When the police van drops Stan and Ollie off at prison the prison is located in a metropolitan city area but when Stan and Ollie try to escape and the warden shoots them with a gun the prison is located in a rural, forested area.
At the end of the film the car backs into the truck, just before the impact two barrels of whitewash tip over.
Before the duo starts chopping the tree, ax marks on the trunk are already visible.
When Ollie loses his hat and Stan impales it on his pick. He raises the pick with the hat on it. However as he moves the pick around. You can see several additional holes in the hat. Obviously from previous takes.