Contents: • Old Faithful by Raymond Z. Gallun • Helen O'Loy by Lester del Rey • Requiem by Robert A. Heinlein • Some Curious Effects of Time Travel by L. Sprague de Camp • The Cold Equations by Tom Godwin • Plus X by Eric Frank Russell • The Big Front Yard by Clifford D. Simak • "What Do You Mean ... Human?" by John W. Campbell, Jr. • Home Is the Hangman by Roger Zelazny • Eyes of Amber by Joan D. Vinge • Ender's Game by Orson Scott Card