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Philo of Byzantium is credited with the construction of the first thermoscope (or Philo thermometer), an early version of the thermometer. [6] It is also thought, but not certain, that Galileo Galilei discovered the specific principle on which the device is based and built the first thermoscope in 1593.
In the Galileo thermometer, the small glass bulbs are partly filled with different-colored liquids. The composition of these liquids is mainly water; some contain a tiny percent of alcohol, but that is not important for the functioning of the thermometer; they merely function as fixed weights, with their colors denoting given temperatures.
1701 — Ole Christensen Rømer made one of the first practical thermometers. As a temperature indicator it used red wine. As a temperature indicator it used red wine. ( Rømer scale ), The temperature scale used for his thermometer had 0 representing the temperature of a salt and ice mixture (at about 259 s).
A thermometer is simply a thermoscope with a scale. ... I propose to regard it as axiomatic that a “meter” must have a scale or something equivalent. ... If this is admitted, the problem of the invention of the thermometer becomes more straightforward; that of the invention of the thermoscope remains as obscure as ever.
The first devices used to measure weather phenomena were the rain gauge, the anemometer and the hygrometer. The 17th century saw the development of the barometer and the Galileo thermometer while the 18th century saw the development of the thermometer with the Fahrenheit and Celsius scales.
A Crookes radiometer in action. The radiometer is made from a glass bulb from which much of the air has been removed to form a partial vacuum.Inside the bulb, on a low-friction spindle, is a rotor with several (usually four) vertical lightweight vanes spaced equally around the axis.
RTD assemblies made from iron or copper are also used in some applications. Commercial platinum grades exhibit a temperature coefficient of resistance 0.00385/°C (0.385%/°C) (European Fundamental Interval). [7] The sensor is usually made to have a resistance of 100 Ω at 0 °C. This is defined in BS EN 60751:1996 (taken from IEC 60751:1995).
The first bolometers made by Langley consisted of two steel, platinum, or palladium foil strips covered with lampblack. [ 4 ] [ 5 ] One strip was shielded from radiation and one exposed to it. The strips formed two branches of a Wheatstone bridge which was fitted with a sensitive galvanometer and connected to a battery.