The Federals built gun emplacements on Maryland Heights. The 30-Pounder Battery, also known as the Six-Gun Battery, was dug in October, 1862. Its fire covered the tops of Loudoun Heights and Bolivar Heights. The work had four sides but was open to the rear. And a 100-Pounder Battery was located on the crest of Maryland Heights between the Stone Fort and the 30-Pounder Battery. --Earl Hess