Factual error: Based on the lottery poster, the movie is set in 1925. During the scenes in Tampico, numerous newer cars (closer to the 1948 filming) are present in the background.
Factual error: The movie takes place in 1860, yet Ripper wields an 1862 police model Colt revolver.
Factual error: At the start of the film the father (Cedric Hardwicke) alights from a LNER suburban train then walks to his Wimbledon home. The film is set in 1913 but the LNER was not formed until 1923. That apart, LNER suburban services did not serve Wimbledon. A few scenes later the father and mother are sending off their son at Liverpool Street Station on his journey to Osborne Royal Naval College at Dartmouth. Strange since Dartmouth would have been (and still is) reached from Waterloo.