Answer: a giant eagle.
When on tour of the South coast of the Kingdom of Brobdingnag, Gulliver goes down to the beach with a servant. At this point, Gulliver really wants to go home, as it has been two years since he arrived at the kingdom. As Gulliver is relaxing in his box, a giant eagle comes and picks him up. the eagle eventually drops the box at sea, and Gulliver is rescued by some sailors who are his same size.