262 S. E. Peal — On Movements of Clouds in Tipper Assam. [Dec. 



gravelly, all through seemingly ; and rests on sandstones, bedded and seen 

 on the level of the river, — and not above, as far as I can see. How these 

 great blocks of dark grey rock got up on the hill top was the puzzle to me. 

 They seem scattered about on its surface, top and sides ; and the hill is 

 isolated, not overhung by any higher land. * * * The blocks of horn- 

 blende are probably up to 4 or 5 tons, now and then, and both isolated and 

 grouped ; quite irregular and more or less angular. They seemed to me like 

 the blocks carried along a glacier surface. However, it may, after all, be 

 easily soluble by some other means, and not need a large glacier to account 

 for it. * * * These gravelly hills are not common in Upper Assam, which 

 is a dead flat ; not a stone of any sort to be seen." 



Mr. Blanford said that the sketches of contorted and coloured sands 

 which Mr. Peal had sent, certainly reminded one much of certain superficial 

 deposits of the English river valleys, which were attributed to the action of 

 ice. But he was hardly prepared to accept the idea of a great glacier filling 

 the Assam valley, without very much stronger evidence. If the structure 

 described be really due to ice action, it would demand a change of climate of 

 less magnitude, to suppose that the deposits were due to river ice in winter. 

 Perhaps a climate which admitted of glaciers in the Naga hills down to 

 4,500 feet, as described by Major Godwin- Austen,* might also admit of 

 river ice, in winter, within 500 feet of the present sea-level. 



The last extract read had reference to "the drift of the clouds in Upper 

 Assam. Mr. Blaistord said that he had suggested this class of observations 

 to Mr. Peal, with a view to verifying the suggestion made in a paper on 

 the Physical Explanation of the Inequality of the two semidiurnal Barome- 

 tric Tides, published in the 45th volume of the Society's Journal ; viz., that 

 there was a flow of air in the day-time from over the valleys, to the moun- 

 tains on either side, and a return flow at night. Mr. Peal writes — " About 

 winds, I can tell you that I have pretty steadily had my eye on the clouds, 

 upper and lower, since your last, and am still more struck than ever, with 

 the remarkable regularity of the flow and counter-flow. The night winds 

 (if any) travel steadily and slowly from the SSW. or WSW. (within 

 three points) and do not change till 9 or 9^ a. M. when a counter- current 

 sets in from the very opposite point, say NE. to NNE. This continues 

 more or less all day, as a surface and upper wind, but I can see no trace of 

 a wind to or from the hills, and never remember to have noticed such a 

 wind, except in squalls, and I am pretty near a good mass of hills that 

 should shew any thing of the kind. Our worst squalls are from the NW. 

 * * * * As the cold season comes on, I find the NE. wind begins ear- 

 lier. It is, at times, now seen at 8 A. M. but seen above and not felt below 

 where all is still and under a dense fog. As the sun rises, the latter dissi- 



* Journ, As. Soc. Bengal, Vol. xliv, Part 2, p. 209. 



