A cornice is a mass of snow projecting over the edge of a precipice, and resting upon empty space. Occasionally it will bear the weight of one, or even several, men; but more often it gives way when trodden on, carrying a whole party to destruction. This was the case in the famous accident on the Lyskamm--a mountain where the cornices are particularly treacherous--when Messrs. William Arnold Lewis and Noel H. Paterson, with the guides Niklaus, Johann, and Peter Joseph Knubel, met their deaths in the year 1877. "The cornice," writes Mr. Hartley, who visited the scene of the accident immediately afterwards, "had broken away in two places, leaving some ten feet in the middle still adhering to the mountain. The length of the parts which broke away was, perhaps, forty feet on each side of the remaining portion. The distance of the fall we estimated at from twelve hundred to fifteen hundred feet. The bodies, from the nature of the injuries they had received, had evidently fallen upon their heads on the rocks, and then, in one great bound, had reached almost the spot where they were found." A typical instance of the ice-avalanche accident happened to, and has been recorded by, Mr. Whymper. Accompanied by A. W. Moore and the guides Croz and Almer, he was trying to discover a shorter route than those usually taken between Zinal and Zermatt. After spending the night in a _chalet_ on the Arpitetta Alp, they started, and struck directly up the centre of the Moming glacier. The route proved impracticable, and it became necessary to cut steps across an ice-slope immediately below the great pillars and buttresses of the ice-fall, which were liable to break away and descend upon them at any moment. "I am not ashamed to confess," wrote Mr. Moore in his journal, "that during the whole time we were crossing the slope my heart was in my mouth, and I never felt so relieved from such a load of care as when, after, I suppose, a passage of about twenty minutes, we got on to the rocks and were in safety. I have never heard a positive oath come from Almer's mouth, but the language in which he kept up a running commentary, more to himself than to me, as we went along, was stronger than I should have given him credit for using. His prominent feeling seemed to be one of indignation that we should be in such a position, and self-reproach at being a party to the proceeding; while the emphatic way in which, at intervals, he exclaimed, 'Quick; be quick,' sufficiently betokened his alarm." And now, let the rest of the story be told in Mr. Whymper's graphic words. Croz, it should be remembered, was leading, and had advised the perilous route.