The regions lying north and south of Gobi contain many salt lakes, none of them individually comparing with the Aral Sea, but collectively covering a much larger extent, and most of them receiving the waters of the streams which drain their own isolated basins. The peculiarities of these little known parts, especially the depression on each side of the Tien shan, are such as to render them among the most interesting fields for geographical and geological research in the world. The largest one in Turkestan is Lob-nor, stated to be a great marsh overgrown with tall reeds and having a length of 75 miles and width of 15 miles.[13] Bostang-nor, said to connect with this lake, is placed on Chinese maps some 30 miles north of it. North of the Tien shan the lakes are larger and more numerous; the Dzaisang, Kisil-bash and Issik-kul are the most important. All these lakes are salt. The whole region of Koko-nor is a country of lakes. The Oling and Dzaring are among the sources of the Yellow River; and the _Tsing hai_, or Azure Sea, better known as Koko-nor, gives its name to the province. The Tengkiri-nor in Tibet lies to the north of H’lassa, and is the largest sheet of water within the frontiers of the empire. In its neighborhood are numerous small lakes extending northward into Koko-nor. The Palti or Yamorouk is shaped like a ring, an island in its centre occupying nearly the whole surface. Ulterior Tibet possesses many lakes on both sides of the Gang-dis-ri range; the Yik and Paha, near Gobi, are the largest, being only two of a long row of them south of the Kwănlun range. ~BOUNDARIES OF THE PROVINCES.~ The Eighteen Provinces are bounded on the north-east by the colony of Shingking, from which they are separated by the line of a former palisade marking the boundary from the town of Shan-hai kwan to the Hwang ho. Following this stream to its sources in the Ín shan, the boundary then crosses these mountains and pursues a west and south-west course, through the territories of roving Mongol tribes, until it finds the Yellow River at the settlement of Hokiuh in Shensí. West of this the Great Wall divides the provinces of Shensí and Kansuh from the Mongolian deserts as far as the Kiayü Pass, beyond which lies the desert of Gobi, called _Peh hai_ (North Sea) and _Hah hai_ (Black Sea). On the east are the Gulf of Pechele and the Yellow Sea or _Hwang hai_, also called _Tung hai_ (Eastern Sea) as far south as the Channel of Formosa. This channel and the China Sea lie on the south-east and south, as far as the Gulf of Tongking and the confines of Annam. Kwangsí and Yunnan border on Annam and Siam on their south sides, while Burmah marks the western frontier, but nearly the whole south-west and western frontiers beyond Yunnan and Sz’chuen are possessed by small tribes of uncivilized people, over whom neither the Chinese nor Burmese have much real control. Koko-nor bounds Sz’chuen and Kansuh on their western and south-western sides. ~CHARACTER OF THE COAST.~