Signal Service Corps ledgers, 1871-1900

Congress passed a resolution creating a national weather service on February 9, 1870, and it was soon signed into law by President Ulysses S. Grant. This new law directed the secretary of war to take meteorological observations and provide warnings of approaching storms. The Brevet Brigadier General Albert J. Mayer and his Signal Service Corps were assigned this duty on February 25, 1870 by the secretary of war. Weather observations began on November 1, 1870, Increase Lapham was the first forecaster of this group. Weather observations were taken three times each day (7:35 a.m., 4:35 p.m., and 11:35 p.m.) and were telegraphed to Washington, D.C. These reports consisted of barometric pressure and its change since the last report, temperature and its 24 hour fluctuation, relative humidity, wind velocity, pressure of the wind in pounds per square feet, amount of clouds, and the state of the weather. In June 1872, Congress extended the weather service beyond the Great Lakes, Gulf Coast, and Atlantic region to the rest of the country. Lieutenant H.H.C. Dunwoody organized state weather services in 1883. In October 1895, control of the State Weather Service was transferred to the United States Department of Agriculture Civilian Weather Bureau, which was formed in 1891.