The general thickness of the sheet is from a foot to a
foot and a half; and this is the chief source from which the _fermier_
draws the ice, as it is much more easily quarried than the solid
floor. Some of my friends went to the cave a few weeks after my visit,
and found that the whole sheet had been pared off and carried away. On
some parts of the wall the sheet was not completely continuous, being
formed of broad and distinct cascades, connected by cross channels of
ice, and uniting at their upper and lower ends, thus presenting many
curious and ornamental groupings. On cutting through this ice, it was
found not to lie closely on the rock, a small intermediate space being
generally left, almost filled with minute limestone particles in a
very wet state; and the whole cavern showed signs of more or less
thaw.
[Illustration: THE GLACIERE OF S. GEORGES. VERTICAL SECTIONS OF THE
GLACIERE OF S. GEORGES.]
It was natural to examine the structure of the ice in this glaciere,
after what we had observed on La Genolliere. The same prismatic
structure was universal in the sheet on the wall, and in the blocks
which lay here and there on the floor and formed the sole remains of
former columns.
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