Meteorological instrumentation rain gauge. In 1714, Gabriel Fahrenheit creates 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 is demonstrated by Horace-Bénédict de Saussure. In 1806, Francis Beaufort introduced his system for classifying wind speeds. The April 1960 launch of the first successful weather satellite, TIROS-1, marked the beginning of the age where weather information became available globally. This was also used to measure the temperature of the surrounding air. A thermometer measures air temperature, or
Nationality Nationality Nationality is a legal relationship between an individual person and a state. Nationality affords the state jurisdiction over the person and affords the person the protection of the state. What these rights and duties are varies from state to state. By custom and international conventions, it is the right of each state to determine who its nationals are. Such determinations are part of nationality law. In some cases, determinations of nationality are also governed by public international law—for example, by treaties on statelessness and the European Convention on Nationality. Nationality differs technically and legally from citizenship, which is a