- 1864 to 18652,185
- 1866 to 18671,907
- 1868 to 18691,735
- 1870 to 18711,327
- 1872 to 18731,373
- 1874 to 18751,436
- 1876 to 18771,301
- 18781,122
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