asked the Secretary of State for the Home Department the total number of convictions for espionage in Great Britain for the years 1935 and 1937, respectively?

The term "espionage" is not known to the criminal law. In 1935 there was one case of a man convicted on a charge under the Official Secrets Acts of communicating to an unauthorised person secret papers calculated to be useful to an enemy. There was no case of the kind in 1937.