Is that true about fahrenheit? I’ve never heard that before.
Comment on Handy temperature conversion scale.
herescunty@lemmy.world 7 months ago
Three scientists arguing over the definition of zero
Celsius says “zero is the freezing point of water”
Fahrenheit says “no, zero is the freezing point of ammonium chloride”
Kelvin says “hold my beer”
Paradachshund@lemmy.today 7 months ago
fhqwgads@possumpat.io 7 months ago
If I remember correctly, it’s not the freezing point. Fahrenheit used a brine that included ammonium chloride to set 0 on his scale since it was the closest thing he could make in his lab that was a consistent temperature. The other end was body temperature, which he set at 96 if I’m remembering right since it’s more easily divisible than 100. He was a little off on his body temperature measurements so it’s considered a little higher than that now.
ricecake@sh.itjust.works 7 months ago
It’s more chaotic than that.
He started with the Romer scale (brine freezes at zero, water 7.5, boils at 60, body temperature 22.5), which he tweaked to not need fractions for plain water freezing and body temperature by fudging some numbers and multiplying by four.
This made water freeze at 30 and human body temperature 90. He recalibrated it so that it was 32 and 96 so that there were 64 degrees between them, so he could draw the markings by dividing the interval between them in half six times.
He then saw that water boiled at about 212 on this scale, so he tweaked it again so that water froze at 32 and boiled at 212, since they’re 180 degrees apart, which is desirable because it puts them on opposite sides of a temperature gauge.
Because of these tweaks, the original brine temperature is now about 4F, and body temperature is 98.6.
The tweaks make sense if you know that Fahrenheit was making and selling temperature gauges, so taking the Romer scale and marking every quarter degree gets you the first Fahrenheit scale.
Then he tweaked it to make it easier to produce, and then again to fit in the dial better.BallsandBayonets@lemmy.world 7 months ago
So he fudged the science so the product would be easier/cheaper to make? Why does this feel like such a common story?
Paraneoptera@sopuli.xyz 7 months ago
It’s debated. One source points to the lower end of the scale established as the freezing point of a brine made by dissolving ammonium chloride in water.
umbrella@lemmy.ml 7 months ago
Kelvin: Zero is the freezing point of the universe
SirQuackTheDuck@lemmy.world 7 months ago
Kelvin: Zero is the freezing point.
Scientists: Of what?
Kelvin: Yes.