SIAM, in Asia, including the countries tributary to or dependent on it, extends from 4° to 22° N. lat., 93° to 105° 20' E. long. It com prehends a vast extent of country in the peninsula beyond the Ganges, and the larger part of the Malay peninsula. It is bounded E. by the kingdom or Cochin-China, or Annam ; N. by the province of Yunnan, China, and that part of Laos which is subject to the Ilirmans; W. by the Birman empire, from which it is separated by the river Salueu, tho British province of Tenasserim, and the Gulf of Bengal ; and S.
by the independent states of the Malay peninsula, Perak, and Pahang. The area is very variously estimated, but is probably not less than 250,000 square miles. The population was estimated by Crawford at 2,790,000, but more recent travellers estimate it at from 5,000,000 to 6,000,000, which is probably much more nearly correct.
Surface, d'•c.—Siam possesses a great extent of coast. That portion of the Indian Ocean which is called the Gulf of Siam, and extends from south-east to north-west above 500 miles, with an average width of about 250 miles, is almost entirely surrounded by the countries subject to Siam. The Gulf of Bengal forme a coast-line of 529 miles; and the Indian Ocean, with the Gulf of Siam, one of 1467 miles.
A considerable portion of Siam is covered with mountains and hills. The mountainous and hilly part appears to be connected with two chains of mountains, running south and north, and terminating at their northern extremity in the snow-covered mountain ranges which surround the elevated table-land that forms the centre of the Chinese province of Yunnan. Between these two ranges lies the wide valley of the river Mermn.
The western of the two groat chains, called by geographers the Mountains of Siam, seposates the basins of the rivers Sallie!' and Menam, and occupies also the northern portion of the Malay peninsula, as far south as 11° N. lat. Towards its southern extremity (between 15° and 12° N. lat.), it is probably not more than 70 miles across, but is divided into two ridges, which inclose the narrow valley in which the Tcnasserim River rune southward. The whole of this range appears to be covered with jungle or high trees. Some of the summits rise, according to a vague estimate, to between 5000 and 6000 feet. The ridge which extends along the eastern banks of the Tenasserim River is called by the Siamese Sam-ralot, or the Three Hundred Peaks.' It consists of lofty mountains, extremely rugged
on their flanks as well as summits, and rising in innumerable bold conical peaks. This ridge, which lowers considerably as it approaches Kwi Point (12° N. lat.), does not come near the Gulf of Siam, but leaves between it and the shores a level country, apparently alluvial, on which rise some insulated peaks. The mountains of Slain termi nate near 11° N. let., on the isthmus of Krah. Three passes are known to lead over these mountains between Tenasserim and Siam, but only one of them seems adapted to facilitate the intercourse between the two countries. It leads from Molmcin, near the con fluence of the river Ataran with the Sallie!), along the banks of the Ataran to its source, where the range is passed at a place called Prasong-tshu, or the ' Three Pagodas.' Thence it passes into Siam, and traverses the rich and fertile valley of the river Mekhlotag nearly to its mouth, at the town of the same name.
The high ground which traverses the isthmus of Krah from north to south, extending from 12° to 9° N. lat., can hardly be called hilly. It is separated from both the mountains of Siam and those of the Malay peninsula, which lie north and south of it, by deep and wide deproadoes. The northern of these depressions occurs near N. 1st., where the ground that separates the Patchett River, which falls into the Gulf of Bengal, and the Choomphon River, which enters the Gulf of Siam, is so low, that., according to the statement of the natives, the two rivers often unite their waters during the spring-tides. Both rivers are navigable for boats, and they could be readily so con nected as to constitute a abort and direct water-communication across the isthmus between the Bay of Bengal and the Gulf of Siam. The southern depression occurs at the southern extremity of the isthmus of Krab, and crosses the peninsula obliquely from the Bay of Bengal, east of l'hunga, or Tonga (Se 15' N. lat.), running north-east to the town of Pollnow, east of which It expands to a great width, compre hending the low country on both sides of the river Thakham, between the towns of Pti000•phin and Chai-ya.