On 16 July, 06:57, 1501 wrote:
On 15 July, 23:07, CJB wrote:



*they were not exactly square but somewhat trapezoidal in
floor area.

Wasn't that to fit a pair of lift cars into a circular shaft?

Yes. Each lift had two separate power supplies, so if one failed the
other could be used. If there was some sort of mechanical or
electrical failure of the lift itself or its control system the other
lift in the same shaft could be manually stopped at the same level,
and the passengers transferred across from one car to the other; this
was a standard feature on these old Otis lifts. I don't know if it
was ever actually used, but presumably would have been done in
training. This would have been quicker than hand-winding the failed
lift, and could have been done even if the failed one was physically
jammed in some way. I had a copy of the instructions for hand-winding
these lifts somewhere; if I remember correctly it needed six people to
lift the two brakes and wind the two drums via two large wheels fitted
to the shafts. Not something to do if you could avoid it.