The Fahrenheit scale only preceded the Celsius scale by a few decades, and both were invented in the early 1700s.
Daniel Gabriel Fahrenheit, a German physicist, originally planned to place the 0 degree point at the temperature at which an equal water/salt mixture froze, the 30 degree point at where water froze and the 90 degree point at the temperature of the human body.
Unfortunately, he got those measurements wrong, and the freezing point of water was later revised to 32 degrees and the temperature of the human body to 98.6 degrees.
Swedish astronomer Anders Celsius‘s temperature scale originally placed the 0 degree point where water boiled, and the 100 degree point where water froze. This seems a bit absurd given today’s conventions, but there is a logic to it: In quotidian use we almost never deal with temperatures hotter than the boiling point of water, though we do deal with temperatures colder than the freezing point of water; it would make sense, therefore, to use the boiling point as a kind of natural origin, and measure out from there.
And if you’re a Swede inventing a new temperature scale, the idea of measuring a quantity of cold rather than a quantity of heat is not all that preposterous, certainly not if you’ve just recently been subjected to a Swedish winter.
Had Celsius’s system not been tampered with, 76 (orthodox) degrees celsius would today correspond to 76 degrees fahrenheit, and we’d all assign that temperature some magical “ideal” quality, seeing how the value would be naturally endorsed by both scales. CNN’s weather forecasts would use a special graphic to highlight 76-degree days.
Instead, in real life, both scales “endorse” -40 degrees. What happened? Sweden’s most famous scientist ever, Carl Linnaeus, was heavily into plants, and since these tend to die around where water freezes, he felt this point was a more natural zero point. So he switched the temperature points around soon after Celsius died, in 1744.
This proved to be a good idea, in the long run. The concept of a quantity of heat would prove far more useful, scientifically, than a quantity of cold, as it would later lead Lord Kelvin to the Second Law of Thermodynamics, the concept of absolute zero, and the necessity of a scale that used it as a zero point. Whence kelvins.
And you wrote these things down why? In case you forgot, at some ill-determined future point, what it was you learned today?
So that people who can’t read yet can read it later, if they want to?
No, that’s a lie. Because whenever I come across arbitrary norms being taken for granted, I like to take note?
Being a transatlantic type myself, I feel a special kind of inner peace whenever the mercury hits -40.
I wonder if people would feel more comfortable with negative numbers (and the arbitrariness of the number scale) if Celsius’ original 0 = boiling, 100 = freezing idea had caught on? I guess yes, but the counterintuitiveness of the idea would have kept it from ever being adopted.
So in Celsius’ original system, a winter day in Sweden might be 110 degrees, and a summer day in the Sahara 50 or 40 degrees? And the temperature of the surface of the sun (or something else hotter than the boiling point of water) would be
-50 or -100?
Yes, though the temperature at the surface of the sun would be more like -5500 (orthodox) degrees Celsius. This would no doubt instinctively feel hot if we were used to thinking “negative degrees = a severe lack of cold.”