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132 thee Laws, all thee Relations are indeed oberv'd by the Planets with the utmot Exactnes; therefore the Power of Attraction caues all the Planets to gravitate towards the Sun, in like Manner as the Moon gravitates towards our Globe.

, as in all Bodies, Re-action is equal to Action, 'tis certain that the Earth gravitates alo towards the Moon; and that the Sun gravitates towards both: That every one of the Satellites of Saturn gravitates towards the other four, and the other four towards it: All five towards Saturn, and Saturn towards all. That 'tis the ame with regard to Jupiter; and that all thee Globes are attracted by the Sun, which is reciprocally attracted by them.

Power of Gravitation acts proportinably to the Quantity of Matter in Bodies, a Truth which Sir Iaac has demontrated by Experiments. This new Dicovery has been of ue to how, that the Sun (the Center of the planetary Sytem) attracts them all in a direct Ratio of their Quantity of Matter combin'd with their nearnes. From hence Rh