Correspondence, orders, reports and returns of the Union authorities (embracing their correspondence with the Confederate officials) not relating specially to the subjects of the first and second series. It embraces the annual and special reports of the Secretary of war, of the General-in-Chief and of the chiefs of the several staff corps and departments; the calls for troops and the correspondence between the National and the several State authorities.
General index to the entire work (except for the Naval Records) with all appendix containing additions and corrections of errors discovered in the several volumes after their publication. It also includes "Special Compilations" containing (1) a synopsis of the contents of volumes; (2) a special index for the principal armies, army corps, military divisions and departments; and (3) a table showing volumes pertaining to contemporaneous operations.
The index refers the user to specific volumes. It is then necessary to consult the index at the back of the volume for pages etc.
The index has been included on each of the tabs for easy use.