Thomas Henderson graduated with distinction in the 1855 class at Bowdoin College.  During the next three years, he was the principal of an academy in Dover.  He studied law and finished the course at Harvard Law School in 1861.  He felt his duty was to his government, so he went to Norwich, Vermont, where he remained for several months under military instruction and drill.  In November, 1861, he accepted the position of adjutant of the Seventh New Hampshire Volunteers.   He was commissioned a major under the recommendation of Colonel Putnam upon the death of Major Smith in August, 1862.  In the assault on Fort Wagner, Major Henderson acted as the aide-de-camp to Colonel Putnam and upon the colonel's death, he was promoted to lieutenant-colonel.  He fought with the regiment at Olustee, Florida, and elicited high praise for his skill and gallantry at Drury's Bluff, Virginia.  At Deep Bottom, Virginia, he received a mortal wound to the hip and died within a few hours.  (pp. 467-469).