Covered shaft | Article about covered shaft by The Free Dictionary
An interior enclosed space that extends through one or more stories of a building, connecting openings in successive floors, or the floors and roof; must be covered at the top.
References in periodicals archive
They were throwing small stones down a covered shaft
and listening for how long they took to hit the bottom.
Investigators believe Buras climbed to the chimney area and then stepped onto a covered shaft
In the immediate vicinity of the building are located on the property 2 with concrete covered Shafts
of the former coal mine.