Yellow Sea, an important inlet of the Pacific Ocean, washes the northeastern coast of China and is bounded on the west by the Chinese provinces of Shangtung and Keang-su and on the east by the peninsula of Korea and by Japan. It is more than 600 miles in length and about 400 in average breadth. Its waters are shallow and are gradually becoming still shallower, owing to the deposits of earth borne down into it by Hoang-ho and Yang-tse-Kiang Rivers.