How did Gulliver head towards Japan?

Gulliver went to Japan by ship.

In six days I found a vessel ready to carry me to Japan, and spent fifteen days in the voyage. We landed at a small port-town called Xamoschi, situated on the south-east part of Japan; the town lies on the western point, where there is a narrow strait leading northward into along arm of the sea, upon the north-west part of which, Yedo, the metropolis, stands.