SUMMARY:  A Phænomenon solved by modern Philosophy and Astronomy. TheLaputias great Improvements in the latter. The King's Method of suppressing Insurrections.

    I DESIRED Leave of this Prince to see the Curiosities of the Island; which he was graciously pleased to grant, and
ordered my Tutor to attend me. I chiefly wanted to know to what Cause in Art or in Nature, it owed its several Motions;
whereof I will now give a philosophical Account to the Reader.

 The flying or floating Island is exactly circular; its Diameter 7837 Yards, or about four Miles and an Half, and
consequently contains ten Thousand Acres. It is three Hundred Yards thick. The Bottom or under Surface, which
appears to those who view it from below, is one even regular Plate of Adamant, shooting up to the Height of about two
Hundred Yards. Above it lye the several Minerals in their usual Order; and over all is a Coat of rich Mould, ten or
twelve Foot deep. The Declivity of the upper Surface, from the Circumference to the Center, is the natural Cause why all
the Dews and Rains which fall upon the Island, are conveyed in small Rivulets toward the Middle, where they are
emptyed into four large Basons, each of about Half a Mile in Circuit, and two Hundred Yards distant from the Center.
From these Basons the Water is continually exhaled by the Sun in the Day-time, which effectually prevents their
overflowing. Besides, as it is in the Power of the Monarch to raise the Island above the Region of Clouds and Vapors,
he can prevent the falling of Dews and Rains whenever he pleases. For the highest Clouds cannot rise above two Miles,
as Naturalists agree, at least they were never known to do so in that Country.

 At the Center of the Island there is a Chasm about fifty Yards in Diameter, from whence the Astronomers descend into
a large Dome, which is therefore called Flandona Gagnole, or the Astronomer's Cave; situated at the Depth of an
Hundred Yards beneath the upper Surface of the Adamant. In this Cave are Twenty Lamps continually burning, which
from the Reflection of the Adamant cast a strong Light into every Part. The Place is stored with great Variety of
Sextants, Quadrants, Telescopes, Astrolabes, and other Astronomical Instruments. But the greatest Curiosity, upon
which the Fate of the Island depends, is a Loadstone of a prodigious Size, in Shape resembling a Weaver's Shuttle. It is
in Length six Yards, and in the thickest Part at least three Yards over. This Magnet is sustained by a very strong Axle of
Adamant passing through its Middle, upon which it plays, and is poized so exactly that the weakest Hand can turn it. It is
hooped round with a hollow Cylinder of Adamant, four Foot deep, as many thick, and twelve Yards in Diameter, placed
horizontally, and supported by Eight Adamantine Feet, each six Yards high. In the Middle of the Concave Side there is a
Groove Twelve Inches deep, in which the Extremities of the Axle are lodged, and turned round as there is Occasion.

 The Stone cannot be moved from its Place by any Force, because the Hoop and its Feet are one continued Piece with
that Body of Adamant which constitutes the Bottom of the Island.

 By means of this Load-stone, the Island is made to rise and fall, and move from one Place to another. For, with respect
to that Part of the Earth over which the Monarch presides, the Stone is endued at one of its Sides with an attractive
Power, and at the other with a repulsive. Upon placing the Magnet erect with its attracting End towards the Earth, the
Island descends; but when the repelling Extremity points downwards, the Island mounts directly upwards. When the
Position of the Stone is oblique, the Motion of the Island is so too. For in this Magnet the Forces always act in Lines
parallel to its Direction.

 By this oblique Motion the Island is conveyed to different Parts of the Monarch's Dominions. To explain the Manner of
its Progress, let A B represent a Line drawn cross the Dominions of Balnibarbi; let the Line c d represent the
Loadstone, of which let d be the repelling End, and c the attracting End, the Island being over C; let the Stone be placed
in the Position c d, with its repelling End downwards; then the Island will be driven upwards obliquely towards D. When
it is arrived at D, let the Stone be turned upon its Axle till its attracting End points towards E, and then the Island will be
carried obliquely towards E; where if the Stone be again turned upon its Axle till it stands in the Position E F, with its
repelling Point downwards, the Island will rise obliquely towards F, where by directing the attracting End towards G, the
Island may be carried to G, and from G to H, by turning the Stone, so as to make its repelling Extremity point directly
downwards. And thus by changing the Situation of the Stone as often as there is Occasion, the Island is made to rise and
fall by Turns in an oblique Direction; and by those alternate Risings and Fallings (the Obliquity being not considerable), is
conveyed from one Part of the Dominions to the other.

 But it must be observed, that 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 Perfection with other Parts
of Astronomy.

 The King would be the most absolute Prince in the Universe, if he could but prevail on a Ministry to join with him, but
these having their Estates below on the Continent, and considering that the Office of a Favourite hath a very uncertain
Tenure, would never consent to the enslaving their Country.

