WEATHER (AS. urcder, 011G. Gen Wetter, weather; connected with OChurch Slay. redro, good weather, redrru, clear, bright, Skt.
to blow). The condition of the atmosphere at any time in respect of temperature, moisture, precipitation, sunshine, wind, electricity, dust, or any other meteorological element. The study of weather is of fundamental importance to man kind, and has always received great attention, especially because of the desire to anticipate or predict approaching important changes in the weather. The weather bureau (q.v..) or meteor ological office, aS now established in every civi lized nation of the globe, represents the latest practical application of physical science to the needs of mankind; its primary duty is to pre serve and study the records of local weather in order to make satisfactory local forecasts.
:Modern physical meteorology with its elaborate weather records may be said to have begun in 1653, when Ferdinand II., Grand Duke of Tus cany, distributed thermometers to several clois ters in Italy and organized a system of daily records under the general oversight of Father Luigi Antinori. in 1657 barometers, vanes, and hygrometers were added to the equip ment of these stations. Continuous automatic records of the individual features of the weather probably began in England between 1666 and 1670, with the :Moreland barometer and other apparatus devised by a special committee of the Royal Society, of which Sir Christopher Wren was chairman. A great advance has been made in meteorology since the 'great exhibition' or `World's Fair' of 1851 at London, when for the first time the items appropriate to the weather map were telegraphed for display upon charts.
At the present time similar daily weather maps are compiled by all nations so that the student quickly acquires a comprehensive view of the conditions existing in any part of the world. In 1873 the United States Weather Bureau, then a part of the Signal Service of the army, commenced the formation of daily weather map of the whole Northern ITemisphere, which was published continuously from 1S75 to 1883, inclusive, and was kept up in manuscript for ten years later. This gigantic undertaking included observations from the ocean as well as the land, and only by the use of similar maps can we hope to • understand and predict changes of the weather in distant parts of the globe. In order to make satisfactory predictions of the monsoon rains in India, a daily weather map of the Indian Ocean, or the monsoon area, was compiled at Calcutta during the years 1893-99, and by agreement be tween the Secretary of War and the Secretary of the Navy. daily weather maps of the Atlantic and Pacific oceans have been compiled by the United States Hydrographic Office since 1888. (See Page, Instructions to Voluntary Obscrrers of the Ilydrographie Office. Washington. 1901.) Similar maps for the North Atlantic for 1881-82 were published by the London :Meteorological Office.