- 1861 to 18642,851
- 1865 to 18692,600
- 1870 to 18741,931
- 1875 to 18791,776
- 1880 to 18841,781
- 1885 to 18892,454
- 1890 to 18943,208
- 18952,398
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