Fans of archaic unit systems may find solace in the fact that astronomy
still stubbornly resists the onslaught of SI units. The CGS system is
still king in astronomy: ergs/cm^2/s is our preferred unit of flux (except
radio astronomers use the Jansky) and we also like such non-standard units
as the Angstrom for wavelengths, light years and parsecs of course for
distance, and arcseconds and arcminutes instead of radians for angular
measures. In the astronomy articles I've written for Wikipedia, though, I
think I've stuck with SI except for light years and parsecs.
As for what UK folk use, well, the packets might be marked in metric but
the amounts are still imperial. We buy milk in 568ml (pint) bottles, peas
in 455g (1lb) packets, that kind of thing.
Not sure that changing distances on road signs would be that difficult or
at all dangerous, it's just that being on an island we have no compelling
reason to conform to the continental standard - there would be no benefit
to be gained from a switch.
-----Original Message-----
From: Tony Sidaway [mailto:minorityreport@bluebottle.com]
In the UK this is only for "folk" uses such as pints of beer and road
signs. I believe all scientific and engineering ventures switched to SI
long ago, and nearly all commercial institutions (aforementioned pints of
beer excluded, for instance) are required to use metric measure although
they are also permitted to provide equivalent ounces, pounds, stones and
whatnot. They sell orange juice in liters, butter by the kilogram, cloth
by the meter. Liquor is sold in metric measure, so in a pub you get a
pint of beer but a 35 ml measure of brandy, and a 200ml glass of wine.
Road signs haven't switched because it would be very difficult and
dangerous as well as politically explosive.