"John Rowland" wrote in
:


The old light bulbs that they had (have?) in Routemasters had left hand
threads - this was to stop anyone pinching them to use them at home.


RM bulbs had a standard size bayonet coupling.

This applied to the saloon lights, the platform light, the cab light, and
even the 'hidden' inspection lamp socket in the cab (which had no switch
and was constantly live).

If you had a lazy conductor, he could put a sixpence under the platform
light bulb, then when it got dark and you put the lights on - pop goes the
fuse and you had to park up until the fitters came out to replace same.

IIRC, RT fuses were accesible, but RM fuses were behind a bolted plate.