discontent increased in the days afterward when Lincoln put out a call for volunteers to serve 90 days and end the insurrection. New militia units from several Northern states were starting to transport themselves south, particularly to protect Washington, D.C., from the new Confederate threat in Virginia. Baltimore's newly elected reform mayor, George William Brown, and the new police marshal (chief), George Proctor Kane, anticipated trouble and began efforts to placate the city's population. On Thursday, April 18, 460 newly mustered Pennsylvania state militia volunteers (generally from the Pottsville, Pennsylvania area) arrived from the state capital at Harrisburg on the Northern Central Railway at its Bolton Street Station (off present-day North Howard Street — across the street from the present site of the Fifth Regiment Armory of the Maryland National Guard, built 1900). They were joined by several regiments of regular United States Army troops under John C. Pemberton (later the Confederate general and commander at the siege of Vicksburg, Mississippi, whose surrender in July 1863 resulted in the first split of the Confederacy) returning from duty on the western frontier. They split off from Howard Street in downtown Baltimore and marched east along the waterfront to Fort McHenry and reported for duty there. Seven hundred "National Volunteers" of Southern sympathizers rallied at the Washington Monument and traveled to the station to confront the combined units of troops, which unbeknownst to them were unarmed and had their weapons unloaded. Kane's newly organized city police force generally succeeded in ensuring the Pennsylvania militia troops' safe passage marching south on Howard Street to Camden Street Station of the Baltimore and Ohio Railroad. Nevertheless, stones and bricks were hurled (along with many insults) and Nicholas Biddle, a black servant traveling with the regiment, was hit on the head. But that night the Pennsylvania troops, later known as the "First Defenders", camped at the U.S. Capitol under the uncompleted dome, which was then under construction. April 19, 1861 On April 17, the 6th Massachusetts Militia departed from Boston, Massachusetts, arriving in New York the following morning and Philadelphia by nightfall. On April 19, the unit headed on to Baltimore, where they anticipated a slow transit through the city. Because of an ordinance preventing the construction of steam rail lines through the city, there was no direct rail connection between the Philadelphia, Wilmington and Baltimore Railroad's President Street Station and the Baltimore and Ohio Railroad's