Novelette. Illustrated by Michael Arndt. Appeared in the collected works [i]Hawk Among the Sparrows: There Science Fiction Novellas[/i], published in 1976 (reissued in 2001). Appeared in the anthologies [i]Analog 4[/i], edited by John W. Campbell, publsihed in 1966; [i]The Permanent Implosion[/i], edited by John W. Campbell, published in 1970; and [i]Analog: The Best of Science Fiction[/i], published in 1985.