- On the Relations of Man to the Lower AnimalsAuthor: Thomas Henry HuxleyLanguage: English
- On the Ruin of BritainAuthor: Gildas, J. A. (John Allen) GilesLanguage: English
- On the Seashore: Cassell's "Eyes and No Eyes" Series, Book VIIAuthor: Smith, R. CadwalladerLanguage: English
- On the Significance of Science and ArtAuthor: Tolstoy, Leo, graf, Isabel Florence HapgoodLanguage: English
- On the Spanish Main; Or, Some English forays on the Isthmus of DarienAuthor: John MasefieldLanguage: English
- On the StairsAuthor: Henry Blake FullerLanguage: English
- On the Study of WordsAuthor: Richard Chenevix TrenchLanguage: English
- On the Study of ZoologyAuthor: Thomas Henry HuxleyLanguage: English
- On the SublimeAuthor: Longinus, active 1st century, Andrew Lang, Havell, H. L. (Herbert Lord), -Language: English
- On the TrackAuthor: Henry LawsonLanguage: English
- On the Trail of Grant and LeeAuthor: Frederick Trevor HillLanguage: English
- On the Trail of Pontiac; Or, The Pioneer Boys of the OhioAuthor: Edward StratemeyerLanguage: English
- On the Trail of the Space PiratesAuthor: Rockwell, Carey, Willy Ley, Glanzman, Louis [Illustrator]Language: English
- On the Trail: An Outdoor Book for GirlsAuthor: Lina Beard, Adelia B. (Adelia Belle) BeardLanguage: English
- On the Tree TopAuthor: Clara Doty Bates, Curtis, Jessie [Illustrator], Frank T. MerrillLanguage: English
- On the Vice of Novel Reading.: Being a brief in appeal, pointing out errors of the lower tribunal.Author: Young Ewing AllisonLanguage: English
- On WarAuthor: Carl von Clausewitz, Graham, J. J. (James John) [Translator]Language: English
- On With TorchyAuthor: Sewell Ford, Lincoln, F. Foster (Frederic Foster) [Illustrator]Language: English
- Once a weekAuthor: A. A. (Alan Alexander) MilneLanguage: English
- Once Aboard the Lugger-- The History of George and his MaryAuthor: A. S. M. (Arthur Stuart-Menteth) HutchinsonLanguage: English
- Once Upon A TimeAuthor: Richard Harding DavisLanguage: English
- Once Upon a Time in ConnecticutAuthor: Newton, Caroline Clifford, -Language: English
- Onder de wilde stammen op de grenzen van Afghanistan: De Aarde en haar Volken, 1917Author: T. L. (Theodore Leighton) PennellLanguage: Dutch
- Onder den rook der mijn: Eene novelle uit LimburgAuthor: Felix RuttenLanguage: Dutch
- Onder Moeders VleugelsAuthor: Louisa May Alcott, G. W. (Gerardina Wilhelmina) ElbertsLanguage: Dutch
- Onderweg in Tunis: De Aarde en haar Volken, 1909Author: Bellonie ChantreLanguage: Dutch
- One BasketAuthor: Edna FerberLanguage: English
- One Common FaithAuthor: Bahá'í International CommunityLanguage: English
- One Day: A sequel to 'Three Weeks'Author: Elinor GlynLanguage: English
- One Day At ArleAuthor: Frances Hodgson BurnettLanguage: English
- One Day More: A Play In One ActAuthor: Joseph ConradLanguage: English
- One Day's Courtship, and The Heralds of FameAuthor: Robert BarrLanguage: English
- One Hundred Best Books: With Commentary and an Essay on Books and ReadingAuthor: John Cowper PowysLanguage: English
- One Hundred Merrie And Delightsome Stories: Right Pleasaunte To Relate In All Goodly Companie By Way Of Joyance And JollityAuthor: Robert B. (Robert Bruce) Douglas, La Sale, Antoine de, Léon LebèqueLanguage: English
- One Man in His TimeAuthor: Ellen Anderson Gholson GlasgowLanguage: English
- One Man's Initiation—1917Author: John Dos PassosLanguage: English
- One of Life's SlavesAuthor: Jonas Lie, Muir, Jessie [Translator]Language: English
- One of Our Conquerors — CompleteAuthor: George MeredithLanguage: English
- One of Our Conquerors — Volume 1Author: George MeredithLanguage: English
- One of Our Conquerors — Volume 2Author: George MeredithLanguage: English
- One of Our Conquerors — Volume 3Author: George MeredithLanguage: English
- One of Our Conquerors — Volume 4Author: George MeredithLanguage: English
- One of Our Conquerors — Volume 5Author: George MeredithLanguage: English
- One of OursAuthor: Willa CatherLanguage: English
- One of the 28th: A Tale of WaterlooAuthor: G. A. (George Alfred) HentyLanguage: English
- One Third OffAuthor: Irvin S. (Irvin Shrewsbury) Cobb, Tony SargLanguage: English
- One Thousand and One Initial LettersAuthor: Owen JonesLanguage: English
- One Thousand Questions in California Agriculture AnsweredAuthor: Edward J. (Edward James) WicksonLanguage: English
- One Woman's LifeAuthor: Robert HerrickLanguage: English
- One Wonderful Night: A Romance of New YorkAuthor: Louis TracyLanguage: English
- One young manAuthor: J. E. (John Ernest) Hodder-WilliamsLanguage: English
- One-ShotAuthor: James Blish, H. R. Van DongenLanguage: English
- Only an IncidentAuthor: Grace Denio LitchfieldLanguage: English
- Only an Irish Boy; Or, Andy Burke's FortunesAuthor: Alger, Horatio, Jr.Language: English
- Onnen orjaAuthor: Eino LeinoLanguage: Finnish
- Ons Heerlijk Vaderland (deel 2 van 4): Boven en beneden den MoerdijkAuthor: Hendrik BlinkLanguage: Dutch
- Ons Vaderland van de vroegste tijden tot de 15de eeuwAuthor: M. Lievevrouw-CoopmanLanguage: Dutch
- Ontario Normal School Manuals: Science of EducationAuthor: Ontario. Department of EducationLanguage: English
- Ontario Teachers' Manuals: HistoryAuthor: Ontario. Department of EducationLanguage: English
- Ontario Teachers' Manuals: Household ManagementAuthor: Ontario. Department of EducationLanguage: English