When the car which was involved in the gun fight rolls to a stop, it stops on regular road. In the next shot it has been moved on to a train track.
In the runaway bus sequence, when Harold is on the topless bus trying to gain access to the wheel, his boater is knocked toward the rear of the bus by the banner hanging over the roadway. In the next scene, we see him wearing the hat and climbing onto the bonnet of the bus. When he slips on the banana peel and falls down by the front lights he is no longer wearing the hat. When he crashes through the windscreen, again, the hat is not with him. When the motorcycle policeman attempts to ticket him, however, he grabs the boater from the inside of the vehicle and makes good his escape.