To the Fellows of the Royal Society, London. The fabric of the world examined / [Thomas Job].

  • Job, Thomas, 1825-1898.
Date:
[1847]
Catalogue details

Licence: Public Domain Mark

Credit: To the Fellows of the Royal Society, London. The fabric of the world examined / [Thomas Job]. Source: Wellcome Collection.

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    once on its own axis, Mercury must have been only 3 hours 3 minutes 4 seeonds in describing one day, and Venus’s day would be only 12 hours 35 minutes 4 se¬ conds long, also that of Mars would be 55 hours 55 minutes, of Jupiter, 650 hours 16 minutes, of Saturn, 2188 hours 8 minutes nearly, of Herschel, 8827 hours 58 minutes. On observing: the vast differences that are between these results, and the times of their diurnal rotations, 'which are found by observations, I thought of banish¬ ing my hypothesis as incongruent with reason and in¬ consistent with truthbut it is further evident by a •certain well known reason that the motion of the same planet on its axis is much swifter when in its aphelion than in its perihelion, and consequently, the earth turns on its own axis several times more when on the north side of the equinoctial than when on the south side of it. Now, if the aphelion of the earth’s orbit were to be extended so far outward as the orbit of Ju- ]utor, the day when there must be greatly shortened; cm the other hand, if its perihelion were to be con¬ tracted to fthe orbit of Mercury, the day when there must have beeri greatly prolonged. And as this in¬ creasing of the planets’ motion on their axes is occasion¬ ed by the slowness of their motion in their orbits, it must be .inversely as their several distances from the sun, but it has been proved above that by the action of the sun’s rays their motion on their axes must increase in the direct ratio of their several distances from that centre of motion-; therefore, by both of these reasons, the time of the diurnal rotation of each of the planets must be exactly the same, notwithstanding their