[John Webb]

Railways in Britain have always been required to fence off their tracks, originally to stop cattle and other livestock straying from adjacent land, more recently to deter trespass, particularly by children onto electrified lines. The fencing also included gates at road crossings.

Therefore there has never been the need for a powerful light to warn of the approach of the train and the oil lamps were needed only for the information of signalmen and other trains.

With the widespread change to colour light signalling, automatic half-barrier road crossings and the more silent motive power of electric and diesel, it was realised that oil lamps were too weak to stand out, and in any case the higher speed of trains meant they would more often blow out. So lighting of greater brilliance has been built into locos and multiple units. Even preserved steam locos out on the main line now have to carry a battery-operated headlamp to improve the visibility of their approach both for track workers and trespassers.

Regards,
John Webb

 

[John Webb]

The "Handbook for Railway Steam Locomotive Enginemen" published by the British Transport Commission in 1957 and reprinted by Ian Allan in 1998 (ISBN 0 7110 0628 8) shows that the water gauges were set with their bottom connection at or just above the level of the highest part of the firebox crown, so to some degree this was indicated to British enginemen.
Some locos did have gauge glass lamps fitted. The above book refers to the need for enginemen to ensure they have on the engine "a complete set of lamps" - but it does not say if this included a hand lamp as well as the head and tail lamps required to be put on the engine.
By 1978 the BR Rule book also required every driver to carry a handlamp in working order - I assume that this would have been the battery-operated 'Bardic' torch. But with only diesel locos about with lit instruments by that time this must have been for inspecting things.

Regards,
John Webb