Weird and wonderful

19th October 2007 at 01:00
Roman numerals are decimal for whole numbers but fractions are duodecimal, ie divided by 12. The Roman for one-twelfth is uncia, from which we get the English words inch and ounce. One uncia is indicated by a dot, and the letter S (semis) is used for half. Hence, two-thirds would be S dot dot (eight-twelfths).

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