If one could cleave off the butt end of such a glacier--an oblong block two or three miles wide by five and a quarter long and two thousand feet thick-- he could completely hide the city of New York under it, and Trinity steeple would only stick up into it relatively as far as a shingle-nail would stick up into the bottom of a Saratoga trunk.
"The boulders from Mont Blanc, upon the plain below Ivrea, assure us that the glacier which transported them existed for a prodigious length of time. Their present distance from the cliffs from which they were derived is about 420,000 feet, and if we assume that they traveled at the rate of 400 feet per annum, their journey must have occupied them no less than 1,055 years! In all probability they did not travel so fast."
Glaciers are sometimes hurried out of their characteristic snail-pace. A marvelous spectacle is presented then. Mr. Whymper refers to a case which occurred in Iceland in 1721:
"It seems that in the neighborhood of the mountain Kotlugja, large bodies of water formed underneath, or within the glaciers (either on account of the interior heat of the earth, or from other causes), and at length acquired irresistible power, tore the glaciers from their mooring on the land, and swept them over every obstacle into the sea. Prodigious masses of ice were thus borne for a distance of about ten miles over land in the space of a few hours; and their bulk was so enormous that they covered the sea for seven miles from the shore, and remained aground in six hundred feet of water! The denudation of the land was upon a grand scale. All superficial accumulations were swept away, and the bedrock was exposed. It was described, in graphic language, how all irregularities and depressions were obliterated, and a smooth surface of several miles' area laid bare, and that this area had the appearance of having been PLANED BY A PLANE."
The account translated from the Icelandic says that the mountainlike ruins of this majestic glacier so covered the sea that as far as the eye could reach no open water was discoverable, even from the highest peaks. A monster wall or barrier of ice was built across a considerable stretch of land, too, by this strange irruption:
"One can form some idea of the altitude of this barrier of ice when it is mentioned that from Hofdabrekka farm, which lies high up on a fjeld, one could not see Hjorleifshofdi opposite, which is a fell six hundred and forty feet in height; but in order to do so had to clamber up a mountain slope east of Hofdabrekka twelve hundred feet high."
These things will help the reader to understand why it is that a man who keeps company with glaciers comes to feel tolerably insignificant by and by. The Alps and the glaciers together are able to take every bit of conceit out of a man and reduce his self-importance to zero if he will only remain within the influence of their sublime presence long enough to give it a fair and reasonable chance to do its work.
The Alpine glaciers move--that is granted, now, by everybody. But there was a time when people scoffed at the idea; they said you might as well expect leagues of solid rock to crawl along the ground as expect leagues of ice to do it. But proof after proof as furnished, and the 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 crevices 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 crevice and suspended him until help came.