In the 1860s, the area saw significant deterioration despite continuing improvements to Pennsylvania Avenue itself. Pennsylvania Avenue was lit with coal gas streetlights in 1851. The avenue was one of the few fully lit streets in the entire city of Washington. In July 1862, a horse-drawn trolley line was built along the street between the Capitol and White House. But despite these many improvements, much of the Pennsylvania Avenue Historic Site south of Pennsylvania Avenue had become a disreputable slum known as Murder Bay, the home to an extensive criminal underclass and numerous brothels. During the American Civil War, so many prostitutes took up residence in Murder Bay to serve the needs of General Joseph Hooker's Army of the Potomac that the area became known as "Hooker's Division." The two trapezoidal blocks sandwiched between Pennsylvania and Missouri Avenues (now the site of the National Gallery of Art) became home to such expensive brothels that it gained the nickname "Marble Alley." In the 1870s and 1880s, the avenue was the site of significant competition between horse-drawn streetcar and chariot companies. Pennsylvania Avenue saw its first electric streetlights give light on October 14, 1881. A small number of additional lights north of the avenue along 10th Street NW were lit later that month.