very nearly, by the analogy of the lines PS, and MN.
Cor. 18. By the ſame laws by which the body P revolves about the body T, let us ſuppoſe many fluid bodies to move round T at equal diſtances from it; and to be ſo numerous that they may all become contiguous to each other, ſo as to form a fluid annulus or ring, of a round figure and concentrical to the body T; and the ſeveral parts of this annulus, performing their motions by the ſame law as the body P, will draw nearer to the body T and move ſwifter in the conjunction and oppoſition of themſelves and the body S, than in the quadratures. And the nodes of this annulus, or its interſections with the plane of the orbit of the body S, or T, will reſt at the ſyzygies; but out of the ſyzygies they will be carried backward, or in antecedentia; with the greateſt ſwiftneſs in the quadratures, and more ſlowly in other places. The inclination of this annulus alſo will vary, and its axis will oſcillate each revolution, and when the revolution is compleated will return to its former ſituation, except only that it will be carried round a little by the præceſſion of the nodes.
Cor. 19. Suppoſe now the ſphærical body T; conſiſting of ſome matter not fluid, to be enlarged, and to extend it ſelf on every ſide as far as that annulus, and that a channel were cut all round it; circumference containing water; and that this ſphere revolves uniformly about its own axis in the ſame periodical time. This water being accelerated and retarded by turns (as in the laſt corollary) will be ſwifter at the ſyzyſigies, and ſlower at the quadratures than the ſurface of the globe, and ſo will
