"Charles Ellson" wrote in message
...
On Wed, 18 Jul 2012 18:44:56 +0100, Arthur Figgis
wrote:

On 18/07/2012 12:58, Mortimer wrote:

Wouldn't a diesel multiple unit (or a "steam multiple unit", if such
things existed)

http://www.brc-stockbook.co.uk/smu.htm

Not a multiple-unit, more a steam carriage with through control from
the far end of the semi-permanently attached trailers.

And therefore not actually changing much in terms of traction because it
doesn't dramatically increase the number of driven axles or distribute them
along the whole length of the train.