August 30 1862-June 6 1863Baltimore Maryland
The 138th was assigned to the Relay House which was part of the defense of Baltimore. At this time the 138th was integrated with the 8th Corps. The regiment guarded the Baltimore and Ohio Railroad from Southern sympathizers. Things stayed mostly the same through the winter of 1862 and the spring of 1863. On May 2nd 1863 Lieutenant Colonel M'Clennan was promoted to full colonel and assumed command after Sunwalts's command had been terminated on March 30th for insubordination. Three months later on June 6th the regiment was assigned to active duty and sent to Harper's Ferry.
The Relay House