| Type of library code | Type of library detailed |
|---|
| Acad | Academy library |
| Agri coll | Agricultural and mechanical college library |
| Agri socl | Agricultural social library |
| Agri state | Agricultural library belonging to a state gov. |
| Antiq socy | Antiquarian society library |
| Appren | Apprentices' library |
| Art coll | Art college library |
| Art mus | Art museum library |
| Art socy | Art society library |
| Asylum | Asylum library |
| Athen | Atheneum library |
| Bar | Bar association library |
| Book | Book club library |
| Bus coll | Business college library |
| Bus law | Business law library |
| Chamb | Chamber of commerce library |
| Church | Church library |
| Co edu | County education library |
| Co law | County law library |
| Co med | County medical library |
| Co sci | County scienctific library |
| Co theo | County theological library |
| Coll | College library |
| Coll socy | College student society library |
| Comm | Commercial circulating library |
| Convent | Convent library |
| Court | Court library |
| Del | Deleted Cards |
| Dentist | Dentistry library |
| Edu | Education library |
| Elem | Elementary school library |
| Eng socy | Engineering society library |
| Fire | Fire company library |
| For lang socy | Foreign language society library |
| Frat | Fraternal organization library |
| Garr | Garrison library |
| Germ socl | German social library |
| Germ socy | German society library |
| Gov | Government-aided social library |
| Health | Health, state board library |
| Hist socl | Historical social library |
| Hort socy | Horticultural society library |
| Hosp | Hospital library |
| Hotel | Hotel reading room |
| House | House of refuge library |
| HS | High school library |
| Indust | Industrial school for boys library |
| Juv socl | Juvenile social library |
| Ladies | Ladies |
| Ladies' socy | Ladies' society library |
| Law | Law library |
| Law coll | Law school library |
| Law socl | Social law library |
| Law state | State law library |
| Lib assoc | Library association |
| Lit socy | Literary society library |
| Local | Local government library |
| Lyceum | Lyceum library |
| Maclure | Maclure library |
| Manu | Manufacturers' (or mill) library |
| Mason | Masonic library |
| Mech | Mechanics' library |
| Med | Medical Library |
| Med coll | Medical college library |
| Med socl | Medical social library |
| Med socy | Medical society library |
| Merc | Mercantile library |
| Mil acad | Military academy library |
| Mil coll | Military college library |
| Mil socl | Military social library |
| Mill | Mills library |
| Mission | Mission library |
| Mission socy | Missionary society library |
| Music socy | Musical society library |
| Odd | Odd Fellows library |
| Pat | Patients' library |
| Pharm | Pharmacy library |
| PL owned | Public library owned by an individual |
| Prison | Prison library |
| Public | Public library |
| Read club | Reading club |
| Read room | Reading room |
| Reform | Reform school library |
| Rel | Religious library belonging to a town |
| Rel coll | Religious college society library |
| Rel hist socy | Religious historical society library |
| Rel socl | Religious social library |
| Rel socy | Religious society library |
| RR | Railroad library |
| School | School district library |
| Sci eng coll | Scientific or engineering college library |
| Sci eng socy | Scientific or engineering society library |
| Sci gov | Scientific library owned by a government |
| Sem | Seminary library |
| Socl | Social library |
| Socl-Strict | Socl-Strict |
| Socy | Society library |
| State | State library |
| Sun | Sunday school library |
| Temp | Temperance library |
| Terr | Territory library |
| Theo coll | Theological seminary library |
| Theo socy | Theological society library |
| Town | Township library |
| Trade | Board of trade library |
| US Gov | United States government library |
| Wn col | Women's college library |
| Wn lib | Women's library |
| Wn socy | Women's society library |
| Work men | Workingmen's library |
| YMA | Young Men's Assoc. library |
| YMCA | Young Men's Christian Association library |
| YMLA | Young Men's Library Association |
| Young Men's | Young Men's |
| YWCA | Young Women's Christian Association |