Meteorology known as the first "anemometer". In 1607, Galileo Galilei constructed a thermoscope. In 1611, Johannes Kepler wrote the first scientific treatise on snow crystals: "Strena Seu de Nive Sexangula (A New Year's Gift of Hexagonal Snow)". In 1643, Evangelista Torricelli invented the mercury barometer. In 1662, Sir Christopher Wren invented the mechanical, self-emptying, tipping bucket rain gauge. In 1714, Gabriel Fahrenheit created a reliable scale for measuring temperature with a mercury-type thermometer. In 1742, Anders Celsius, a Swedish astronomer, proposed the "centigrade" temperature scale, the predecessor of the current Celsius scale. In 1783, the first hair hygrometer was demonstrated by
Medical thermometer Medical thermometer A medical thermometer (also called clinical thermometer) is used for measuring human or animal body temperature. The tip of the thermometer is inserted into the mouth under the tongue ("oral" or "sub-lingual temperature"), under the armpit ("axillary temperature"), or into the rectum via the anus ("rectal temperature"). The medical thermometer began as an instrument more appropriately called a water thermoscope, constructed by Galileo Galilei circa 1592–1593. It lacked an accurate scale with which to measure temperature and could be affected by changes in atmospheric pressure. Italian physician Santorio Santorio is the first known individual to have put a