%528. The Boom Towns.%--A proclamation that a part of Oklahoma would be opened April 22, caused a wild rush from every part of the West, till five times as many settlers as could possibly obtain land were lined up on the borders waiting for the signal to cross. Precisely at noon on April 22, a bugle sounded, a wild yell answered, a cloud of dust filled the air, and an army of men on foot, on horseback, in wagons, rushed into the promised land. That morning Guthrie was a piece of prairie land. That night it was a city of 10,000 souls. Before the end of the year 60,000 people were in Oklahoma, building towns and cities of no mean character. Within fifteen years Oklahoma had a population of over half a million; and Congress provided (1906) for the admission, in 1907, of a new forty-sixth state, including both Oklahoma and what was left of the old Indian Territory. SUMMARY 1. One important result of the Civil War was a great industrial revolution. 2. Mining for precious metals, the Northern Pacific Railroad, and other causes led to the admission into the Union of Colorado (1876), North and South Dakota, Montana, Washington (1889), Idaho, Wyoming (1890), Utah (1896), and Oklahoma (1907). CHAPTER XXXIV MECHANICAL AND INDUSTRIAL PROGRESS %529. Mechanical Progress.%--The mechanical progress made by our countrymen since the war surpasses that of any previous period. In 1866 another cable was laid across the bed of the Atlantic Ocean, and worked successfully. Before 1876 the Gatling gun, dynamite, and the barbed-wire fence were introduced; the compressed-air rock drill, the typewriter, the Westinghouse air brake, the Janney car coupler, the cable-car system, the self-binding reaper and harvester, the cash carrier for stores, water gas, and the tin-can-making machine were invented, and Brush gave the world the first successful electric light. %530. Uses of Electricity.%--Till Brush invented his arc light and dynamo, the sole practical use made of electricity was in the field of telegraphy. But now in rapid succession came the many forms of electric lights and electric motors; the electric railway, the search light; photography by electric light; the welding of metals by electricity; the phonograph and the telephone. In the decade between 1876 and 1886 came also the hydraulic dredger, the gas engine, the enameling of sheet-iron ware for kitchen use, the bicycle, and the passenger elevator, which has transformed city life and dotted our great cities with buildings fifteen and twenty stories high. The decade 1886-1896 gave us the graphophone, the kinetoscope, the horseless carriage, the vestibuled train, the cash register, the perfected typewriter; the modern bicycle, which has deeply affected the life of the people; and a great development in photography.