Daniel and Anders

As an American traveling in Europe, a person will hear the temperature given in degrees Celsius, and a member of my family has the best mnemonic for remembering the conversion: double the number you're given, and then add thirty. 25 becomes 80, 19 becomes 68...since the actual conversion is to multiply the Celsius number by 9/5 (which is slightly smaller than doubling) and then adding 32 (slightly larger than 30) this technique is quite accurate for every day use.

The fraction 9/5, out of all fractions, is used since it's the reduced form of 180/100. Worked into this multiplicand is the basic difference between the Fahrenheit and Celsius scales. If you have a ruler in front of you and one end represents water freezing and the other represents water boiling, if you divide that ruler into 100 marks, you'll get degrees Celsius; divide it into 180 marks, you get degrees Fahrenheit. As Americans who use the Fahrenheit scale, we're used to 32 as the freezing point of water, and 212 as the boiling point of water, a difference of 180 degrees. This wasn't originally on purpose...

Until the seventeenth century cold, or rather "cold", was a scary entity that came about every year and lasted half of it, a life threatening obstacle, part of nature's wrath. Eventually Italian glassblowers got skilled enough to blow rather uniform tubes, and scientists began trying to construct devices that could reliably gauge temperature. One problem was the solution inside the gauge was such that when it expanded it needed lot's of room, so a "thermometer" as we'd call it could be many meters long, coiled up like a spring, quite beautiful and fragile, it would work but not be very practical.

Another problem was that there was no universally agreed upon system for actually gauging the measurements. Most thermometer makers would paint marks on their tubes denoting things people universally understood; ice melting/water freezing; candle wax melting; water boiling.

One man who was busy working with this was Daniel Gabriel Fahrenheit. His innovation was to use mercury, which was much denser than the other alcohol solutions being used, which shrank his gauge down to writing-instrument size. He made zero the point at which the solution of ammonium chloride melted, and made where the gauge would reach when his wife held it under her tongue, ie body temperature, 100. He noticed that ice melted/water froze around 32, and water boiled around 212. Daniel refined the system to fix those numbers, 32 and 212, which changed the body-temp to what we understand as 98.6.

His system spread all over the world mainly because it had practical sized gauges. In Sweden, using a mercury gauged thermometer, Anders Celsius devised a measuring system that was based on a 100-unit breakdown. He originally had 0 degrees the point at which water boiled, and 100 degrees as the point where water froze, and the scale heading off into cold depths that at the time were unbounded; the idea that an absolute bottom was quite radical (and came later).

After Anders death, which came quickly after his system was developed, Carl Linnaeus, the botanist who developed the still-used-today naming nomenclature for living things on earth--kingdom, phylum, class, order, family, genus, specie--ended the insanity and reversed Anders' scale, making zero the freezing point and 100 the boiling point.

The Celsius scale has been adopted my most countries around the world, while America, Belize and Jamaica still use the Fahrenheit scale. In Canada, they use the Celsius scale for television and books, but thermometers outdoors, mounted on walls, tend to have both written on them.

I think I prefer the Fahrenheit scale, but not because I grew up using it. I like the fact that one degree Fahrenheit is smaller than one degree Celsius, making more accurate whole degree measurements possible.