Mercury-in-glass thermometer and public health by decreasing the amount of mercury waste released. The HPA had, in 2007, released a guide to dealing with small spills of mercury. In the United States, both the American Academy of Pediatrics and the United States Environmental Protection Agency recommend that alternative thermometers be used in the home. Mercury-in-glass thermometer The mercury-in-glass or mercury thermometer was invented by physicist Daniel Gabriel Fahrenheit in Amsterdam (1714). It 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.
Mercury-in-glass thermometer Nowadays, the triple point of water is used instead of the freezing point (the triple point occurs at 273.16 kelvins (K), 0.01 °C). Before the discovery of the true thermodynamic temperature, the thermometer "defined" the temperature; thermometers made with different materials would define different temperature scales (a coloured alcohol thermometer would give a slightly different reading than a mercury thermometer at, say half-scale). In practice, several materials gave very similar temperatures to each other and, when discovered, to the thermodynamic temperature. One special kind of mercury-in-glass thermometer, called a maximum thermometer, works by having a constriction in the neck close