The annexed wood-cut exhibits a
longitudinal section of the glacier, in which this difference in the
motion of the upper and lower portions of the mass is represented, the
beds being almost horizontal in the upper snow-fields, while their lower
portion slopes move rapidly downward in the _neve_ region, and toward
the lower end the upper portion takes the lead, and advances more
rapidly than the lower.
[Illustration]
I presented these results for the first time in two letters, dated
October 9th, 1842, which were published in a German periodical, the
Jahrbuch of Leonhard and Bronn. The last three wood-cuts introduced
above, the transverse and longitudinal sections of the glacier as well
as that representing the concentric lines of stratification on the
surface, are the identical ones contained in those communications. These
papers seem to have been overlooked by contemporary investigators, and I
may be permitted to translate here a passage from one of them, since it
sums up the results of the inequality of motion throughout the glacier
and its influence on the primitive stratification of the mass in as few
words and as correctly as I could give them to-day, twenty years
later:--"Combining these views, it appears that the glacier may be
represented as composed of concentric shells which arise from the
parallel strata of the upper region by the following process.
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