This is a work of fiction. All the characters and events portrayed in this book are fictional, and any resemblance to real people or incidents is purely coincidental.

Copyright © 2004 by the estate of Murray Leinster.
"The Fourth-Dimensional Demonstrator" was first published in Astounding in December 1935. "A Logic Named Joe" was first published in Astounding in March 1946, under Leinster's real name of Will F. Jenkins. Gateway to Elsewhere was first published by Ace Books as a double novel in 1954 (coupled with A.E. Van Vogt's The Weapon Shops of Isher). The Pirates of Zan was first published in serialized form in Astounding in February–April 1959, under the title "The Pirates of Ersatz." It was reissued the same year by Ace Books as a double novel under the current title (coupled with Leinster's Med Ship story The Mutant Weapon). "Dear Charles" was first published in 1960 by Avon Books, as part of Leinster's anthology entitled Twists in Time. The Duplicators was first published in a shorter version in Worlds of Tomorrow in February 1964, under the title "Lord of the Uffts." The expanded version contained in this volume was reissued the same year by Ace Books as a double novel under the current title (coupled with Philip E. High's No Truce With Terra).

All rights reserved, including the right to reproduce this book or portions thereof in any form.

A Baen Book

Baen Publishing Enterprises
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ISBN: 0-7434-9910-7

Cover art by Kurt Miller

First printing, June 2005

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Production by Windhaven Press, Auburn, NH (www.windhaven.com)
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