Short story; Illustrations by Schneeman.

Short story Appeared in the collected works [i]Mr. Mergenthwirker's Lobblies and Other Fantastic Tales[/i], published in 1946, reissued in 1974. Appeared in the anthology [i]Baseball 3000[/i], edited by Frank D. McSherry, Jr., Martin H. Greenberg and Charles G. Waugh, published in 1981.

Short story. Illustrations by C.R. Thomson.

Short story. Illustrations by Schneeman. Appeared in the anthology [i]Travelers of Space[/i], edited by Martin Greenberg, published in 1951.

Serial novel: 1st of 2 parts. Illustrations by H. Wesso.

Serial novel: conclusion

Science article

Volume XXII, Number 6. Published by Street & Smith Publications, Inc., 79 7th Ave., New York, NY. Editor, John W. Campbell, Jr.; cover artist, Hubert Rogers; illustrators, Binder, Brown, Rogers, Orban, Schneeman and Wesso.

Feature serial: 1st of 3 parts. H. Wesso, illustrator. Appeared as a complete novel in 1950 under the same title, reprinted in 1964, 1967, 1969, 1970, 1982, 1985 and 1988. Synopsis on Wikipedia: http://en.wikipedia.org/wiki/Cosmic_Engineers

Novelette. H. Wesso, illustrator Appeared in the collected works [i]The Best of Jack Williamson[/i], published in 1978, reissued in 1984; and [i]The Crucible of Power[/i], published in 2006. Appeared in the anthology [i]Five Science Fiction Novels[/i], edited by Martin Greenberg, published in 1952.