845: Long Hundred Apr 1, 2017

Not all cultures use a base-10 system for mathematics. Some peoples have used 20 as their base for counting, and some have used 12, which is not too hard to believe considering there are separate words for eleven and twelve before getting into the -teens, not to mention that there are twelve inches in a foot and twelve sections on a clock. While that same distinction for 'eleven' and 'twelve' exists in Romance languages, the Romans counted in base-10, as can be seen with Roman numerals, and the word 'digit'. Therefore, when they encountered northern Germanic tribes, they translated what is now 'hundred' as 'centum' (100) without taking into account that the Germanic 'hundred' was equivalent to 120. To avoid this confusion between these hundreds, people now use the term 'long hundred' for the Germanic one. Therefore, when the Icelandic historian, Snorri Sturluson wrote about the size of the peasant army that fought King Olaf II in AD 1030 as 'one hundred hundred', this would be 14,400 and not 10,000.

It should be noted that while a 'long hundred' equals 120, a UK 'long hundredweight' is equivalent to 112 lb avoirdupois.