On the Great Western Railway (and possibly other British lines) the coach with the controls for the locomotive for the "push-pull" arrangements that looker refers to were called "Autocoaches." The loco was on the front of the train going in one direction and at the rear of the train, controlled from the remote driving station at the end of the autocoach, when going the other way. This meant that the train could run both ways without having to have a run-around track at the terminal.
https://en.wikipedia.org/wiki/GWR_Autocoach
Apologies if I have any of the terminology wrong. I am a keen devotee of God's Wonderful Railway, but being a United Statesian, I don't have an instinctive feel for the British nomenclature.
Don