Gulliver's explains how the Flying Island moves by giving what he calls "a philosophical account" of its movement capabilities. The explanation is quite complicated, but the movement principle is quite simple and is based upon magnetic forces in the Flying Island and in the country below (Balnibarbi). These forces, working in opposition, allow the island to move up, down, forward, backward, and sideways by means of using the attracting and repelling principles inherent in the science of magnetism. Gulliver also explains how the King uses the Flying Island to tyrannize the people of Balnibarbi. He can cut off sunshine and rain from any region on the lower island. Or, if he wishes, he can pelt it with stones. Theoretically, he could lower Laputa and crush Balnibarbian towns. Finally, Gulliver relates the story of the successful rebellion of the city of Lindalino.
