The telephone handset Constable Crabtree uses at the police box wasn't widely produced until the 1930s.
When Constable Crabtree and Dr. Grace converse behind a vegetable barrow, the bunches of green onions topping the display are fastened with contemporary thin, blue rubber bands instead of twine.
Murdoch and Meyers go undercover and infiltrate Goldman's entourage as friends. It is illogical that after Murdoch's exposure as a policeman, no one questions Meyer' identity as a wannabe anarchist.