534 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY , Vol. XII. 



was found to be the same as at about 800 fathoms, viz., 41 deg. F. The 

 explanation of this curious but well recognised state of affairs is that the 

 coldness of the deep-sea water is solely due to a flow influx of the cold 

 heavy Antarctic waters creeping along the bed of the ocean from the polar 

 to the tropical regions. Should any barrier be encountered by this moving 

 mass of water, it would obviously either stop the movement, or force the 

 water up into the warmer water corresponding to the depth of tlie top of the 

 barrier below the surface. And this is actually the state of affairs in the 

 Andaman Sea, The only very deep channel affording communication 

 between the depths of this sea and the Bay of Bengal is the channel between 

 Sumatra and the Nicobars. The survey of this channel is incomplete, but 

 what soundings there are show that there is probably a ridge uniting the 

 opposite sides of the channel at a depth not exceeding 900 fathoms, roughly. 

 Hence, all the water below the depth of 900 fathoms within the enclosed 

 Andaman Sea is at the uniform temperature of 41° F. — the temperature of 

 water at about the same depth in the Bay of Bengal; while outside, in 

 the open Bay of Bengal, the temperature gradually diminishes as the depth 

 increases. 



After coaling and provisioning, the InvesUgator at once left for Moulmein, 

 The preliminary work for the survey of the river was of an arduous descrip- 

 tion, involving long tramps across the steaming paddy fields to the low hills 

 on either side of but a few miles distant from the river, Moulmein itself is 

 a most picturesquely situated town, viewed from the river. On a bright cold- 

 weather morning few scenes could exceed the beauty of the green foliage, 

 with the most graceful, glittering, and slender spires of pagodas overtopping 

 the trees and the pagoda-crowned ridge -overshadowing the long struggling 

 town. To the east and up tlie Salween are the high hills close to the borders 

 of Siam, while to the north and west lies the fertile Bruxe Island with its 

 range of low-wooded hills. The rumerous hills rising to the eastwards of 

 Moulmein have a most curious appearance as they rise straight out of the 

 perfectly level surrounding country, often to a height of a thousand or more 

 feet. They are mostly of limestone formation, and are often locally celebrat- 

 ed for their large caves, ornamented with stalactites and stalag- 

 mites and frequently forming the roosting places of enormous numbers of 

 bats, the guano of which is collected and sold, A similar hill to these near 

 Kollado, the nearest outport to Karennee, actually has a small stream running 

 right through its base. On the top of many of these limestone hills lives the 

 Burmese serow, an animal seldom obtained by English sportsmen although 

 often trapped and killed by the Karens, While lying at anchor off the town 

 of Moulmein the high spring November tides brought down quantities of 

 drift-wood and on threesuccessive mornings there were taken from the paddle 

 box snakes, which had journeyed down as passengers on the drift-wood and 

 been checked in their downward course by our paddle floats. On another 



