have been in a great measure discovered, and most of them made out by Mathematical Demonstration in this our Century , by the accurate diligence of Galilæus , Torricellius , Hugenius , and others, and now lately by our worthy Countryman, Mr. Isaac Newton , which Properties it may be very material here to enumerate, that they may serve for a Foundation to all those that shall be willing to spend their Thoughts in search of the true Cause of this Descent of Bodies .
The first Property is, That by this Principle of Gravitation, all Bodies do descend towards a Point, which either is, or else is very near to the Center of Magnitude of the Earth and Sea, about which the Sea forms it self exactly into a Spherical Surface, and the Prominences of the Land, considering the Bulk of the whole, differ but insensibly therefrom.
Secondly, That this Point or Center of Gravitation, is fix'd within the Earth, or at least has been so, ever since we have any Authentick History: For a Consequence of its Change, though never so little, would be the over-flowing of the low Lands on that side of the Globe towards which it approached, and the leaving new Islands bare on the opposite side, from which it receded; but for this Two Thousand Years it appears, that the low Islands of the Mediterranean Sea (near to which the ancientest Writers liv'd) have continued much at the same height above the Water, as they now are found; and no Inundations or Recesses of the Sea arguing any such Change, are recorded in History; excepting the Universal Deluge, which can no better way be
accounted for, than by supposing this Center of Gravitation removed for a time, towards the middle of the then inhabited Parts of the World; and a change of its Place, but the Two Thousandth Part of the Radius of this Globe, were sufficient to bury the Tops of the highest Hills under Water.