Proceedings of the Asiatic Soc. of Bengal. [September, 



Grey, proposed by Lieut, -Colonel D. C. Phillott, seconded by 

 Mr. G. JEL Tipper ; Mr. L. P. Walts, proposed by Mr. D. 

 Hooper, seconded by Mr. G. H. Tipper; Mr. F. H. Gravely, 

 proposed by Dr. N. Annandale, seconded by Mr. T. H. D. 

 LaTouche; Captain A. Fortescue, R.A.M.C., proposed by Mr. 

 T. H. D. LaTouche, seconded by Dr. N. Annandale. 



The President gave a brief description, illustrated with 

 diagrams and lantern slides, of the Lonar Lake, situated in the 

 Berars, near the northern limits of Hyderabad State. The lake 

 basin is a circular depression, a little over a mile in diameter 

 and some 300 feet deep, in the surface of the Deccan trap, the 

 expanse of basaltic rock that covers so wide an area in the cen- 

 tral and western portions of the Indian Peninsula. This for- 

 mation is built up of practically horizontal flows of lava which 

 are supposed to have welled out from fissures in the underlying 

 rocks in early Tertiary times, when the old continent of Gond- 

 wana land, of which the Indian Peninsula and South Africa 

 are remnants, was being broken up ; for nothing of the nature of 

 a volcanic cone has been discovered. The origin of the Lonar 

 Lake basin has been attributed to a sudden and violent explo- 

 sion, which is supposed to have blown out the surfacs layer of 

 trap, leaving the present hollow, but there are serious objec- 



to the acceptance of this theory. If such an explosion 



jccurred, we would expect to find accumulations of the 



rocks and scoriae blown out in the neighbourhood of the hollow, 

 but nothing of the kind exists except a slightly raised rim of 

 loose blocks which may be merely weathered fragments of the 

 solid lava. Moreover, we would expect to find some indication 

 of a deep crater in the centre of the depression, whereas the 

 floor of the basin is practically level, and the water of the lake 

 no more than two feet deep at any point in the dry season. 



The theory advanced by the President suggests that a previ- 

 ously existing layer of lava at this spot was raised bodily by the 

 injection of molten rock from below, forming a huge u blister 

 on the surface; and that before this fresh lava was cooled and 

 consolidated, a fissure opened through which it escaped, and 

 that the crown of the dome then broke down and subsided, 

 forming a circular pan-shaped hollow with a level floor. Some 

 con6rmation of this suggestion is afforded by the fact that the 

 lake is surrounded by a series of springs, indicating that the 

 rock beneath is traversed by vertical fissures parallel to the 

 encircling walls. 



The lake has no outlet, and the water is strongly impreg- 

 nated with salts, mainly carbonate of soda, which was for- 

 merly in great request for the manufacture of a cheap glass 

 used Drmeinallv for tli« makino- nf hanalpq. hut the industry 



tions 

 had 



s now been : 

 ported soda 



