2 points
Agreed. It sent me digging.
An avoirdupois pound is equal to 16 avoirdupois ounces and to exactly 7,000 grains. The conversion factor between the kilogram and the international pound was therefore chosen to be divisible by 7 with a terminating decimal representation, and an (international) grain is thus equal to exactly 64.79891 milligrams.
The Avoirdupois entry had a good visual representation as well as more weights history.
The “q. s.” remains a mystery though.
5 points
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The “q. s.” remains a mystery though.
q.s. means quantum satis and is Latin for “as much as necessary”. Which means they add enough for the right consistency or flavour or whatever, but the exact amount isn’t given and might vary.
2 points
