The Vanishing Private (1942)

Private Duck is a camouflage painter He paints a giant cannon with some very gaudy colors until Sergeant Pete explains that the point is to make it so the cannon cant be seen Donald finds a bucket of experimental invisible paint and makes the cannon disappear Pete isnt happy with this and knocks Donald into the paint then chases him until he runs into the general As Pete tries to explain Donald prods him with a cactus then goes off to steal some pies Eventually Pete goes berserk and starts throwing grenades willynilly and gets in more trouble with the general