how did guliver reach the flotig island

Gulliver was drawn up and onto the island with the use of pulleys.

They made signs for me to come down from the rock, and go towards the shore, which I accordingly did; and the flying island being raised to a convenient height, the verge directly over me, a chain was let down from the lowest gallery, with a seat fastened to the bottom, to which I fixed myself, and was drawn up by pulleys.