Mike Bristow wrote to uk.transport.london on Thu, 16 Dec 2004:

In article ,
Mrs Redboots wrote:
Also there are Class 313s at Clapham Jn (Silverlink metro trains at
Platform 2) - these are very similar to 315s, but can run on the third
rail as well as overhead power supply.

I think I knew that, but never actually noticed it! (I've been on those
trains occasionally).

The change power at a stop. When they go from 3rd rail to overhead,
you can just hear the "thunk" of the pan hitting the wires. I
/think/ the lights brighten just a little, too.

Yeah, that bit I knew - I've been on the 319s of Thameslink often
enough, and on Eurostar, too. But I hadn't realised the trains that I
occasionally catch between West Brompton & Clapham Junctions weren't the
usual Southern ones - and the Silverlink ones are so similar that I
never noticed *that*, either!
--
"Mrs Redboots"
http://www.amsmyth.demon.co.uk/
Website updated 12 December 2004