Like Amelia Reynolds Long before him, Harl Vincent looked to the Swiss physicist Auguste Piccard for inspiration. By the late 1930s, though, Professor Piccard had moved on from stratospheric ballooning and was investigating undersea exploration. At the time Vincent wrote "Undersea Prisoner", Professor Piccard had designed a small steel gondola that could withstand great external pressure, and an undersea version of a balloon filled with a lighter-than-water liquid to provide buoyancy. As it happened, Piccard's research was interrupted when the Germans invaded and occupied Belgium in 1940, and it was not until after World War II that he was able to complete work on an undersea balloon filled with gasoline. In the story, it is Professor Francis Augustine who makes Piccard's undersea balloon a reality, some seventy years after the original proposal -- which would place the story around the year 2007.
The early 21st century Vincent imagines is remarkably similar to the early 21st century we're living in now. He describes in vivid detail the media circus that greets Burke and Augustine when they emerge from their gondola onto the deck of the Scipio. There are hordes of
A couple points of interest: Zybyski's crime of kidnaping and murdering a small child is doubtless a reference to the Lindbergh kidnaping and the arrest and trial of Bruno Hauptmann, which occurred earlier in the decade and would still have been fresh in Vincent's mind. I note without comment that Vincent made his Hauptmann-analog a Pole rather than a German. The ship that rescues Burke and Augustine, the Scipio, would have been named after one of the Scipios of the late Roman Republic, either Scipio Africanus the elder, who defeated Hannibal of Carthage at the Battle of Zama, or his grandson-by-adoption Scipio Africanus the younger, who destroyed Carthage sixty years later. The choice of name doesn't seem to have any deeper meaning.
Editorial note: Raymond Palmer, the editor of Amazing Stories, didn't like long sections of scientific exposition in his stories. When he encountered one, he would either eliminate it altogether, or condense it and turn it into a footnote. Isaac Asimov pointed out where Palmer had done this to his story "The Weapon Too Dreadful to Use" in The Early Asimov. Palmer did the same with "Undersea Prisoner", reducing two of that story's passages to footnotes. In reproducing the story in this blog, I have taken the liberty of un-footnoting the two passages and re-inserting them into the main body of the text. I make no apologies.