| On The Blockade
Oliver Optic | |
| On the Border with Andrew Jackson
John T. McIntyre | |
| On the Border with Crook
John Gregory Bourke | |
| On the Borderland
F. Britten Austin | |
| On the Brink of a Chasm: A record of plot and passion
L. T. Meade | |
| On the cattle plague: or, Contagious typhus in horned cattle. Its history, origin, description, and treatment
Honoré Bourguignon | |
| On the Choice of Books
Thomas Carlyle | |
| On the Church Steps
Sarah C. Hallowell | |
| On the Connexion of the Physical Sciences
Mary Somerville | |
| On the constitution of atoms and molecules
Niels Bohr |
