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DETERMINATION

OF THE

PRECESSION OF THE EQUINOX,And the different Motions of the Earth’s Axis,Arising from the Attraction of the Sun and Moon.

j^OflOSPSHE Precession of the Equinox, whereby the six’d^ T ^ stars appear to have changed their places by more'iL&'&jt ^ an a Miole sign, since the time of the most ancientAsronomers, is physically accounted for, from the at-traction of the sun and moon on the protuberant matter aboutthe earth’s equator; whereby the position of the said equatorwith relpect to the plane of the ecliptic, is subjected to a per-petual variation. Were the earth to be perfectly spherical andof an uniform density, no change in the position of the terre-strial equator could be produced, from the attraction of any re-mote body; because the force of each particle of matter in theearth, to turn the whole earth about its center, in consequenceof such attraction, would then be exactly counterbalanced byan equal, and contrary force. But as the earth, by reason ofthe centrifugal force of the parts thereof, arising from the di-urnal rotation, must, to preserve an equilibrium, put on an ob-late figure, and rise higher about the equatoreal parts than atthe poles, the action of the fun on the said equatoreal parts willhave an effect to make the plane of the terrestrial equator tocoincide with that of the ecliptic : which would actually be

B brought