Corrected entry: In 1887, when the movie takes place, a machine gun was not called a machine gun.It was referred to as a Gattling gun.The term machine gun didn't come into use until the mid 1920's.
Corrected entry: When Roy plunges into the water, when the bad-guy cuts the line, you can see he hits the line with his sword, which sparks but doesn't damage the line at all. The line simply begins to move rapidly as if cut.
Correction: Looking at it in slow-motion, you can see several lines of rope lying next to each other. The sword actually cuts the one in the front which quickly disappears to the left and makes the other ropes (actually a different part of the very same rope) move rapidly.
Corrected entry: In the scene where Chon is fighting in the library, he holds up numerous books as shields. The man's sword does not pierce the covers of the last two books, in fact it bends slightly. But Chon discards the books and grabs a new one each time.
Correction: Not a mistake. He can't pause between sword thrusts to check the integrity of each book.
Corrected entry: Chon Wang and Rathbone's swords simply vanish before they fall out of the clocktower.
Correction: They had already dropped their swords since they needed their hands to hold onto the platform.
Corrected entry: At the end we find out that the child is Charlie Chaplin and Owen Wilson is John Wayne. Well, Charlie Chaplin was born in 1889 and John Wayne was born in 1907. Charlie Chaplin is older than John Wayne, but in this movie they made him younger by what looks like 10-20 years.
Correction: Owen Wilson is not John Wayne. Jackie Chan is "Chon Wang" which sounds like "John Wayne." This is why he says "Chon Wang, movie star, it could work.", because it sounds like "John Wayne, movie star, it could work." They already said he was really Wyatt Earp in the first movie.
Corrected entry: Roy O'Bannon mentions his investment choice of being between cars or zeppelins. At least cars were only a couple of years away and were in the process of being invented. The zeppelin did not make its first flight for another thirteen years, on 2 July 1900, and was the brainchild of a German count - hardly the sort of person to go begging in America for support of his invention.
Correction: The inventor may have been traveling the world, searching for potential investors. He wasn't "begging", but merely showing off his ideas. People do that all the time.
Corrected entry: In the scene in the library when Chon and Roy are searching for a secret panel, when Chon trips the lever and starts the fireplace spinning, you see it happening with Roy in the foreground reading the Karma Sutra. If you look above Roy's right shoulder as the fireplace is spinning, when the fireplace is perpendicular to its normal position, you can see someone in the next room helping to spin the fireplace. This person cannot be the guards that Chon and Roy fight soon after, as you would have been able to see that person in a following shot when you see Chon inside the secret room and you can see the entire wall behind him. Also, the person appears to be wearing a hat. (00:47:45)
Correction: I believe this actually is a guard. He's flinching when he sees the fireplace rotate. After all, you see later the fireplace rotate many times and there appears to be nobody doing it.
Corrected entry: Big Ben does not immediately strike the hour, as portrayed in the movie. It actually plays a little tune first.
Correction: You hear the tune it plays earlier in the movie, in the background.
Corrected entry: In the library fight (deleted scenes archive, DVD version), a kick blows out four candles. In the next shot, all candles are burning again.
Correction: Keyword: Deleted scene. This doesn't count as a mistake in the actual movie.
Corrected entry: There are too many cars on the roads. The internal combustion engine was not to be invented for another two years, and hardly anybody drove the steam-powered ones invented in the 1870s.
Correction: There is only ONE CAR in the entire movie, Rathbone's car.
Corrected entry: Chon, Lin and Roy stay at a fairly decent hotel when they are in Whitechapel. Hotels as nice and clean as that did not exist in Whitechapel in 1887.
Correction: Apparently you didn't notice the building was a whorehouse. It's not a "clean place" at all.
Corrected entry: When Jackie And Owen fall from the clocktower, holding the flag, they fall into the Queens' caravan. They land on the seat opposite the Queen without going through to the ground. Even though they grabbed onto the flag, it wouldn't have made a difference. (01:36:50)
Correction: The flag slowed them quite enough to make them survive the fall, and then they crashed through the caravan's roof. That would slow them A LOT.
Corrected entry: In the fight scene in the market, Jackie Chan starts to chuck umbrellas from a stand at some members of the street gang. However, a few of the umbrellas shoot out at the baddies before Jackie Chan even touches them.
Correction: All the umbrellas launch only after Jackie Chan uses his umbrella to throw them. One or two of them do get caught on each other which can make it seem as though they are coming out quicker than they should be.
Corrected entry: After the scene with the pillow fight, the girl storms out. When she runs out of the hotel, she has black and white sneakers on which is odd for that time in history.
Correction: It is not 100% clear that they are sneakers. They look just like the chinese slippers she has on during the whole movie. Clearly shown later (after this scene) when she is tied up and you can see her red slippers with a white stripe.
Corrected entry: On the deleted scene when Roy and Chon are in armours, if you play it in slow motion, you can see that the guards stop BEFORE Roy sneezes.
Correction: Well the scene was deleted and really can't be considered a mistake.
Corrected entry: There's a point in the movie where Jackie Chan and Owen Wilson, while escaping in a car, crash into one of the stones of Stonehenge. Stonehenge is nowhere near London, yet it didn't seem to take them long to get there.
Correction: They reach Stonehenge from Rathbone's castle, which is not in London. It's never made clear exactly where it is so it could quite conceivably be near Salisbury Plain.
Corrected entry: In the scene on the barge where Jackie Chan and Donnie Yen are fighting it out, Fenn Wong finishes off Donnie Yen by firing a large firework at him which carries him over the river before exploding. According to one of Newton's Laws 'for every action there is an EQUAL and opposite reaction.' Therefore for the firework to have enough force to push Donnie Yen up into the air, it would have had to also push Fenn Wong back with the same force, and considering she is wearing slippered shoes and standing on a flat surface, she would have been pushed off the other side of the barge.
Correction: The firework is a rocket, therefore its equal and opposite reaction is the propellant. Fenn Wong can fire it without a opposite reaction on her.
Correction: The Gatling gun was just one of many early machine guns available in the late 19th century, including the Maxim machine gun, which existed at the time the movie was set (but was not adopted by any army until 1889).
J I Cohen