light engine

A light engine slid through the station, and he caught a glimpse of young Barton in the cab.

The light engine was to go on until it should "pick up" the delayed train between stations.

Get the hand bilge pump going and I'll start the power pump with the electric light engine!

Possibly also, a Railway Manager might agree to put a specially light engine to your train.

We were all of opinion that it was impossible to make a sufficiently light engine for the purpose.