Mercury-in-glass thermometers have been considered the most accurate liquid-filled types.

In the past, the traditional thermometer was a mercury-in-glass thermometer.

Two mercury-in-glass thermometers are supplied, protected by tough plastic containers.

For example, above the boiling point of mercury, a mercury-in-glass thermometer is impracticable.

The alcohol thermometer is an alternative to the mercury-in-glass thermometer and has similar functions.

Temperature systems are primarily either electrical or mechanical, occasionally inseparable from the system which they control (as in the case of a mercury-in-glass thermometer).

A special kind of mercury-in-glass thermometer, called a maximum thermometer, works by having a constriction in the neck close to the bulb.

A mercury-in-glass thermometer, similarly, converts measured temperature into expansion and contraction of a liquid, which can be read on a calibrated glass tube.

Unlike the mercury-in-glass thermometer, the contents of an alcohol thermometer are less toxic and will evaporate away fairly quickly.

To avoid this, some weather services require that all mercury-in-glass thermometers be brought indoors when the temperature falls to -37 C (-34.6 F).

The mercury-in-glass thermometer was invented by Daniel Gabriel Fahrenheit in Amsterdam (1714).

Likewise, a standard mercury-in-glass thermometer must absorb some thermal energy to record a temperature, and therefore changes the temperature of the body which it is measuring.

(c. 1713) Daniel Gabriel Fahrenheit switches from using alcohol to mercury as the thermometric fluid in his thermometers, creating the first mercury-in-glass thermometer.

A familiar application of a dilatometer is the mercury-in-glass thermometer, in which the change in volume of the liquid column is read from a graduated scale.

The boiling point of mercury limits the mercury-in-glass thermometer to temperatures below 356 C, which is too low for many industrial applications such as pottery, glass making and metallurgy.

In contrast, the range of a typical mercury-in-glass thermometer is fixed, being set by the calibration marks etched on the glass or the marks on the printed scale.

An ASTM mercury-in-glass thermometer with traceable certification of accuracy (against NIST standards) was used to assess water bath temperatures.

At the 5, 10, and 20 cm levels, a check may be made by inserting a mercury-in-glass thermometer into the ground, at the same level near the suspected sensor and comparing readings.

For example, the length of a column of mercury, confined in a glass-walled capillary tube, is dependent largely on temperature, and is the basis of the very useful mercury-in-glass thermometer.

Mechanical registering thermometers hold either the highest or lowest temperature recorded, until manually re-set, e.g., by shaking down a mercury-in-glass thermometer, or until an even more extreme temperature is experienced.

The measurement of the surface air temperature is essentially the same now as it was then, using a mercury-in-glass thermometer, which can be calibrated accurately and used down to -39°C, the freezing point of mercury.

Alcohol thermometers, infrared thermometers, mercury-in-glass thermometers, recording thermometers, thermistors, and Six's thermometers are used in meteorology and climatology in various levels of the atmosphere and oceans.

Philippines By the Philippines Department of Health's Administrative Order 2008-0221, all mercury equipment from hospitals, including mercury-in-glass thermometers, will be phased out in the Philippines by September 28, 2010.

Medical thermometers such as mercury-in-glass thermometers, infrared thermometers, pill thermometers, and liquid crystal thermometers are used in health care settings to determine if individuals have a fever or are hypothermic.

These are safer than a mercury-in-glass thermometer, and may be advantageous in some patients, but do not always give an exact result,except the analytic liquid crystal thermometer which show the exact temperature between 35.5 to 40.5 Celsius.