He and another were "spilling" along an old adit level, and at the point where they were working the sides were of decomposed granite and were weak. The level supports consisted of stull pieces hitched in the hanging and foot walls, and over these supports the piles were driven. The last stull piece, which was about 2 feet from the dirt, had been set with rather less pitch than usual and the bottom ledge of the hitch in the hanging wall was only half an inch deep. At the time of the accident Lanyon was cutting a hitch in the hanging wall for another stull piece when a big piece of ground, about 4 feet above him, fell from the hanging wall, knocked out the last stull piece and pinned him under it. The loose stone had been noticed at the commencement of the shift but it was thought that it would not fall. If legs had been set under the stull pieces, the accident would probably have been avoided