It did not take a long time for me to determine what to do. At the risk of being crushed by the falling timbers and rock, I darted backward, extinguishing my light in the rapidity of my movements, and becoming wrapped in almost complete darkness. Luckily, however, there was a light burning in the level; and as I crept among the breaking timbers, it was as welcome to me as the polar star to a man at sea, when his compass has become unreliable. Another and another of the timbers gave way as I walked, or rather crept, beneath them. When they were broken in the centre, they had partly, but not completely, closed the passage, their ends being held firmly in the rock. I managed to reach the other side, and as soon as I considered myself safe, I turned round to see what was going on. The timbers settled very slowly; there was no one on the level beyond them; and had any persons been there, the settling of the roof was so slow, that they would have had plenty of time for escaping. When I reached the outside, I made a vow to avoid similar dangers in future, and it was some time before I again ventured where I should be liable to a similar accident. Falls of the roof are a kind of danger which is always thought of when underground works are considered. In certain kinds of rock there is no liability to occurrences of this sort. The roof is as solid, and as well supported, as that of any house, and there is no danger of its yielding; but where the rock is slippery and loose, or where the ground is soft, the peril that threatens is constant. Falls of earth are not unfrequent in digging wells. Many a man has lost his life in consequence. An exciting story is told of a well-digger, named Giraud, who was excavating a well near Lyons, about twenty years ago. [Sidenote: TERRIBLE FATE OF A WELL-DIGGER.] The earth caved in, and Giraud found himself dashed to the bottom of the hole by the side of a fellow-workman. Luckily, the timbers fell in such a way as to form a sort of arch above their heads, and thus saved them from being crushed at once. Some men, who were above at the time of the accident, immediately set to work to save the sufferers. It was necessary to dig a new shaft near the first, and then connect the two by a driftway, which would reach the men at the point where they were enclosed. Their efforts were constant, but in spite of them, a whole month was spent in reaching the spot, as fresh falls of earth were constantly occurring in the new workings. Giraud and his comrade could hear the noise of the pick, and could converse with the workmen, and assure them that they were alive.