thumb<unk>  The<unk>  or spirit<unk>  is an alternative to the mercury-in-glass<unk>  and has similar functions. Unlike the mercury-in-glass<unk> , the contents of an<unk>  are less toxic and will evaporate quickly. The ethanol version is the most widely used due to the low cost and relatively low hazard posed by the liquid in case of breakage. An organic liquid is contained in a glass bulb which is connected to a capillary of the same glass and the end is sealed with an expansion bulb. The space above the liquid is a mixture of nitrogen and the vapor of the liquid. For the working temperature range, the meniscus or interface between the liquid is within the capillary. With increasing temperature, the volume of liquid expands and the meniscus moves up the capillary. The position of the meniscus shows the temperature against an inscribed scale. The liquid used can be pure ethanol, toluene, kerosene or isoamyl acetate, depending on manufacturer and working temperature range. Since these are transparent, the liquid is made more visible by the addition of a red or blue dye. One half of the glass containing the capillary is usually enamelled white or yellow to give a background for reading the scale. The range of usefulness of the<unk>  is set by the boiling point of the liquid used. In the case of the ethanol-filled<unk> , the upper limit for measurement is 78 °C (172.4 °F), which makes it useful for measuring daytime, nighttime and body temperatures, although not for anything much hotter than these. Ethanol-filled<unk> s are used in preference to mercury for meteorological measurements of minimum temperatures and can be used down to −70 °C (−94 °F). The physical limitation of the ability of a<unk>  to measure low temperature is the freezing point of the liquid used. Ethanol freezes at -114.9 °C (-174.82 °F). If an<unk>  utilizes a combination of ethyl<unk> , toluene, and pentane, its lower temperature range may be extended to measure temperatures down to as low as −200 °C (−328 °F). However, the measurement temperature range c. −200 °C to 78 °C, is highly dependent upon the type of<unk>  used.
Alcohol thermometer
Carbon monoxide detector
Dolorimeter
Bristol stool scale
AutoAnalyzer
Sweat test
Thermoluminescent dosimeter
Gaseous detection device