Damon Knight was the first anthologist to take an explicitly historical perspective, publishing his first anthology at a time when SF was gaining a bit of literary respect, and genre historians were claiming SF antecedents as far back as Plato and Homer. With excerpts from 19th century works by Wells and Verne, A Century of Science Fiction was Knight's first take on the history of science fiction.

Knight's second big anthology supplemented the first, as later editors Silverberg and Dozois were to do, with a volume of longer stories, novellas or short novels. This volume includes three stories -- the first three -- that were originally, or since have been, published as separate books.

Knight's third big anthology parallels his first, with stories ranging from an 1898 work by H. G. Wells to a 1966 story by Sonya Dorman from Knight's own Orbit 1 original anthology, and a 1968 translation by Knight, in F&SF, of an 1887 story by J.-H. Rosny Aîné.

The idea for A Science Fiction Argosy, at nearly twice the length of the longest earlier volumes, was "simply to put together the biggest and most comprehensive collection of good science fiction that I possibly could", as he says in his introduction. Like Anthony Boucher's Treasury of more than a decade earlier, it includes full-length novels, and the contents are divided into two "books", though unlike Boucher these are published in a single physical volume. Knight's introduction also claims, "I think I have achieved a more faithful portrait of the field than ever before", so it's perhaps significant to note that this volume was published two years after the first Science Fiction Hall of Fame.

The final volume here, appearing only a couple months after Science Fiction Argosy, is clearly a fantasy counterpart to that book, though this volume isn't as along, nor does it declare the same ambition. Knight's introduction talks about "realms beyond our knowledge", and says "The stories in this book have been chosen because they gave me delicious glimpses into certain of these realms..."

Most reprinted authors in this group: H.G. Wells (5); Poul Anderson, Alfred Bester, Robert A. Heinlein (3 each). The photo shows paperback reprints of the first two books.