The Sultan can be heard laughing before it cuts to him climbing up the pole.
Curly's right eye is visibly swollen when he gets out of the horse costume.
Curly's hat gets caught by the rope and later it comes off when he tries to take the spear out of it.
Larry clearly does not get hit with the hammer, but he reacts as though he did.
Curly's clothing changes constantly throughout the chase scene at the circus. This is due to the fact that he was sweating a lot and wardrobe had to keep giving him a new shirt for many scenes.
When Moe takes the hoe from Curly, He hits Curly in the nose, and you can see the hoe bends as it must be rubber.
Curly's screams when he is trying to balance on the tightrope are clearly dubbed in.
A crew member can be seen sitting inside Mr. Herman's car when he gets out.
Wires can be seen supporting Curly's stunt double on the tightrope.
When Mr. Herman notices the mangled poster on the wall when he gets out of his car, he is angry, but when he walks over to see the new poster in its place, he is happy and gets angry again when he notices the ruined poster.