The deep shaft below the Place of Knowledge had collapsed during the great tremor, burying the cavern below and the Cynosure within the cavern under an unimaginable burden of rock.

The shaft subsequently collapsed, and the excavation was again abandoned.

It had all seemed so sound, so permanent, yet one more quake and the whole shaft could easily collapse in upon itself.

The shafts have collapsed or have been filled in.

Since then half the shaft collapsed and now all that can be seen is half of a cylindrical shaft through the cliff at the corner of Sullivan and Elliot Streets.

Rescue crews managed to get about 300 feet underground before the shaft collapsed.

He'd been sitting in her hall for the better part of an hour, and she was as effectively trapped as a coal miner when the shaft collapsed.

Under Honduras, a subtrain shaft collapsed and eighteen hundred migratory agricultural workers were simultaneously cremated and dissolved in molten rock.

Last summer, the wooden shaft that drives the gristmill collapsed and broke, a victim of rot.

The "copper man" display, for example, shows the bones and tools of a Chilean copper miner who was killed when a shaft collapsed on him about 1,500 years ago.