And for thermometers, it seems that is precisely what Fahrenheit was
up to. Fahrenheit was playing around and playing around and finally
set ice water at 32, and body temperature at 96, so that there were
64 divisions between the two. That way, no matter where you are in
the world, you can re-generate his thermometer. You stick the
thermometer in ice water, and mark it there. Then you stick it
under your tounge, and mark it there. Then you get a string, and
fold it in half 6 times, and you have the 64 divisions between 32
and 96!


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. Then Fahrenheit took his wife's temperature and
called that 100, and it appears that she wasn't feeling so well that
day.

The mixing of systems sometimes is puzzling. It shows up in the
amounts of Tetraethyl Lead per gallon of avgas: 0.5 ml per gallon for
80, and 2.0 for 100LL. Metric per U.S.
Why would they do that?

Dan