In article ,
Andrew Gabriel wrote:
In article ,
Mike Tomlinson writes:

Those mercury arc rectifiers in the background look interesting

There used to be lots of them in Underground stations.
Used to generate DC for powering lifts and things like that.

Cinemas and theatres too. For arc lights and projectors. Marvellous things.

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*If you must choose between two evils, pick the one you've never tried before

Dave Plowman London SW
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