But proof after proof was furnished, and finally the world had to believe.
The wise men not only said the glacier moved, but they timed its movement. They ciphered out a glacier's gait, and then said confidently that it would travel just so far in so many years. There is record of a striking and curious example of the accuracy which may be attained in these reckonings.
In 1820 the ascent of Mont Blanc was attempted by a Russian and two Englishmen, with seven guides. They had reached a prodigious altitude, and were approaching the summit, when an avalanche swept several of the party down a sharp slope of two hundred feet and hurled five of them (all guides,) into one of the crevasses of a glacier. The life of one of the five was saved by a long barometer which was strapped to his back—it bridged the crevasse and suspended him until help came. The alpenstock or baton of another saved its owner in a similar way. Three men were lost—Pierre Balmat, Pierre Carrier, and Auguste Tairraz. They had been hurled down into the fathomless great deeps of the crevasse.
Dr. Forbes, the English geologist, had made frequent visits to the Mont Blanc region, and had given much attention to the disputed question of the movement of glaciers. During one of these visits he completed his estimates of the rate of movement of the glacier which had swallowed up the three guides, and uttered the prediction that the glacier would deliver up its dead at the foot of the mountain thirty-five years from the time of the accident, or possibly forty.
A dull, slow journey—a movement imperceptible to any eye—but it was proceeding, nevertheless, and without cessation. It was a journey which a rolling stone would make in a few seconds—the lofty point of departure was visible from the village below in the valley.
The prediction cut curiously close to the truth; forty-one years after the catastrophe, the remains were cast forth at the foot of the glacier.
