 20s. he was quite free from the interposition of the ι. The point of the Emerion was somewhat to the North of the Palus Maeotis. No Spot in the ι was so near the apparent magnitude of υ's disk as the Insula Besbicus Hevelii. At 11h. 40m. 00s. the Altitude of Procyon was 8gr. 37m. whence the Pendulum Clock, which had been set by Altitudes tudes of the o the afternoon preceding, may be examined. The Account we have but now lately received from the famous Mr. Hevelius from Dantzick, of these same Eclipses, is contained in this following Discourse addressed in a Letter from the Observer to the R. Society. Occultatio Jovis Anno 1686, die 10 April. st. n. vesperi, observata Gedani a Joh. Hevelio. Ad hanc Observationem summa alacritate accessi, non obstante invaletudine mea, cum Coelum fere undeque esset serenum, nisi quod circa Horizontem, ubi Luna atq; Jupiter exoriri debebant, vapores quidam atq; nubeculae existent. Inprimis ex eo maximopere fui excitatus, quod hujus generis Observationes, Occultationes nempe Jovis admodum raro contingant, sed adhuc rarius ex voto observentur. Me quod attinet, scias, mi Lector, etiam si huc usque per 56 annos Rebus Coelestibus pro meo modulo operam dederim, atq; nullam Observationem aliquus momenti, (absit gloriola) lubens neglexerim, haud feliciorem fuisse quam quod in hunc usque diem spatium circiter annorum, non nisi tres tales Jovis Eclipses rite deprehendere & annotare potuerim: utpote primam Anno 1646, die 24 Decemb. vesperi, sed tantummodo ejus finem: secundam, Anno 1679, die 5 Junii ante meridiem de die, quo tempore res omnis felicius successit; tertiam hoc Anno currente 1686 die 10 April. vesperi. Quam Observationem, mi Astrophile, prout persagi potuit, a me nunc benevole accipias, rogo. Quae vero obtenta, atq; annotata fuerunt, ex subsequeente Tabella & Observationis Typo patebunt. Omnium primo nonnullas Altitudines Solis, & Arcturi Quadrante singula minuta commonitrante observavi, ad corrigendum Horologium ambulatorium aliquanto tardius incedens. Deinde, exoriente atq; ex nu-