A Voyage to Laputa, Balnibarbi, Luggnagg, Glubbdubdrib and Japan

"A Voyage to Laputa, Balnibarbi, Luggnagg, Glubbdubdrib and Japan" is a novel by Jonathan Swift: Setting out again, Gulliver's ship is attacked by pirates, and he is marooned close to a desolate rocky island near India. He is rescued by the flying island of Laputa, a kingdom devoted to the arts of music, mathematics, and astronomy but unable to use them for practical ends. Rather than use armies, Laputa has a custom of throwing rocks down at rebellious cities on the ground.