This is the kind of bike that needs some gentle touching up to retain it's patina and to preserve and protect it for the next 68 years.

In the 40's a fixed / free set up would have been very common on most British bicycles as derailleur gears were not even commonplace in the 1950's... many bicycles were still being equipped with fixed wheelsets or internal gear hubs.

The wheel size could very well be 26 by 1 1/4 so the frame dimensions should be checked to see if it was built for an EA1 / S6 (597) clincher or the continental 700c / 622.