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
Celsius (crater) Celsius with Celsius A. The interior floor of Celsius is almost featureless, except for a small craterlet in the northern half. By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Celsius. Celsius (crater) Celsius is a small lunar impact crater that is located in the rugged terrain in the southern hemisphere on the Moon's near side, it is named after Anders Celsius who was the founder of the Celsius temperature system which is part of the Metric system. It lies less than one crater diameter