Sherlock Holmes: Uh, hmm... Right. Where are the wagons?
Madam Simza Heron: The wagon is too slow. Can't you ride?
Dr. John Watson: It's not that he can't ride... How is it you put it, Holmes?
Sherlock Holmes: They're dangerous at both ends and... Crafty in the middle. Why would I want anything with a mind of its own bobbing about between my legs?
In the machine gunning of the train carriage scene the weapon would not have been available to the soldiers in 1891. While an order by the British army is said to have been placed in late 1888 for 120 Maxim guns it first saw only limited use during the First Matabele War of 1893. It officially entered British Service only in 1896, seeing action during the First Boer War.
The final chess match between Moriarty and Holmes is based loosely on a famous chess match between chess masters Bent Larsen and Tigran Petrosian. The match involved the sacrifice of a queen and a surprise checkmate, thus mirroring Holmes' apparent sacrifice of himself to stop Moriarty.