1. O'Brien, Edward J. (Edward Joseph Harrington), 1890-1941 [Editor] - The Best Short Stories of 1921 and the Yearbook of the American Short Story
2. O'Brien, Edward J. (Edward Joseph Harrington), 1890-1941 [Translator]
   • Among the Millet and Other Poems
   • Bred in the Bone
   • Dirty Work Deep Waters, Part 11.
   • Little Folks Astray
   • Scott's Last Expedition Volume I
   • The Inferno
3. O'Brien, George - An Essay on Mediaeval Economic Teaching
4. O'Brien, Jack - Into the Jaws of Death
5. O'Brien, Seumas - Duty, and other Irish Comedies
6. O'Conner, T. P. - Sketches in the House (1893)
7. O'Cotter, Pat - Rhymes of a Roughneck
8. O'Donnell, Elliott, 1872-1965
   • Animal Ghosts Or, Animal Hauntings and the Hereafter
   • Scottish Ghost Stories
   • The Sorcery Club
9. O'Grady, Standish, 1846-1928
   • Early Bardic Literature, Ireland.
   • The Coming of Cuculain
10. O'Leary, James [Editor]
    • Bolougne-Sur-Mer St. Patrick's Native Town
    • The Most Ancient Lives of Saint Patrick Including the Life by Jocelin, Hitherto Unpublished in America, and His Extant Writings
11. O'Meara, James, 1825-1903 - The Vigilance Committee of 1856
12. O'Neill, Elizabeth (Elizabeth Speakman), 1877- - Stories That Words Tell Us
13. O'Neill, Eugene, 1888-1953
    • Anna Christie
    • The First Man
    • The Hairy Ape
14. O'Reilly, A. J. (Augustine J.) - Alvira, the Heroine of Vesuvius
15. O'Rourke, John - With Notices of Earlier Irish Famines
16. O'Sullivan, Vincent [Translator]
    • A Dish of Orts : Chiefly Papers on the Imagination, and on Shakespeare
    • A Rough Shaking
    • A Select Party
    • Authors and Friends
    • — Volume 01
    • From Boyhood to Manhood Life of Benjamin Franklin
    • Gloria and Treeless Street
    • Marjorie's New Friend
    • Saint Augustin
    • Slavery Ordained of God
    • The Greater Inclination
    • The Last Hope
    • The Leopard Woman
    • Youth: Its Education, Regimen, and Hygiene
17. O. G. C. [Translator]
    • Cad Metti, The Female Detective Strategist Dudie Dunne Again in the Field
    • Cluthe's Advice to the Ruptured
    • Slave Narratives: A Folk History of Slavery in the United States From Interviews with Former Slaves Tennessee Narratives
    • Sunset Pass or Running the Gauntlet Through Apache Land
    • The Boy Ranchers Among the Indians or, Trailing the Yaquis
    • The Continental Monthly, Vol. 2, No. 2, August, 1862 Devoted to Literature and National Policy
    • The Reckoning A Play in One Act
18. Ober, C. K. - Out of the Fog
19. Ober, Frederick A. - Amerigo Vespucci
20. Ober, Frederick Albion, 1849-1913 - The Patriot
21. Obrien, Francis P. - The High School Failures A Study of the School Records of Pupils Failing in Academic or Commercial High School Subjects
22. Oemler, Marie Conway, 1879-1932
    • A Woman Named Smith
    • Slippy McGee, Sometimes Known as the Butterfly Man
    • The Purple Heights
23. Ogden, Ruth, 1853-1927 - Tattine
24. Ogg, Frederic Austin, 1878-1951
    • The Old Northwest : A chronicle of the Ohio Valley and beyond
    • The Reign of Andrew Jackson
25. Ogilvie, David Douglas - F. Yeo.) Battn. R.H. 1914-1919
26. Ogilvy, Maud - Marie Gourdon A Romance of the Lower St. Lawrence
27. Ohnet, Georges, 1848-1918
    • — Complete
    • — Volume 01
    • — Volume 02
    • — Volume 03
    • — Volume 04
28. Okakura, Kakuzo, 1863-1913 - The Book of Tea
29. Olcott, Frances Jenkins, 1872-1963 - Good Stories for Holidays
30. Olesch, Gunther [Translator]
    • Action Front
    • — Volume 2
    • Boy Scouts in Mexico; or on Guard with Uncle Sam
    • Henry VI Part 1
    • Henry VIII
    • History of John Bull
    • King Arthur's Socks and Other Village Plays
    • Life on the Mississippi, Part 10.
