Talk:Quarter (unit)

Sigfig
Yes, it's possible to provide "exact" 10-decimal-place metric "equivalents", but these measures are from a time when such exactness was (a) physically impossible, based on the qualities of the scales being used, and (b) unrealizable, given that the English simply didn't usually enforce careful comparisons of the local standards with the nominal prototypes in London. Worse still, the "prototypes" were simply ignored: when the first examination in centuries was carried out on the London gallon prototypes in 1688, they found the grain/ale measures short by 10 cu. in. and no wine gallon whatsoever. All local standard wine gallons had been based off the Guildhall gallon, which was 7 cu. in. short. This prompted some shrugs until the booze merchants applied to be permitted to sell at the rate they were gauged (i.e., 224 cu. in. to the gallon) and Thomas Powis had to rule that 231 cu. in. was the custom regardless. Even then there wasn't a replacement of the standard until the 5th year of Queen Anne. Just leave 3 or 4-digit approximations as the highest level of accuracy actually practiced. — Llywelyn II   23:40, 19 April 2015 (UTC)