The William B. Franklin letter book contains approximately 500 copies of letters that Franklin wrote while living in Washington, D.C., between November 21, 1857, and July 29, 1859. Several of the earliest letters concern his position as a superintending engineer for the construction of the customs house in Portland, Maine, including his approval for improvements, records of associated costs, and reports of payments he received from the Treasury Department. The majority of the letters pertain to Franklin's work as Army Secretary to the Lighthouse Board, discussing the establishment, protection, and maintenance of lighthouses, as well as related financial issues. Franklin often responded to inquiries about specific lighthouses and sometimes suggested improvements, occasionally accompanied by diagrams. He also discussed beacons, described the method of replacing lanterns (p. 269), and provided illustrated specifications for building a lantern room (pp. 491-494). The opening pages of the volume contain an index, in which Franklin noted the recipients and subjects of his letters.
William Buel Franklin was born in York, Pennsylvania, on February 27, 1823. His father, Walter S. Franklin, served as a clerk for the United States House of Representatives. Franklin entered the United States Military Academy at West Point at the age of 16 and graduated as the first-ranking cadet in the Class of 1843. Following his graduation, he served in the Corps of Topographical Engineers and served in Mexico under General John E. Wool during the Mexican War. He later moved to Washington, D.C., and became a civil engineer, working as a lighthouse inspector. In 1857, he became Army Secretary to the Lighthouse Board. Franklin served in the Union Army during the Civil War, participating in several battles under Major General George B. McClellan and attaining the rank of major general. He resigned his commission after the war, and continued to work as an engineer in Hartford, Connecticut, where he oversaw construction of the state capitol in the 1870s. William B. Franklin died on March 8, 1903.