Dear all,  Regarding Brian Finch's note about IBM computer peripherals
using wire brushes:  Brian suggested that they never wore out.  As an
ex-operator from the days of RAMAC and Hollerith cards I would slightly
modify that view.

Heavily used, high-speed devices such as card readers, sorters and
mark-sense reader/punches certainly developed problems with wire brushes.
Card wrecks of sufficient severity would result in bent and twisted wires
requiring replacement.  Slight displacement of individual strands could
sometimes cause havoc on a long sort over several columns.

Yes, the technology was pretty reliable, but error-free?  Definitely not.

Yours reminiscingly,

Roger Waring