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130 Circumference of the Earth is one hundred twenty three Millions, two hundred forty nine thouand ix hundred Feet. This, among other Things, is neceary to prove the Sytem of Attraction.

intant we know the Earth's Circumference, and the Ditance of the Moon, we know that of the Moon's Orbit, and the Diameter of this Orbit. The Moon performs its Revolution in that Orbit in twenty even Days, even Hours, forty three Minutes. 'Tis demontrated, that the Moon in its mean Motion, makes an hundred and fourcore and even thoufand, nine hundred and ixty Feet (of Paris) in a Minute. 'Tis likewie demontrated, by a known Theorem, that the central Force which hould make a Body fall from the height of the Moon, would make its Velocity no more than fifteen Paris Feet in a Minute of Time. Now, if the Law by which Bodies gravitate, and attract one another in an invere Ratio of the Squares of the Ditances be true; if the ame Power