precise degree of Hallidie's involvement in the inception of the line, and to the exact date on which it first ran. According to the franchise granted by the city, operations were required to begin by August 1, 1873. A retrospective published in 1895 stated that a single car was run over the line at 4 AM on the morning of August 1 with few witnesses to ensure the franchise would not expire. Eppelsheimer would later bring a suit against Hallidie and the Clay Street Hill RR in June 1877 over patents, but dismissed it voluntarily the following March. Expansion The next cable car line to open was the Sutter Street Railway, which converted from horse operation in January 1877. This line introduced the side grip, and lever operation, both designed by Henry Casebolt and his assistant Asa Hovey, and patented by Casebolt. This idea came about because Casebolt did not want to pay Hallidie royalties of $50,000 a year for the use of his patent. The side grip allowed cable cars to cross at intersections. In 1878, Leland Stanford opened his California Street Cable Railroad (Cal Cable). This company's first line was on California Street, and is the oldest cable car line still in operation. In 1880, the Geary Street, Park & Ocean Railway began operation. The Presidio and Ferries Railway followed two years later, and was the first cable company to include curves on its routes. The curves were "let-go" curves, in which the car drops the cable and coasts around the curve on its own momentum. In 1883, the Market Street Cable Railway opened its first line. This company was controlled by the Southern Pacific Railroad and would grow to become San Francisco's largest cable car operator. At its peak, it operated five lines, all of which converged on Market Street to a common terminus at the Ferry Building. During rush hours, cars left that terminus every 15 seconds. In 1888, the Ferries and Cliff House Railway opened its initial two-line system. The Powell–Mason line is still operated on the same route today; their other route was the Powell–Washington–Jackson line, stretches of which are used by today's Powell–Hyde line. The Ferries & Cliff House Railway was also responsible for the building of a car barn and powerhouse at Washington and Mason, and this site is still in use today. In the same year, it also purchased the original