Hi there Watty,
Don't forget that metric wire sizes have been used in the U.K. only since about 1970. House wiring cables prior to that were specified as number of strands and diameter (e.g. 7/.029 = 7 strands each .029" dia.), but we also have the British SWG (Standard Wire Gauge) which works in a similar way to AWG (e.g. 32 SWG is smaller than 28 SWG).
I have read an explanation of the derivation of SWG, but it was a long time ago and I can't remember the details now.
