The metric faradiddle started here in
La Belle France 200-odd years ago. The French Revolutionaries wanted to get rid of everything associated with
l'ancien regime, so they changed everything possible, just to make sure it all couldn't come back!
They cut off the heads of the Royal family, the aristos, the landowners and anyone else vaguely bourgeoise they could catch, just to make sure.
They invented the guillotine for 'humanitarian reasons', [ although the increase in 'production' also came in handy, as it happens ].
Now don't start feeling sorry for the 'old regime'. They were as vindictive, cruel and blood-thirsty bunch as one could ever imagine. Nobody but the poor paid taxes.
Sébastien Paturel was one victim from my village. A farm laborer aged 19, in 1746 he walked to Mayenne for an evening out with 4 mates and was arrested as a 'salt -smuggler' under a new law designed to stamp out the practice. [ The tax on a £3 box of salt was £58! ]. Sentenced, though plainly innocent, to 5 years in the slave-galleys at Marseilles, he was welded into 28lbs of iron manacles and neck-weights and force marched 400-odd miles, but not before he had 'GAL' [galley-slave] burned into his forehead with a branding iron. He must have been one tough kid, because he survived. 5 years later he was cut out of his irons, had 'liberté' re-branded over the top of 'GAL' [!] and walked home. He married soon after. He died in 1790 aged 63. His descendants still live here.
So, where were we? Oh yes, they changed to cm, kg, metres and kilometers, litres and hectares.
At one point, they even decreed 10 hour clocks. 10 hour days each of 100 minutes each of 100 seconds. They invented the 'metric calendar'. 12 months of 30 days each divided into 3
decades per month, [ ie. 10-day 'weeks' ] with 5 or six additional days tacked on the year-end [ because they couldn't slow the earth down!
]. Year '1' was 1792 [First Republic], but Napolean abandoned it all 14 years later.
They bumped off a few of the brains too, like Lavoisier.
Then they all killed each other, just to make doubley sure!
Which was handy for Napolean Bonaparte.
Who, by the way had Scottish ancestors.
Actually, they did'nt change everything, not
quite.
Since pipe-threads were already standardised and all the plumbers had imperial threading tools, they kept the sizes the same but changed the nomenclature.
So, 1/2" BSP = 15mm x 21 and all metric pipe threads will fit imperial ones.
The pouce[inch], pied[foot], and livre[pound and also a £ sterling ] live on in common use by country folk. Heck the old boys round here still talk in
ancien Francs and they've been gone 40 odd years!
Alan