In the shoot out at the St. George Hotel, the police fire at least 6 times at the thief who stole the wallet while he is in front of a large glass window and glass revolving doors. The police miss hitting the thief several times, but still don't break any of the glass that he is standing right in front of.
Dick Powell and Jack Oakie put down $30,000 on a horse at 2-1 odds. Upon winning, they go to the bookie and demand their $60,000. 2-1 odds would pay $90,000 ($60,000 winnings plus their original $30,000).
In 1896 Cigolini (Jack Oakie) shoos away a (horse-drawn) cabbie with the injunction, "23, Skidoo!" That phrase only became a popular fad in 1905, and there's no record of "23" even by itself as slang before 1899.
When the people are standing on the bridge after Stevens dived in the river , the piece of clothe resembling the sky is clearly visible behind them thanks to the wrinkles on it.