The way I was taught: Fahrenheit sent his new thermometer with an
assistant to the far north to find the coldest temperature and mark the
thermometer at zero. Appears that the fella didn't try too hard,
perhaps not enjoying the cold, or else global warming was having an
up-cycle at that time.


Different stories around, see http://en.wikipedia.org/wiki/Fahrenheit. I
was taught the "lowest in Danzig" variant.

--
Thomas Borchert (EDDH)