Clay Street Hill Railway, which it incorporated into a new Sacramento–Clay line in 1892. In 1889, the Omnibus Railroad and Cable Company became the last new cable car operator in San Francisco. The following year the California Street Cable Railroad opened two new lines, these being the last entirely new cable car lines built in the city. One of them was the O'Farrell–Jones–Hyde line, the Hyde section of which still remains in operation as part of the current Powell–Hyde line. In all, twenty-three lines were established between 1873 and 1890. Evolution of motive power Originally, the cables were powered by stationary steam engines. For its initial three cables, the Ferries & Cliff House Railway constructed a three-story structure to house two coal-burning steam engines. The building was complete with a smokestack to vent away the heavy black smoke created by the Welsh anthracite coal that the company burned. Expansion of service required two additional coal-fired steam engines in 1890. Coal consumption in 1893 was about 10 tons per day. The system was converted from coal to oil burning in 1901, and the lessened amount of smoke allowed the smokestack to be shortened to . This shortened smokestack still stands at Washington-Mason car barn today. Electric energy was introduced in 1912, when a General Electric motor came online. By 1926, all steam operation of the cable ended when a second electric drive was installed, a General Electric motor. With the reduction in the number of cable car lines, the single 750-horsepower electric motor was eventually able to take over the job of running all of the lines. The limitation with that configuration was that if one cable car on one line broke down, all lines had to be stopped. Consequently, during the 1984 reconstruction, each of the four cables (California, Hyde, Mason and Powell) was separately powered by its own electric motor. Decline The first electric streetcars in San Francisco began operation in 1892 under the auspices of the San Francisco and San Mateo Electric Railway. By the beginning of 1906 many of San Francisco's remaining cable cars were under the control of the United Railroads of San Francisco (URR), although Cal Cable and the Geary Street Company remained independent. URR was pressing to convert many of its cable lines to overhead electric traction, but this was met with resistance from opponents who objected to what they saw as ugly overhead