B&O runs the first electric locomotive in American railroading under Baltimore

Steam engines had always been a problem underground. When the Baltimore and Ohio Railroad completed the Howard Street tunnel beneath Baltimore in the early 1890s, smoke from its locomotives made the passage nearly impassable — a serious liability on the competitive New York–Washington corridor. In 1895, the B&O answered with something no American railroad had tried before: electric locomotives, running across 3.75 miles of the Baltimore Belt Line near Camden. The Royal Blue passenger service — already celebrated for its mahogany interiors, French-trained dining car chefs, and deep "Royal Saxony blue" livery — now glided silently under Baltimore's streets, pulled by a technology that would spend the next century reshaping American railroading…