Them Thar Hills.

Stan and Ollie travel to the mountains for Ollie's health, and park their caravan near a well into which a gang of moonshiners have earlier dumped their moonshine; and the boys proceed to quench their thirst thinking that it is iron-rich mountain water. The real trouble doesn't begin, though, until a married motoring couple stop by to borrow some gasoline, and the already-cranky husband leaves his thirsty wife with the boys while he goes off to refill his car's empty gas-tank. A sequel was made to this film: TIT FOR TAT, q.v.