Have you ever wondered why the Fahrenheit temperature scale seems so arbitrary? After all, the Celsius (centigrade) scale was designed to have 0 degrees for freezing water and 100 degrees for boiling water. How did the German physicist Gabriel Daniel Fahrenheit settle on using 32 degrees for freezing water and 212 degrees for boiling water?

Actually, Fahrenheit was not attempting to measure freezing or boiling water at all. Fahrenheit designed a thermometer so that it would be most useful in applications for the human body. He used an equal ice-salt mixture for 0 degrees F and 100 F was to represent normal body temperature. Eventually, scientists realized that Fahrenheit miscalculated slightly, so normal body temperature was "down-scaled" to 98.6 F.

Information for this item was taken from "Why Do Clocks Run Clockwise? and other Imponderables" by David Feldman, Harper & Row, Publishers, Inc. 1987.

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