The Harvard Classics, originally known as Dr. Eliot's Five Foot Shelf, is a 51-volume anthology of classic works from world literature, compiled and edited by Harvard University president Charles W. Eliot and first published in 1909. Source texts are available on Internet Archive at https://archive.org/details/harvardclassics
Titles listed under each volume that are hyper-linked are completed and point to the Librivox catalog page.
(not available as compiled in Harvard Classics) On Friendship, On Old Age, and letters, by Cicero
(not available as compiled in Harvard Classics) Letters, by Pliny the Younger
Vol. 10. WEALTH OF NATIONS, ADAM SMITH
(complete) The Wealth of Nations, by Adam Smith
Vol. 11. ORIGIN OF SPECIES, DARWIN
(complete) The Origin of Species, by Charles Darwin
Vol. 12. PLUTARCH'S LIVES
(complete) Lives, by Plutarch
Vol. 13. AENEID, VIRGIL
(complete) Aeneid, by Virgil
Vol. 14. DON QUIXOTE, PART 1, CERVANTES
(complete) Don Quixote, part 1, by Cervantes
Vol. 15. Bunyan, The Pilgrim's Progress. Walton, Lives of Donne and Herbert.
Vol. 16. The Thousand and One Nights
Vol. 17. Folk-Lore and Fable: Aesop, Grimm, Anderson
Vol. 18. Modern English Drama: Dryden, Sheridan, Goldsmith, Shelley, Browning, Byron
Vol. 19. Goethe: Faust, Egmont, etc. Marlowe: Doctor Faustus
Vol. 20. Dante. The Divine Comedy
Vol. 21. Manzoni. I Promessi Sposi
Vol. 22. Homer. The Odyssey
Vol. 23. Dana. Two Years Before the Mast
Vol. 24. Burke. On the Sublime; Reflections on the Revolution in France, etc.
Vol. 25. J. S. Mill and Thomas Carlyle
Vol. 26. Continental Drama
Vol. 27. English Essays, Sidney to Macaulay
Vol. 28. English and American Essays
Vol. 29. Darwin. Voyage of the Beagle
Vol. 30. Faraday, Helmholtz, Kelvin, Newcomb, etc. (Scientific Papers)