i:\sri i:\ i rig ki-hafmi Y, 



separating il from Assam. The longitudes of 92* and 109* E, mark 

 its extreme western and eastern limits on the Bay of Bengal and 

 China Hen, the total length in the direction from uurth to south 

 lieiaij* about 800 miles, from tho Chinese frontier to the I- r I u.u- 

 of Kra, and 950 at its broadest part, between the Ganges delta and 

 tiulf of Tonkin, with on approximate area of about 800,000 sqttttfO 



Mountain Systems.— The salient physical features of this 

 region present a certain simplicity of outline, as shown especially 

 in the uniform and nearly parallel deposition of its mountain 

 ranges ami river valleys, which run mainly in the direction of its 

 long axis from north-west to south-east. Projecting like Southern 

 China, with which it forms a geographical unit, from the elevated 

 Tibetan plateau, the peninsula, is of an extremely rugged character 

 in its northern Motion, where it begins to fnll rapidly towards the 

 central plains. Here the «1ope of the land is clearly indicated by 

 the numerous fid Is and rapids obstructing the upper courses of the 

 main streams and their chief affluents. But the mountain chains 

 forming the water-partings between these river basins, although 

 seldom I'Xn-ediiig TOGO <>r 8000 feet, maintain u mean clev.-ttiu'i of 

 from 6000 to G0O0 feet throughout their whole course to the Malay 

 Peninsula* 



In the north -vest the Abakan Yoma range, Rcparaiinj; tin- Amfcnn 

 eaustlands from Upper Bunnah, has several crests trom 6tUiO to 7000 fat 

 high, culminating in the Mnlseloi Mon or "Blue Mountain " (7100 feet) 

 in tho Lushai country. This range, which terminates at Capo jNegniiH at 

 tin- western iiii^U' nf tU»> IruwaiMy <h'ha, U crossed hy several parses, of 

 which one of the most frequented is that of Ayeng (under IMO Hit) 

 leading from the coast to Upper Bunnah. The prevailing formntiotu* am 

 limestones and santhttoncs of the chalk and lertinry periods intcrNperaod 

 with soma eruptive recks, hut no active volcanoes. But on tha coaM and 

 adjacent archipelago are grouped a large number of mud volcanoes, as 

 many as fifteen In the island nf Bund alone, all subject to freipient and 

 violent eniptions, 



Parallel and oust of the Arakau Yotua hi the Pk«i* Yoma range, 

 forming the divide between the Irawadily and Sittang basins, hut wMwu 

 exceeding 2000 fecL Southwards it uwrgrn in the extensive plain of 

 Pegu, formed by the united lower valleys and deltas of the Irawaddy and 

 Sittang, and stretching from Capo Negrais to Martabnn west and east. 

 The Pegu Yoma, one of whoso crests* me Puppa or Pappa Dting (30Q0 

 feet), presents tho character of a» extirt.-t volcano, is continued northwards 

 by I he Shax-Yoma, which se| myitis tin- walrra flowing west to the 

 Irnwaddy and Sitting butn fmjii those draining east to the Snlwin. This 

 range, which risen in tho north to over 10,000 feet, and even in the sunith 

 has one peak, tho Nattung, S » f.-e: hi^h, ij.] mrs to consist mainly of 

 slaty clays alternating with sandstone, wad Wre and there assuming a 

 hankie diarai Ur. Strati lied sandstone* interbreed witli veins of quarts 

 are also a prevailing feature of the Tenasat'rim hills, which form a southern 



