A man, dazed from running into a temporal snag, appears in a radio factory, whereupon (before returning to his own time) he makes a radio that’s actually a Twonky, which promptly gets shipped to a Mr. Kerry Westerfield, who is initially quite confounded and amazed at everything it does.

Because of the story’s opening, I’m convinced the Twonky is from the future. The “temporal snag” that brought it to 1942 feels like an unexpected time rift to me, although the route back to the future is an intentional journey via an unexplained method.

Spaceman Garrard is the third pilot to attempt the trip to the binary star system of Alpha Centauri using the FTL drive invented by Dolph Haertel (the next Einstein!) The Haertel Complex stories provide little in the way of actual time travel, but this one does have minor relativistic time dilation and more significant differing time rates.

Hugh Farnam makes good preparations for his family to survive a nuclear holocaust, but are the preparations good enough to survive a trip to the future?

In his blog, Fred Pohl wrote about how Heinlein’s agent gave permission for Pohl publish the novel in If and to cut “five or ten thousand words in the beginning that were argumentative, extraneous and kind of boring” (and Pohl agreed to pay full rate for the cut words). But apparently, Heinlein “went ballistic” when he saw the first installment, so much so that when the book appeared as a separate publication, Heinlein made sure people knew who was responsible for the previous cuts by adding a note* that “A short version of this novel, as cut and revised by Frederik Pohl, appeared in Worlds of If Magazine.”

* The version of Heinlein’s note that Pohl recalled was much funnier than Heinlein’s actual note in our timeline, but sadly, we have lost track of where we saw Pohl’s version.