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difference of elevation in those parts, but that these wrinkles are the 

 cause of that difference of colour ; the more watery parts draining 

 from the ridge, leave that rough, and form a smooth alluvium in the 

 hollow. 



Applying these facts to the glaciers, Mr Milwai'd supposes that 

 the dirt-bands, i.e. the bands of alternate compact and porous ice, 

 must be accompanied by a similar difference of elevation, which, 

 though destroyed by the action of the sun on the lower parts, may 

 yet be visible near the origin of the glaciers in the early spring ; 

 and he further supposes that the bands may be formed, in the first 

 instance, by the irregular descent of the neve in winter and summer, 

 so that they become in fact the annual rings of the glacier, shewing 

 its age and rate of increase. 



3. On the rate of Progression of the Himalayan Glaciers. 

 By Lieutenant R. Strachey, Bengal Engineers. 



Mr Strachey's letter contained some interesting observations which 

 he has been makmg on the motions of the glaciers in the Himalayan 

 mountains ; and his measures, conducted on the plan of Professor 

 Forbes in the Alps, are the earliest that have been taken in Asia. 

 The Pinduree glacier, on which the observations were made during 

 cold weather, was found to move 3 feet 1 inch in 5 days at the centre, 

 and at the sides about 1 foot 5 inches. 



Lieutenant Strachey's former Researches on the Glaciers of the 

 Kumaon Himalaya (published in one of the Indian Journals), have 

 satisfactorily proved the existence of glaciers in lat. 30° 20', which 

 present in detail all the phenomena of those of Europe. 



4. Observations on the preceding Communications, and espe- 

 cially on the cause of the Annual Rings of Glaciers. By 

 Professor Forbes. 



Professor Forbes stated that Mr Milward's shrewd suspicion of 

 the bands of ice of different consistence being accompanied also by 

 wrinkles or elevations, had been discovered by himself some years 

 before, at the very place and time pointed out as most likely ; and 

 he shewed that, while there is a tendency in a tenacious viscous fluid 

 to produce wrinkles, under pressure capable of effecting detrusion, 



