鏂版蹇佃嫳璇涓夊唽
Lesson42
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銆愯鏂囥�?/p>
Cave exploration, or potholing, as it has come to be
known, is a relatively new sport. Perhaps it is the desire
for solitude or the chance of making an unexpected discovery
that lures men down to the depths of the earth. It is
impossible to give a satisfactory explanation for a pot-
holer's motives. For him, caves have the same peculiar
fascination which high mountains have for the climber. They
arouse instincts which can only be dimly understood.
Exploring really deep caves is not a task for the Sunday
afternoon rambler. Such undertakings require the precise
planning and foresight of military operations. It can take as
long as eight days to rig up rope ladders and to establish
supply bases before a descent can be made into a very deep
cave. Precautions of this sort are necessary, for it is
impossible to foretell the exact nature of the difficulties
which will confront the potholer. The deepest known cave in
the world is the Gouffre Berger near Grenoble. It extends to
a depth of 3723 feet. This immense chasm has been formed by
an underground stream which has tunnelled a course through a
flaw in the rocks. The entrance to the cave is on a plateau
in the Dauphine Alps. As it is only six feet across, it is
barely noticeable. The cave might never have been discovered
had not the entrance been spotted by the distinguished French
potholer, Berger. Since its discovery, it has become a sort
of potholers' Everest. Though a number of descents have been
made, much of it still remains to be explored.