58 JSailstorm at Shamnagar. [Mabch, 



nagar, on the Eastern Bengal Line. The storm was apparently from the 

 south-west and lasted only a few minutes, leaving the ground fairly even- 

 ly strewn with hailstones, on an average about 4 to 5 inches apart. It is 

 the size of the hailstones, however, that forms the remarkable feature in 

 the occurrence. They were mostly of about the bulk of pigeons', and small 

 Indian hens', eggs, but generally flattened in shape, though some were 

 much larger. The largest one, out of some 40 or 50 which were collected 

 at random, measured, about 20 minutes after the fall and when it had melt- 

 ed considerably from handling, 3i inches in length and over 2 inches 

 lateral diameter. 



This stone and all the larger ones consisted of a distinct, radiated, 

 opaque nucleus, translucent in its centre, a spheroidal disc in shape and about 

 li inches in its largest diameter, surrounded by clear prismatic ice, with 

 the edges more or less melted. One hailstone was brought to me imme- 

 diately after it fell, about 2^ inches in diameter, almost spherical, with all 

 the massive surrounding crystals edged and pointed. It had the appear- 

 ance of the spiked ball at the end of the flail wielded in ancient warfare. 

 The smaller stones consisted of the nucleus only, and the larger sizes 

 depended upon a greater or less bulk of crystalline ice adhering to it. 



I regret there was no opportunity to weigh the hailstones, but they 

 were of a very hard, massive character. 



Me. Blanford said that the hailstones described by Mr. Simson were 

 undoubtedly of large size but by no means unprecedented. He had him- 

 self on two occasions described and figured in the Society's Journal hail- 

 stones of equal or nearly equal dimensions, aud much larger stones had 

 been described by others. The form and structure of the stones described 

 in the letter were such as he had observed himself on several occasions. In 

 general, large stones had an opaque nucleus, consisting of snow crystals with 

 included air ; and the outer part of large stones observed by him almost 

 always consisted of transparent ice, frequently enclosing air bubbles ; and 

 also, frequently, with numerous projections which bore much resemblance 

 to half melted crystals. He had, however, never actually identified the well 

 known hexagonal prismatic form (which is that in which water crystallizes) 

 in these pseudo-crystals. In many cases, although not always, the portion 

 immediately surrounding the nucleus consisted of concentric shells of 

 opaque and transparent ice alternately. The formation of hailstones 

 of such large size could not yet be said to be satisfactorily explained. The 

 theory of Professor W. Ferrel appeared the most probable of those hither- 

 to put forward. It supposed that hailstones were caught up in rotating 

 convection currents of great violence, similar to those in a water-spout, and 

 were thus kept suspended in the atmosphere long enough to allow 

 of their receiving repeated accretions of condensed vapour, sufficient in the 



