In addition to the central forecast district at Washington, seven others are maintained, hav ing their centres at Chicago, Boston, Galveston, San Francisco, Portland, and Denver, each of which issues independent forecasts or local modifications of those issued from Wash ington. In the interests of local climatology, the larger States, or groups of smaller States, are organized as sections, and publish monthly a section report, which gives every observation of rainfall and temperature made during the inonth, as also charts of isotherms and rainfall. There are at present forty-five such sections, including those from Cuba and Porto Rico. The analogous publications for the Hawaiian Islands and for the Philippines are specially provided for by those territories. The general climatology of the United States is provided for by the publica tion of the Annual Report of the Chief of the Bureau. which contains several hundred quarto pages of tabular matter and additional special reports or memoirs. In order to secure prompt publication of general climatological data, the bureau publishes a Monthly Weather Review, which contains not only a summary rela tive to storms, forecasts and warnings, and the general climate and crop conditions, but also ten or twenty pages of special contributions and notes bearing on questions of meteorology.
All apparatus used by the bureau is carefully tested, and all stations are frequently inspected, so as to secure the greatest possible exactness and uniformity. The Instrument Division is in charge
of apparatus and methods of observation. New instruments and improvements on old apparatus emanate from this division, which has become especially famous for Professor Alarvin's work on anemometers, psychrometers, metcovographs, and the development of the Ilargrave kite for atmospheric exploration. When ordinary tele graph and telephone lines and cables are not otherwise available, the bureau builds and con trols its own lines. Special researches of any magnitude are generally published as bulletins, of which there are an octavo and a quarto series. Among these are those relating to international weather charts and storm tracks for the North ern Hemisphere; the results of observations with kites; and the study of the radiation of heat by the air. The headquarters of the Weather Bureau are located in a special building in Washington, D. C. The early history of this and other na tional weather bureans is given in Bulletin Yo. 11; many additional details will he found in Moore, Meteorology, Practical and Applied (Lon don. 189-I). See also Abbe, Aims and Methods of Slate Weather gerrices (Baltimore, 1900)': Bayard, Annual Presidential Address, before Royal Meteorological Society (London. January, Bartholomew, Physical Atlas, vol. iii., "Meteorology" (London, 1900), See SIGNALING