For several years, Pratt held a succession of fringe literary jobs, such as editing a ‘mug book’ (a biographical encyclopedia), in which people of small importance were persuaded to pay money to have their pictures and biographies included. He also worked for one of those writers’ institutes that promise to turn every would-be scribbler into a Tolstoy and that keep the money coming in by fulsome flattery of the veriest bilge submitted to them. Later, as an established author, Pratt drew on these experiences in lecturing to writers’ groups on literary rackets.

In the late 1920’s, Pratt got a foothold as a freelance writer. From 1929 to 1935 he sold a number of science-fiction stories to Amazing, Wonder, and other science-fiction pulps of the time. He also worked for Hugo Gernsback, then publishing Wonder Stories. Pratt translated European science-fiction novels from the French and the German. Gernsback had a habit of not paying his authors what he had promised, but Pratt got around him. He would translate the first instalment or two of a European novel and then, when the material was already in print, say:

«I’m sorry, Mr. Gernsback, but if you don’t pay me what you owe, I don’t see how I can complete this translation.»

He had Gernsback over a barrel. He also took off more than a year to live in Paris on the insurance money that he collected after a fire gutted the Pratts’ apartment. He studied at the Sorbonne and did research for his book on codes and ciphers, Secret and Urgent.

Pratt learned Danish among other languages, spoke French with a terrible accent, and became friends with the curator of arms and armour at the Louvre, who once let him try on the armour of King Franзois I. In his day, the king had been deemed a large, stout man. The flyweight Pratt found all the armour too small except the shoulder pieces; Franзois had tremendous shoulders from working out with sword and battle-axe in the tilt yard.