Tuesday, 16 September 2014
Daniel Gabriel Fahrenheit was a German physicist, engineer, and glass blower who is best known for inventing the mercury-in-glass thermometer (1714), and for developing a temperature scale now named after him. Fahrenheit was born in 1686 in Danzig (Gdańsk), the Polish-Lithuanian Commonwealth, but lived most of his life in the Dutch Republic. The Fahrenheits were a German Hanse merchant family who had lived in several Hanseatic cities.
Thermometer consists of a bulb containing mercury attached to a glass tube of narrow diameter; the volume of mercury in the tube is much less than the volume in the bulb. The volume of mercury changes slightly with temperature; the small change in volume drives the narrow mercury column a relatively long way up the tube. The space above the mercury may be filled with nitrogen or it may be at less than atmospheric pressure, a partial vacuum. Read more...