The film is set in the 1880s due to the references to the Jack the Ripper murders, but features the infamous body snatchers Burke and Hare, who were around 60 years earlier--and in Edinburgh, Scotland, while the Ripper murders were in London, England.
Contrary to popular belief, Burke and Hare were not body snatchers, but murderers who sold their victims' bodies to Edinburgh's Royal College of Surgeons. However, the college did receive bodies of recently buried deceased removed from their graves by body snatchers. Additionally, Burke and Hare never operated outside of Edinburgh.
Jekyll's first transformation into Hyde is almost perfect, but it's obvious that the actor is still in the foreground and the actress only appears to be his mirror reflection. As their movements are not perfectly synchronous, they are clearly two different people.
Viruses were not identified until 1892, several years after the Ripper murders of 1888.
The prostitute killed at the film's beginning is wearing modern high-heeled shoes.