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marking the additions which the icy mass had annually received, 

 each layer being the accumulated snow of one year ; but that, as 

 the Meteorological Tables kept at the Hospice of the Great St Ber- 

 nard shewed that from 300 to 700 inches of snow fell during the 

 six winter months, it seemed possible that each layer marked the 

 separate storms of snow ; or, if they marked the annual accumula- 

 tions, they apparently proved, what had not previously been sus- 

 pected, that snow and ice waste nearly as rapidly in the upper as 

 they do in the lower regions. 



2. Vertical and Longitudinal Strata. The author stated that 

 these strata were always of great tenuity, were more or less perpen- 

 dicular, but had always a direction parallel with the retaining wall 

 or length of the glacier. Their mode of foi'mation he attributed to 

 the onward movement of the glacier leaving narrow spaces interven- 

 ing between the sides of the already formed icy mass and the flanks 

 of the valley, which, being filled up with the loose and softened 

 snow lying on the sloping flanks, was, from the falling of the tem- 

 perature during the night, and from contact with the already formed 

 icy mass, converted into a layer of solid ice. From the thinness of 

 these layers, the author regarded them as marking the additions 

 which had been daily made to the glacier. The author also stated 

 that it would, in all probability, be found that, wherever pillars, pyra- 

 mids, or needles of ice were met with, this structure would be found 

 present ; as the fissures, which always crossed the glacier from side 

 to side, divided it into transverse sections, which, when unequally 

 supported below, would split into smaller fragments in the planes of 

 their stratification, so that each fragment would necessarily assume 

 the form of a vertical prismatic column. 



3. A combination of the Horizontal with the Vertical and Lon- 

 gitudinal Strata. The author stated that, as the mass composed of 

 the horizontal strata of the upper regions slowly advanced to the 

 lower ones, it received, in the manner above stated, a lateral increase, 

 which, at the same time that it increased its breadth, probably also 

 added to its depth. That, as the glacier continued to advance, the 

 horizontal strata, which lay uppermost, would melt away first, so 

 that at one point they would only be observed in the middle of the 

 glacier, and lower down even completely disappear. He mentioned 

 several facts which seemed to pi'ove his position. 



4. Transverse more or less inclined Strata. The author stated 



