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 ASTRONOMY. 495In fixing the year of the creation to the 706th year was at the noon of the fourth day of the creation-week, of the Julian period, which was the 4007th year before and that the moon was then 24 hours pad her oppofition the year of Chrift’s birth, we have followed Mr Bed- to the fun. — If Mofes had told us the fame things, we ford in his fcripture chronology, printed A. D. 1730, Ihould have had fufficient data for fixing the tera of the and Mr Kennedy in a work of the fame kind, printed creation: But, as he has been filent on thefe points, we A. D. 1762.—Mr Bedford takes it only for granted that muft cohfider the bed accounts of chronologers as entire the world was created at the time of the autumnal equi- ly hypothetical and uncertain. nox : But Mr Kennedy affirms, that the faid equinox

G h a P. XIX. A Deferiftion of, the. Afronomical Machinery ferving to explain and illufrate the foregoing part of this Treatife. The Orrery, (Plate XLVII. fig. 4.) This machine fhews the motions of the fun. Mercury, Venus, earth, and moon; and occafionally the fuperior planets, Mars, Jupiter, and Saturn, may be put on; Jupiter’s four fatellites are moved round him in their proper times by a fmall winch; and Saturn has his five fateilites, and his ring which keeps its parailelifm round the fun ; and by a lamp put in the fun’s place, the ring {hews all its various phafes already deferibed. In the centre, No. 1. reprefents the fun, fupported by its axis, inclining almoft 8 degrees from the axis of

the ecliptic, and turning round in 25^ days on its axis, of which the north pole inclines toward the 8th degree 6f Pifces in the great ecliptic, (No. 11.), whereon the months and days are engraven over the figns and degrees in which the fun appears,.as-feen-from the earth, on the different days of the year. The neared planet (No. 2.) to the funis Mercury, which goes roundof him 87 days or 87^round diurnal rotations the inearth; but 23hashours, no motion its axis in the machine, becaufe the time of its diurnal motion in the heavens is not known to us. The next planet in order is Venus, (No. 3.), which performs days or17inhours, and turns roundherherannual axis courfe-in in 24 days 224 8 hours, 244- diurnal rotations of the earth. Her axis inclines 75 degrees from the axis of the icliptic, and her north pole inclines towards' t