Continuity mistake: When Stan empties the unbroken pigeon's egg from the mug, he places the mug on the organ with his right hand and the handle is pointing left, but in the next shot the handle is now pointing right.
Continuity mistake: When Stan and Oliver run away after picking up the wallet, Oliver has it. But when they crash into the policeman, Stan now has the wallet.
Continuity mistake: When Oliver is laughing after Stan tossed the woman's bucket in the street, the top of Oliver's coat and his bowler hat are covered in snow. In the next shot, the snow has disappeared.