
hat tip Geoff.
I did have a peek to see what the reason behind the Fahrenheit scale was in the first place…
The two key points used in deciding the numbering of the scale were the melting point of ice and normal human body temperature. Having already decided that 0F would be the temperature at which a mixture of ice, water, and ammonium chloride, a salt, at a 1:1:1 ratio coexisted*, Mr Fahrenheit manipulated the scale on his apparatus such that 32 came out to be the melting point of ice, and 96 the body temperature.
This meant there were 64 points between these marks – which, being a power of 2, could be drawn by a series of bisections. So the physical engineering of a scale based on the available technology in 1724 was what drove the decision, rather than easier mathematics for actual calculations.
*this is not too terrible a choice, as it’s a frigorific mixture, meaning it reaches an equilibrium temperature independent of the temperature of any of its component chemicals before they are mixed.