Alcohol thermometer Duke of Tuscany, who in 1654 made sealed tubes partly filled with alcohol or urine, with a bulb and stem, depending on the expansion of a liquid, and independent of air pressure. Other sources, including the Encyclopædia Britannica, credit German scientist Daniel Gabriel Fahrenheit with inventing the alcohol thermometer in 1709. Fahrenheit was a skilled glassblower and his alcohol thermometer was the world's first reliable thermometer. Alcohol thermometer The alcohol thermometer or spirit thermometer is an alternative to the mercury-in-glass thermometer and has similar functions. Unlike the mercury-in-glass thermometer, the contents of an alcohol thermometer are less toxic and will
Mercury-in-glass thermometer to the bulb. As the temperature rises, the mercury is pushed up through the constriction by the force of expansion. When the temperature falls, the column of mercury breaks at the constriction and cannot return to the bulb, thus remaining stationary in the tube. The observer can then read the maximum temperature over the set period of time. To reset the thermometer it must be swung sharply. This design is used in the traditional type of medical thermometer. A maximum minimum thermometer, also known as Six's thermometer, is a thermometer which registers the maximum and minimum temperatures reached over a