    • My Life and My Efforts
    • On Compromise
    • On Something
    • Richard III
    • Rosamund, queen of the Lombards, a tragedy
    • The Adventures of Hugh Trevor
    • The Brook Kerith A Syrian story
    • The Cruise of the Kawa
    • The Naturalist in Nicaragua
    • The Nile tributaries of Abyssinia, and the sword hunters of the Hamran arabs
    • Volume 5, part 3: Franklin Pierce
31. Oliphant, Laurence, 1829-1888
    • A Journey to Katmandu (the Capital of Napaul), with The Camp of Jung Bahadoor; including A Sketch of the Nepaulese Ambassador at Home
32. Oliphant, Mrs. (Margaret), 1828-1897
    • A Little Pilgrim Stories of the Seen and the Unseen
    • Being a Narrative of Certain Recent Events in the City of Semur, in the Department of the Haute Bourgogne. A Story of the Seen and the Unseen
    • In the Unseen
    • Jeanne D'Arc: her life and death
    • Old Lady Mary A Story of the Seen and the Unseen
    • The Little Pilgrim: Further Experiences. Stories of the Seen and the Unseen.
    • The Open Door, and the Portrait. Stories of the Seen and the Unseen.
33. Oliver, Charles A. (Charles Alexander), 1858-1932 - ABC's of Science
34. Oliver, Stephen, 1950-
    • Deadly Pollen
    • Unmanned
35. Ollivant, Alfred, 1874-1927
    • A Romance of the Sea
    • Bob, Son of Battle
36. Olmsted, Everett Ward, 1869- [Editor]
    • Autobiography
    • — Volume 42, No. 07, July 1888
    • Choice Specimens of American Literature, and Literary Reader Being Selections from the Chief American Writers
    • Christianity and Islam
    • Ethelyn's Mistake
    • Indiscretions of Archie
    • James Fenimore Cooper
    • John Halifax, Gentleman
    • Letters to His Son on the Art of Becoming a Man of the World and a Gentleman, 1751
    • Louisa of Prussia and Her Times
    • More Fables
    • New Irish Comedies
    • Our Gift
    • Punch, or the London Charivari, Volume 156, June 11, 1919
    • Roddy McCorley
    • Scientific American Supplement, No. 520, December 19, 1885
    • The Atlantic Monthly, Volume 03, No. 18, April, 1859
    • The Great Salt Lake Trail
    • The Store Boy
    • The Trail of the White Mule
    • Thomas Wingfold, Curate V2
    • Those Extraordinary Twins
    • Tom Swift and His Great Searchlight; or, on the border for Uncle Sam
    • Twelve Types
    • Volume 19, No. 555, Supplementary Number
37. Olson, Oscar Ludvig - The Relation of the Hrolfs Saga Kraka and the Bjarkarimur to Beowulf A Contribution To The History Of Saga Development In England And The Scandinavian Countries
38. Omond, George W. T. (George William Thomson), 1846-1929
    • Bruges and West Flanders
    • Peeps At Many Lands: Belgium
39. Onions, Oliver [pseud.], 1873-1961 - Widdershins
40. Oppenheim, E. Phillips (Edward Phillips), 1866-1946
    • A Lost Leader
    • A Maker of History
    • A Millionaire of Yesterday
    • A People's Man
    • A Prince of Sinners
    • An Amiable Charlatan
    • English Fairy Tales
    • Havoc
    • Jeanne of the Marshes
    • Kingdom of the Blind
    • Nobody's Man
    • Peter Ruff and the Double Four
    • The Avenger
    • The Betrayal
    • The Black Box
    • The Box with Broken Seals
    • The Cinema Murder
    • The Devil's Paw
    • The Double Life Of Mr. Alfred Burton
    • The Double Traitor
    • The Evil Shepherd
    • The Governors
    • The Great Impersonation
    • The Great Prince Shan
    • The Great Secret
    • The Illustrious Prince
    • The Life of St. Declan of Ardmore
    • The Lighted Way
    • The Lost Ambassador The Search For The Missing Delora
    • The Malefactor
    • The Mischief Maker
    • The Pawns Count
    • The Profiteers
    • The Survivor
    • The Tempting of Tavernake
    • The Vanished Messenger
    • The Yellow Crayon
    • The Zeppelin's Passenger

41. Oppenheim, James, 1882-1932 - The Nine-Tenths
42. Optic, Oliver, 1822-1897
    • A Victorious Union
    • Across India Or, Live Boys in the Far East
    • Fighting for the Right
    • Haste and Waste; Or, the Young Pilot of Lake Champlain. a Story for Young People
    • Now or Never The Adventures of Bobby Bright
    • On The Blockade
    • Poor and Proud, or the Fortunes of Katy Redburn: a Story for Young Folks
