The Crap Shooter

[Sakura]

I also found the source of the rumour a bit later in the Wikipedia article:

"According to a German story, Fahrenheit actually chose the lowest air temperature measured in his hometown Danzig (Gdańsk, Poland) in winter 1708/09 as 0 °F, and only later had the need to be able to make this value reproducible using brine."

Guess it's just that: A German story

[oldwrench]

Personally, I think he just picked an arbitrary temperature and said that's zero, and another one for 100, but the coldest winter day and hottest summer day sounds as good as any. you could use the melting point of lead, or the boiling point of oil for that mater, but pure water is a good universal as long as you know the pressure to test at.

It's all relative!

[Sakura]

In 2019, the metric units were recalculated on the basis of natural constants. The reason for this was that the original kilogram had lost some 50 millionths of a gram in mass, although it has been under three glass bells in a safe in Paris since 1889. However this is possible...
Natural constants are valid always and everywhere. Moreover, they do not change.

[oldwrench]

Depends on which constant you use......... "the only thing constant is change".

[Sakura]

This may be truth for this strange sphere we call "earth"

By the way: If it changes it's not a constant by definition