Robert Heinlein was so prolific in his first few years of writing that John W. Campbell had to run his stories under pseudonyms so that he could crowd more than one story into an issue. That was the policy in those days; actually, more like a Rule. Presumably the thinking was that readers who didn’t like an author or who wanted the greatest variety in their reading would pass over a table of contents that contained the same name more than once. It was true throughout the pulp era and into the 1950s that some editors ran their magazines on the cheap, filling whole issues with single authors writing tripe at red-hot speed. Hard to imagine that John W. Campbell, helming the best magazine on the market, would be suspected of pawning off such inferior stories, though. Like so many things in the publishing industry, editors just knew what readers would or wouldn’t accept and hewed to those precepts with rigid adherence. In any case, Heinlein had fourteen appearances (including two three-part serials) in Astounding in 1941, competing against himself six times. Perhaps even more surprising, Campbell packed those into eight issues. Why he left Heinlein out of four issues, never used his name again until after the war, invented a second pseudonym, Caleb Saunders (for “Elsewhen” in the September 1941 issue), published only stories as by Anson MacDonald in 1942, and used yet another pseudonym, John Riverside, for his appearance in the Campbell-edited Unknown for “The Unpleasant Profession of Jonathan Hoag” seems deeply odd at this remove.
Were readers in on the joke? The fandom in-crowd knew almost as soon as the ink was dry on the page. All the way over in England, the Futurian War Digest shouted the news in its June 1941 issue, though the Sands of Time still thought the announcement, “At long last the news has been released in USA so we might as well tell you that both Anson MacDonald and Lyle Monroe are pseudonyms of Robert Heinlein,” was big news in its March 1942 issue. American fanzines obviously had the news sooner than mail reaching Britain during WWII. Some must have had suspicions when such classic Heinleinisms as “Solution Unsatisfactory” and “By His Bootstraps” appeared under the name Anson MacDonald in the May and October 1942 Astoundings. It’s harder to see how anyone would have guessed it earlier that year, when Sixth Column was the first MacDonald signed story, serialized in the January, February, and March 1941 issues and after only seven previous Heinlein stories. Sam Moskowitz, in Seekers of Tomorrow, calls the pseudonym “one of the poorest kept secrets in science fiction” but adds “among the general readers, it may have understandably seemed that an important new talent had appeared on the science-fiction horizon.” Campbell treated Heinlein and MacDonald as separate writers when talking about what was forthcoming – except once, when he assigned “Gulf” to Heinlein but ran it as MacDonald. If fans didn’t know, their heads must have exploded when Fantasy Press published Beyond This Horizon, another MacDonald serial, in 1948 and this book appeared under Heinlein’s name in 1949 without as much as a mention of MacDonald or Astounding.
August Derleth reviewed this book for the February 24, 1950 Madison Capital Times:
[B]etter than average science fiction.
Sixth Column: A science fiction novel of a strange intrigue, by Robert Heinlein. 1949, title #4, 256 pages, $2.50. 5000 copies printed.
Hardback, black cloth with red spine lettering. Red atomic symbol trailing chains to each side on front cover and on spine. Jacket design by Edd Cartier. “FIRST EDITION” on copyright page. No designated printer. 10 titles listed on back cover plus “The Best Buy of 1950” untitled. Gnome Press address given as 421 Claremont Parkway, New York 57.
NOTE: The subtitle, “A science fiction novel of a strange intrigue,” is normally never listed in bibliographies, but is present on the cover and title page.
Rear cover is identical to Pattern for Conquest except that each mentions the other book.