The collection contains two rolls of microfilm covering in alphabetical order, correspondents P-Z who wrote to the United States Adjutant General in 1821. Roll 143 contains P-Sm, 1821, and roll 144 contains Sp-Z, 1821. Included in roll 144 is a consolidated file for Henry Whiting (1812-1821).

This collection of microfilm contains registers of letters received in the offices of the United States, Topographical Bureau concerning its surveying and construction work. In addition, the collection contains a pamphlet written by the National Archives to accompany this microcopy and describes the registers in detail.