Among the first regiments to reach the nation's capital at the outbreak of war, the 71st New York State Militia was ordered by Gen. Winfield Scott to guard the Washington Navy Yard, then joined expeditions down the Potomac River and fought Confederate shore batteries near Aquia Creek. In recognition of that service, Capt. John Dahlgren, U.S.N., gave the regiment a pair of 12-pounder boat howitzers, which the commander assigned to Company I under Cpt. Augustus V.H. Ellis, whose men drilled constantly with them. Designed by Dahlgren in 1849, the smoothbore guns were adaptable for amphibious operations, able to mount in the bow of a landing craft and then be transferred quickly to a field carriage for use ashore. As the Union army advanced toward Manassas Junction, Company I hauled the howitzers by hand about 30 miles from the Navy Yard, with each soldier carrying two rounds of ammunition, an extra 24 lbs. per man. The guns served effectively on Matthews Hill alongside the Rhode Island battery, but in the frenzied retreat that afternoon they were abandoned and captured near Cub Run. Along with the loss of the boat howitzers, the 71st NYSM suffered 62 casualties in the battle.
