- 1863 to 18642,235
- 1865 to 18692,631
- 1870 to 18741,942
- 1875 to 18791,784
- 1880 to 18841,794
- 1885 to 18892,465
- 1890 to 18943,235
- 1895 to 18993,280
- 1900 to 19043,309
- 19052,332
The preservation of the Duke University Libraries Digital Collections and the Duke Digital Repository programs are supported in part by the Lowell and Eileen Aptman Digital Preservation Fund