Farenheit

Daniel Fahrenheit

Daniel Fahrenheit was born in the Polish city of Gdansk on the 14th of May 1686.

He was the oldest of five children and only fifteen when his parents both died. The city council put the four younger Fahrenheit children in foster homes. But Daniel Fahrenheit was instead to complete a four year apprenticeship in which he learnt about bookkeeping.

After his four years were over he turned to physics and became a glassblower and instrument maker.

In 1701, Fahrenheit spent ten years traveling round Europe, meeting scientists. This encouraged him to follow his interest in natural sciences and he began to study and experiment in that field. In 1724 this led him to Amsterdam where he lectured in chemistry and became a member of the Royal Society.It was there he learned about thermometers and because it was a trade in Amsterdam, Fahrenheit decided to stay, and make this his profession, so he borrowed against his inheritance to take up thermometer making.

When the city fathers of Gdansk found out, they arranged to have Fahrenheit arrested, so until he was the legal age of 24 he had to dodge police. At first he was simply on the run, but he decided to keep traveling through Denmark, Germany, Holland, Sweden and Poland.

Florentine thermometer scales varied no two were the same; makers marked the low point on the scale during the coldest day in Florence that year. They marked the high point during the hottest day. Fahrenheit wanted thermometers to be reproducible during the year and realized the trick wasn't using the coldness or hotness of a particular day or place, but finding materials that changed at certain temperatures.

For seven years Fahrenheit worked on an alcohol thermometer scale, based on three points. He chose the freezing point of a certain salt-water mixture for zero, he used the freezing point of water for 32 degrees and body temperature was 96 degrees.

Fahrenheit used alcohol for his first few thermometers but after several series of experiments substituted it for mercury because of its rate of expansion, although it is less than that of alcohol, it is more constant. He also found mercury could be used over a much wider temperature range than alcohol. These experiments also led to the discovery that the boiling point of water varied with changes in atmospheric pressure and the phenomenon of the super cooling of water (this means, cooling water