John of Montecorvino, working mainly alone, has made numerous converts to Christianity and has translated the New Testament into Uighur.

In 1299, he builds a church at Khanbaliq.

Marco Polo, in his “Travels,” describes a Chinese junk, praising its system of bulkheads.

In use since before the ninth century, when these crafts were carrying merchants to Indonesia and India, junks lack three components—the keel as well as the stemposts and sternposts (upright beams at the bow and the stern)—that are basic to other types of ships.

Strong and seaworthy, the junk (the term is probably derived from the Chinese Chuan, "boat," via Malay djong) has a hull that is partitioned off by solid plank walls, or bulkheads, running both lengthwise and crosswise, dividing the junk into watertight compartments and giving it structural rigidity.

A deep, heavy rudder, mounted so that it can be raised and lowered, compensates for the lack of a keel.

Masts, numbering from one to five, carry the sails, which are constructed of narrow, horizontal sheets of linen or of matting panels.

Each panel has its own sheet, or line, thus helping to distribute the wind's force, and each sail can be rapidly spread or closed.