On 17/02/2021 16:50, nightjar wrote:
On 17/02/2021 13:09, Steve Walker wrote:
On 17/02/2021 11:26, NY wrote:
"nightjar" wrote in message
...

I never had a feel for Fahrenheit. It didn't really matter to me as
a kid what the outside temperature was beyond whether I needed to
wrap up warm or not. It was only when I started science at school
that exact temperatures mattered and we used the cgs system for that.

Fahrenheit has to be the most hare-brained temperature scale ever
devised - apart from the one which used an inverse scale so a higher
temperature was a lower number. It seems very obvious that you devise
a temperature scale that is based on (and is easily compared with)
the properties of the most abundant liquid on Earth: water.

Neither are particularly sensible, as that the freezing and
particularly boiling points of water can vary considerably with
variations in pressure. Yes, I know that they are defined at Standard
Pressure, but that means that you also need an accurate means of
establishing the pressure.

Which had existed for a century when Celcius proposed his scale. He set
100 as the freezing point of water and zero as the boiling point at the
mean atmospheric pressure at sea level. The scale we know as Celcius
today is actually the reverse of his.


and The Kelvin scale is set as 0K to be the triple point of water where
it exists in 3 sates of matter (solid, liquid & gas) all at the same
time, which is about 0.4 °C IIRC.