While the term "omnibus" has sometimes been used to describe Anthologies, as in the title of Groff Conklin's anthology Omnibus of Science Fiction (anth 1952), it is better reserved for volumes in which complete novels predominate. It is commonplace for veteran authors to republish three or more of their novels in single volumes, especially if they are parts of a trilogy or Series – a well-known example being Isaac Asimov's The Foundation Trilogy (omni 1963) – and for publishers of Shared World properties to reissue novels by different contributors in such packages. Occasional volumes will bring together original novels and Sequels by Other Hands, like Arthur C Clarke's and Gregory Benford's Beyond the Fall of Night (anth/omni 1990; vt Against the Fall of Night and Beyond the Fall of Night 1991), which combines the original version of Clarke's Against the Fall of Night (November 1948 Startling 1953; exp and much rev vt The City and the Stars 1956) with Benford's sequel; and Frederick Paul Walter's The Sphinx of the Ice Realm: The First Complete English Translation: With the Full Text of The Narrative of Arthur Gordon Pym by Edgar Allan Poe (anth/omni 2012), which offers Edgar Allan Poe's The Narrative of Arthur Gordon Pym of Nantucket (1838) as an appendix to Jules Verne's sequel Le Sphinx de glaces (1897).
However, omnibuses with unrelated novels by different authors are relatively rare, unless one counts Dos-à-Dos publications like the renowned Ace Doubles published by Ace Books (whose two halves are invariably listed in this encyclopedia as single titles for convenience of citation). E F Bleiler and T E Dikty edited three volumes entitled Year's Best Science Fiction Novels (anth 1952-1954), but these were collections of novellas, not novels. Henry Weber's Popular Romances (anth/omni 1812) did feature some relevant novels including Gulliver's Travels (1726; rev 1735) by Jonathan Swift, and Henry Morley's Ideal Commonwealths (anth/omni 1885) usefully assembled several works of Proto SF such as Thomas More's Utopia (1516; trans 1551); but the first true collection of science fiction novels was Donald A Wollheim's The Portable Novels of Science (anth/omni 1945), which questionably represented the genre with H G Wells's The First Men in the Moon (November 1900-April 1901 Cosmopolitan; 1901), John Taine's Before the Dawn (1934), Olaf Stapledon's Odd John: A Story Between Jest and Earnest (1935), and H P Lovecraft's "The Shadow Out of Time" (cut June 1936 Astounding; restored in The Outsider and Others, coll 1939).
Further examples include: the supernatural-themed Witches Three (anth/omni 1952), anonymously edited by Fletcher Pratt, first in the short-lived Twayne Triplets sequence; the anonymously edited The Paranoid Fifties: Three Classic Science Fiction Novels (anth/omni 1995) [for contents see Anonymous SF Editors]; the massive British Future Fiction 1700-1914 (anth/omni 2001 8vols) edited by I F Clarke; Gary K Wolfe's widely praised Library of Congress compilations, American Science Fiction: Four Classic Novels, 1953-1956 (anth/omni 2012) and American Science Fiction: Five Classic Novels, 1956-1958 (anth/omni 2012); and The First Science Fiction Novel Megapack: Featuring Six Great Science Fiction Novels (anth/omni 2016), anonymously edited [for contents see Anonymous SF Editors]. As shown above, this encyclopedia uses the designation "anth/omni" for omnibus volumes including two or more novels with different bylines, reserving "omni" alone for similar assemblages by a single author or House Name.
Since many would agree with the claim in the introduction to Wollheim's above-cited The Portable Novels of Science that the novel represents "the science-fiction story in its most powerful form", it is arguably incongruous that so few anthologists have endeavoured to present their favourites in a single volume. [GW/DRL]
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