    • Stand By The Union
    • Taken by the Enemy
    • The Mahabharata of Krishna-Dwaipayana Vyasa, Volume 2 Books 4, 5, 6 and 7
    • Within The Enemy's Lines
43. Orbeck, Anders, 1891- [Translator]
    • — Catiline, the Warrior's Barrow, Olaf Liljekrans
    • Or, in Quest of the Field of Diamonds
    • The Woman Who Did
44. Orcutt, William Dana, 1870-1953 - The Lever A Novel
45. Orczy, Emmasku Orczy - The Scarlet Pimpernel
46. Orczy, Emmuska, Baroness, 1865-1947
    • Castles in the Air
    • El Dorado, an adventure of the Scarlet Pimpernel
    • The Elusive Pimpernel
    • The League of the Scarlet Pimpernel
    • The Nest of the Sparrowhawk
    • The Nuttall Encyclopaedia Being a Concise and Comprehensive Dictionary of General Knowledge
    • The Old Man in the Corner
    • The Scarlet Pimpernel
47. Ormsby, John, 1829-1895 [Translator]
    • Ballads of a Bohemian
    • Malbone: an Oldport Romance
    • Riders to the Sea
48. Ornsby, Robert, 1820-1889
    • — Volume 6 Old-Fashioned Tales
    • — Volume 7 Stories of Courage and Heroism
    • Masterpieces of American Wit and Humor
    • Memoirs of James Robert Hope-Scott, Volume 2
49. Orr, Charles Ebert
    • Food for the Lambs; or, Helps for Young Christians
    • How to Live a Holy Life
50. Orr, John William [Illustrator]
    • Amerigo Vespucci
51. Orr, Lydon
    • — Complete
    • — Volume 1
    • — Volume 2
    • — Volume 3
    • — Volume 4
52. Orr, Mrs. Sutherland, 1828-1903 - A Handbook to the Works of Browning (6th ed.)
53. Orth, Samuel P. - Our Foreigners A Chronicle of Americans in the Making
54. Orth, Samuel Peter, 1873-1922
    • A chronicle of the organized wage-earners
    • The Boss and the Machine; a chronicle of the politicians and party organization
55. Ortiz, Cornelia [Editor]
    • A Husband by Proxy
    • Letters from France
    • Siouan Sociology
    • The Sky Is Falling
    • Tom Slade at Temple Camp
    • Winner Take All
56. Orton, George W., 1873-1958 - Bob Hunt in Canada
57. Orton, James, 1830-1877 - The Andes and the Amazon Across the Continent of South America
58. Osborne, Dorothy, 1627-1695 - The Love Letters of Dorothy Osborne to Sir William Temple, 1652-54
59. Osborne, Oliver T. (Oliver Thomas), 1862-1940 - Disturbances of the Heart
60. Osbourne, Lloyd, 1868-1947
    • Love, the Fiddler
    • The Motormaniacs
61. Osgood, Charles Grosvenor, 1871-1964 [Editor]
    • Abridged and edited, with an introduction by Charles Grosvenor Osgood
    • Pagan and Christian creeds: their origin and meaning
    • The San Francisco calamity by earthquake and fire
62. Osler, Edward, 1798-1863 - The Life of Admiral Viscount Exmouth
63. Osler, William, 1849-1919 - A Series of Lectures Delivered at Yale University on the Silliman Foundation in April, 1913
64. Osmer, William - A Dissertation on Horses
65. Ossendowski, Ferdinand, 1876-1945 - Beasts, Men and Gods
66. Ossoli, Margaret Fuller, 1810-1850
    • Memoirs of Margaret Fuller Ossoli, Volume I
    • Memoirs of Margaret Fuller Ossoli, Volume II
    • Woman in the Ninteenth Century and Kindred Papers Relating to the Sphere, Condition and Duties, of Woman.
67. Ostrovsky, Aleksandr Nicolaevich, 1823-1886
    • Plays
    • The Storm
68. Otis, Charles P. (Charles Pomeroy), 1840-1888 [Translator]
    • A Daughter of To-Day
    • A Knight of the Nineteenth Century
    • A Sketch of the Causes, Operations and Results of the San Francisco Vigilance Committee of 1856
    • A Strange Disappearance
    • — Volume 01
    • — Volume 06
    • — Volume 1
    • — Volume 1 [Historic court memoirs]
    • — Volume 3
    • — Volume 4
    • — Volume 54, No. 333, July 1843
    • By the Ionian Sea
    • Complete Project Gutenberg William Dean Howells Literature Essays
    • Drusilla with a Million
    • Elsie's Kith and Kin
    • Grand'ther Baldwin's Thanksgiving with Other Ballads and Poems
    • Hopes and Fears for Art
    • International Weekly Miscellany - Volume 1, No. 7, August 12, 1850
    • Lady Mary and her Nurse
    • Lancashire Idylls (1898)
    • Literary Copyright
    • My Lady Caprice
    • Notes and Queries, Number 53, November 2, 1850
    • Or, the Secret of Ruby Mountain
    • Quaint Gleanings from Ancient Poetry
    • Quit Your Worrying!