 If any Town should engage in Rebellion or Mutiny, fall into violent Factions, or refuse to pay the usual Tribute; the King
hath two Methods of reducing them to Obedience. The first and the mildest Course is by keeping the Island hovering
over such a Town, and the Lands about it; whereby he can deprive them of the Benefit of the Sun and the Rain, and
consequently afflict the Inhabitants with Dearth and Diseases. And if the Crime deserve it, they are at the same time
pelted from above with great Stones, against which they have no Defence, but by creeping into Cellars or Caves, while
the Roofs of their Houses are beaten to Pieces. But if they still continue obstinate, or offer to raise Insurrections, he
proceeds to the last Remedy, by letting the Island drop directly upon their Heads, which makes a universal Destruction
both of Houses and Men. However, this is an Extremity to which the Prince is seldom driven, neither indeed is he willing,
to put it in Execution; nor dare his Ministers advise him to an Action, which as it would render them odious to the
People, so it would be a great Damage to their own Estates that lie all below; for the Island is the King's Demesne.

 But there is still indeed a more weighty Reason, why the Kings of this Country have been always averse from executing
so terrible an Action, unless upon the utmost Necessity. For if the Town intended to be destroyed should have in it any
tall Rocks, as it generally falls out in the larger Cities; a Situation probably chosen at first with a View to prevent such a
Catastrophe:; Or if it abound in high Spires or Pillars of Stone, a sudden Fall might endanger the Bottom or under
Surface of the Island, which, although it consists as I have said, of one entire Adamant two hundred Yards thick, might
happen to crack by too great a Choque, or burst by approaching too near the Fires from the Houses below; as the
Backs both of Iron and Stone will often do in our Chimneys. Of all this the People are well apprized, and understand
how far to carry their Obstinacy, where their Liberty or Property is concerned. And the King, when he is highest
provoked, and most determined to press a City to Rubbish, orders the Island to descend with great Gentleness, out of a
Pretence of Tenderness to his People, but indeed for fear of breaking the Adamantine Bottom; in which Case it is the
Opinion of all their Philosophers, that the Load-stone could no longer hold it up, and the whole Mass would fall to the
Ground.

 [About three Years before my Arrival among them, while the King was in his Progress over his Dominions, there
happened an extraordinary Accident which had like to have put a Period to the Fate of that Monarchy, at least as it is
now instituted. Lindalino the second City in the Kingdom was the first his Majesty visited in his Progress. Three Days
after his Departure, the Inhabitants, who had often complained of great Oppressions, shut the Town Gates, seized on the
Governor, and with incredible Speed and Labour erected four large Towers, one at every Corner of the City (which is
an exact Square) equal in Heigth to a strong pointed Rock that stands directly in the Center of the City. Upon the Top of
each Tower, as well as upon the Rock, they fixed a great Loadstone, and in case their Design should fail, they had
provided a vast Quantity of the most combustible Fewel, hoping to burst therewith the adamantine Bottom of the Island,
if the Loadstone Project should miscarry.

 It was eight Months before the King had perfect Notice that the Lindalinians were in Rebellion. He then commanded
that the Island should be wafted over the City. The People were unanimous, and had laid in Store of Provisions, and a
great River runs through the middle of the Town. The King hovered over them several Days to deprive them of the Sun
and the Rain. He ordered many Packthreads to be let down, yet not a Person offered to send up a Petition, but instead
thereof, very bold Demands, the Redress of all their Grievances, great Immunitys, the Choice of their own Governor,
and other like Exorbitances. Upon which his Majesty commanded all the Inhabitants of the Island to cast great Stones
from the lower Gallery into the Town; but the Citizens had provided against this Mischief by conveying their Persons and
Effects into the four Towers, and other strong Buildings, and Vaults under Ground.

 The King being now determined to reduce this proud People, ordered that the Island should descend gently within
fourty Yards of the Top of the Towers and Rock. This was accordingly done; but the Officers employed in that Work
found the Descent much speedier than usual, and by turning the Loadstone could not without great Difficulty keep it in a
firm Position, but found the Island inclining to fall. They sent the King immediate Intelligence of this astonishing Event and
begged his Majesty's Permission to raise the Island higher; the King consented, a general Council was called, and the
Officers of the Loadstone ordered to attend. One of the oldest and expertest among them obtained leave to try an
Experiment. He took a strong Line of an hundred Yards, and the Island being raised over the Town above the attracting
Power they had felt, He fastened a Piece of Adamant to the End of his Line, which had in it a Mixture of Iron mineral, of
the same Nature with that whereof the Bottom or lower Surface of the Island is composed, and from the lower Gallery
let it down slowly towards the Top of the Towers. The Adamant was not descended four Yards, before the Officer felt it
drawn so strongly downward, that he could hardly pull it back. He then threw down several small Pieces of Adamant,
and observed that they were all violently attracted by the Top of the Tower. The same Experiment was made on the
other three Towers, and on the Rock with the same Effect.

 This Incident broke entirely the King's Measures and (to dwell no longer on other Circumstances) he was forced to give
the Town their own Conditions.

 I was assured by a great Minister, that if the Island had descended so near the Town, as not to be able to raise it self,
the Citizens were determined to fix it for ever, to kill the King and all his Servants, and entirely change the Government.]

 By a fundamental Law of this Realm, neither the King, nor either of his two elder Sons, are permitted to leave the
Island; nor the Queen, till she is past Child-bearing.