The History of the Thermometer

Before thermometers discovered, astronomers and physicists made great efforts to be able to create a tool that can measure the temperature. They know that temperature can make the substance expands. To that end, they use the substance as a benchmark measure of expansion in measuring temperature. But the discovery of the temperature gauges can not be easily created. The experts need to find the right agent, the right technique and the right scale is also to be able to measure it carefully. Later in 1593, Galileo Galilei tried to make measurements using a thermometer with expansion of air. Tool created by Galileo is then called termoskop. Although still relatively very simple, but this is a rough tool can measure the temperature.

Galileo Termoskop

Termoskop Galileo consists of glass balls of chicken eggs is associated with a closed length of pipe filled with water. In a number of the load suspended in the liquid. Generally, the load is attached to the sealed glass bulb containing a colored liquid for aesthetic effect. When the temperature changes, the density of the liquid in the cylinder also change which causes the ball to move glass raised or sunk to reach the position where the density is the same as the surrounding liquid or interrupted by other glass balls. When the density difference is very small glass balls and terurutkan such a way that the less dense is above and that terapat under, it can form a temperature scale.

Nobility in Florence Tuscany, Ferdinand II, creating a better thermometer. The air inside the glass bulb is replaced with wine or alkhohol. The second fixed point is the temperature at the coldest winter and summer temperatures are hottest. Since the discovery Amontons and Ferdinand, then many emerging proposal on the benchmark point. There are proposing the use of a single point of reference only, but some are proposing two benchmark points.

Gabriel Daniel Fahrenheit

After reading the history of science that tells Amotons discoveries about the boiling point of water is fixed then Gabriel Daniel Fahrenheit thermometer compelled to make in order to see the natural phenomenon in the field of temperature. Fahrenheit thermometer repeat the design and use of mercury as a substance empirically. In 1714, Fahrenheit has created a mercury thermometer. This is a really thermometer carefully and thoroughly. The scale on the thermometer is known as degrees Fahrenheit.

Later on, note the use of mercury in measuring devices temperature has several advantages over the use of water. Among them:

• Mercury temperature range is quite wide. Mercury freezes at -40 ° C and boils at 360 ° C.
• The transition metal elements silvery, so it can be easily seen as shiny.
• Mercury does not wet the capillary Diding on the thermometer so that the measurement is being conscientious.
• Mercury is quite a regular expansion of the temperature to the temperature.

In 1730, Rene Antoine de Reamur Ferchault constructing a new temperature scale known as scale Reamur. In his experiments he used a mixture of wine and water in comparison 4 and 1. In 1742 Swedish astronomer at the University of Upsala, Anders Celsius dividing the distance in between the freezing and boiling points of water into 100 parts. Even this scale is known to scale Celsius or centigrade scale. On the Celsius scale, 0  C is the point at which water freezes and 100  C is the point at which water boils. Scale is the most commonly used in the world.

In 1848, Scottish physicist, Lord Kelvin, menyataka importance of the phenomenon of temperature-volume relationship or the Law of Charles and Gay-Lussac. For example, when we studied the relation temperature volume at various pressures. At a specified pressure value, the plot of volume against temperature produces a straight line. By extending the line to zero volume, obtained at the intersection with the temperature axis value of -273.15 C. At other pressures, different straight line obtained from the plot between volume temperature, but also obtained zero temperatures at the same volume, namely -273.15 C. (Raymond Chang, 2005: 130)