    • Rosy
    • Ruth
    • St. George and St. Michael Volume I
    • The American Spirit in Literature : a chronicle of great interpreters
    • The Art of Letters
    • The Beautiful Lady
    • The Circus Boys in Dixie Land : or, Winning the Plaudits of the Sunny South
    • The Collected Works of Ambrose Bierce, Volume 1
    • The Freelands
    • The Lady of the Lake
    • The Quaker Colonies, a chronicle of the proprietors of the Delaware
    • The Rubaiyat of Omar Khayyam Jr.
    • The Stokesley Secret
    • The Student's Elements of Geology
    • The Tale of Peter Rabbit
    • Volume 17, No. 097, January, 1876
69. Otis, James, 1848-1912
    • A District Messenger Boy and a Necktie Party
    • Neal, the Miller
    • Richard of Jamestown : a Story of the Virginia Colony
    • The Minute Boys of the Mohawk Valley
    • Toby Tyler
70. Ouida, 1839-1908
    • A Dog of Flanders
    • Bebee
    • Findelkind
    • The Waters of Edera
    • Under Two Flags
71. Overbeck, Bertha [Translator]
    • A Dissertation on Horses
    • — Aeschylus and Sophocles
    • — Volume 3
    • ée
    • Dame Care
    • My Man Jeeves
    • Our American Cousin
    • Patty's Suitors
    • Stray Pearls
    • The Malady of the Century
    • The War Terror
72. Overton, Jacqueline M. - The Life of Robert Louis Stevenson for Boys and Girls
73. Overton, Mark - Jack Winters' Gridiron Chums
74. Owahyah - Birch Bark Legends of Niagara
75. Owen, Luella Agnes, 1852-1932 - Cave Regions of the Ozarks and Black Hills
76. Owen, R. Emmett (Robert Emmett), 1878-1957 [Illustrator]
    • A Jolly by Josh
    • A Story of the Reign of Queen Anne
    • An Introductory Course of Quantitative Chemical Analysis With Explanatory Notes
    • Back to Methuselah
    • Bambi
    • Daniel Defoe
    • Dew Drops, Vol. 37, No. 08, February 22, 1914
    • Dick Prescott's Third Year at West Point Standing Firm for Flag and Honor
    • Dixon's Return Odd Craft, Part 10.
    • Flowers and Flower-Gardens With an Appendix of Practical Instructions and Useful Information Respecting the Anglo-Indian Flower-Garden
    • History of the World War An Authentic Narrative of the World's Greatest War
    • Life And Letters Of John Gay (1685-1732)
    • Manual of Ship Subsidies
    • Miriam Monfort A Novel
    • Now or Never The Adventures of Bobby Bright
    • Punch, or the London Charivari, Volume 100, May 9, 1891
    • Sheila of Big Wreck Cove A Story of Cape Cod
    • The Bay State Monthly, Volume 3, No. 1
    • The Founding of the Trans-Alleghany Commonwealths, 1784-1790
    • The Go Ahead Boys and Simon's Mine
    • The History of Puerto Rico From the Spanish Discovery to the American Occupation
    • The Insurrection in Dublin
    • The Roll-Call
    • This Is the End
    • Tom Slade on Mystery Trail
77. Owen, Wilfred, 1893-1918 - Poems
78. Oxenford, John, 1812-1877 [Translator]
    • A Child's Garden of Verses
    • A Tale of Youth and Summer Time and the Baxter Family Especially William
    • Eight Hundred Leagues on the Amazon
    • Icelandic Primer with Grammar, Notes and Glossary
    • Or, the stirring cruise of the motor boat Gem
    • Poems of Cheer
    • The Fatal Boots
    • Under the Red Robe
    • Vignettes of San Francisco
79. Oxenham, John, 1852-1941
    • A Little Book of Thoughtful Verse
    • A Maid of the Silver Sea
    • Carette of Sark
80. Oxley, J. McDonald - The Young Woodsman Life in the Forests of Canada

81. Oxley, John, 1781-1828 - Journals of Two Expeditions into the Interior of New South Wales
82. Oxonian, An - Thaumaturgia
83. Oyen, Henry, 1883-1921 - The Plunderer
84. Oziminski, Wojciech [Translator]
    • English Literature, Considered as an Interpreter of English History Designed as a Manual of Instruction
    • Salomy Jane
    • The Ceremonies of the Holy-Week at Rome