 this Island cannot move beyond the Extent of
the Dominions below; nor can it rise above the Height of four Miles. For which
the Astronomers (who have written large Systems concerning the Stone) assign the
following Reason: That the Magnetick Virtue does not extend beyond the Distance
of four Miles, and that the Mineral which acts upon the Stone in the Bowels of
the Earth, and in the Sea about six Leagues distant from the Shoar, is not
diffused through the whole Globe, but terminated with the Limits of the King's
Dominions: And it was easy from the great Advantage of such a superior
Situation, for a Prince to bring under his Obedience whatever Country lay within
the Attraction of that Magnet.
    When the Stone is put parallel to the Plane of the Horizon, the Island
standeth still; for in that Case, the Extremities of it being at equal Distance
from the Earth, act with equal Force, the one in drawing downwards, the other in
pushing upwards; and consequently no Motion can ensue.
    This Load-stone is under the Care of certain Astronomers, who from Time to
Time give it such Positions as the Monarch directs. They spend the greatest Part
of their Lives in observing the celestial Bodies, which they do by the
Assistance of Glasses, far excelling ours in Goodness. For, although their
largest Telescopes do not exceed three Feet, they magnify much more than those
of a Hundred with us, and shew the Stars with greater Clearness. This Advantage
hath enabled them to extend their Discoveries much farther than our Astronomers
in Europe. They have made a Catalogue of ten Thousand fixed Stars, whereas the
largest of ours do not contain above one third Part of that Number. They have
likewise discovered two lesser Stars, or Satellites, which revolve about Mars;
whereof the innermost is distant from the Center of the primary Planet exactly
three of his Diameters, and the outermost five; the former revolves in the Space
of ten Hours, and the latter in Twenty-one and an Half; so that the Squares of
their periodical Times, are very near in the same Proportion with the Cubes of
their Distance from the Center of Mars; which evidently shews them to be
governed by the same Law of Gravitation, that influences the other heavenly
Bodies.
    They have observed Ninety-three different Comets, and settled their Periods
with great Exactness. If this be true, (and they affirm it with great
Confidence) it is much to be wished that their Observations were made publick;
whereby the Theory of Comets, which at present is very lame and defective, might
be brought to the same
