“Now,” said Captain Wopper emphatically, “that is a puzzler. How did it ever get up there?”
“I have read of such tables,” said Lawrence.
“They are the result of the sun’s action, I believe.”
“Oh, it’s all very well, Lawrence,” said Lewis, with a touch of sarcasm, “to talk in a vague way about the sun’s action, but it’s quite plain, even to an unphilosophical mind like mine, that the sun can’t lift a block of stone some tons in weight and clap it on the top of a pillar of ice about ten feet high.”
“Nevertheless the sun has done it,” returned Lawrence. “Am I not right Professor?”
The man of science, who had listened with a bland smile on his broad countenance, admitted that Lawrence was right.
“At first,” he said, “that big stone fell from the cliffs higher up the valley, and it has now been carried down thus far by the ice. During its progress the sun has been shining day by day and melting the surface of the ice all round, with the exception of that part which was covered by the rock. Thus the general level of the ice has been lowered and the protected portion left prominent with its protector on the top. The sides of the block of ice on which the rock has rested have also melted slowly, reducing it to the stalk or pillar which you now see. In time it will melt so much that the rock will slide off, fall on another part of the ice, which it will protect from the sun as before until another stem shall support it, and thus it will go on until it tumbles into a crevasse, reaches the under part of the glacier, perhaps there gets rolled and rounded into a boulder, and finally is discharged, many years hence, it may be, into the terminal moraine; or, perchance, it may get stranded on the sides of the valley among the débris or rubbish which we call the lateral moraine.”
As the party advanced, new, and, if possible; still more striking objects met the eye, while mysterious sounds struck the ear. Low grumbling noises and gurglings were heard underfoot, as if great boulders were dropping into buried lakes from the roofs of sub-glacial caverns, while, on the surface, the glacier was strewn here and there with débris which had fallen from steep parts of the mountains that rose beside them into the clouds. Sudden rushing sounds—as if of short-lived squalls, in the midst of which were crashes like the thunder of distant artillery—began now to attract attention, and a feeling of awe crept into the hearts of those of the party who were strangers to the ice-world. Sounds of unseen avalanches, muffled more or less according to distance, were mingled with what may be called the shots of the boulders, which fell almost every five minutes from the Aiguille Verte and other mountains, and there was something deeply impressive in the solemn echoes that followed each deep-toned growl, and were repeated until they died out in soft murmurs.
As the party crossed an ice-plain, whose surface was thickly strewn with the wreck of mountains, a sense of insecurity crept into the feelings of more than one member of it but not a word was said until a sudden and tremendous crash, followed by a continuous roar, was heard close at hand.
“An avalanche!” shouted Slingsby, pointing upwards, and turning back with the evident intention to fly.