books.google.com - In the 1850s, Baltimore's 170,000 residents had few options when it came to getting around town. Before the decade's end, however, the omnibus--an urban version of the stagecoach--emerged as Baltimore's first mass-transit vehicle. Horsecars followed, then cable cars, and ultimately electrically powered...http://books.google.com/books/about/Baltimore_s_Streetcars_and_Buses_Marylan.html?id=pU9xPrw5uekC&utm_source=gb-gplus-shareBaltimore's Streetcars and Buses, Maryland
