Descriptive Catalogue if the Government Publications of the United States, September 5, 1774-March 4, 1881 - first comprehensive bibliography for government publications not published until 1885. Under the leadership of Benjamin Poore.
Comprehensive Index to the Publications of the United States Government, 1881-1893 - John Griffith Ames is responsible for this publication that arranges materials alphabetically and includes an index.
The Monthly Catalog of the United States Government Publications was the most comprehensive index to materials from the 20th Century. The Monthly Catalog was first issed in 1885 and was unchanged until 1976 when the Government Printing Office (GPO) began following modern library practices using LC Subject headingsm following cataloging rules and producing MARC records.
Two cumulative indexes, the Cumulative Subject Index to the Monthly Catalog of United States Government Publications, 1900-1971 and the Cumulative Title Index to U.S. Government Publicatins, 1789-1976 are essential sets to locating documents prior to 1976.