Boulder Passage 2 - Underground (Resident Evil)

This room contains a puzzle. You must use the Hex Crank on the small hex-shaped hole in the middle of the passage to rotate the midsection enough times to reveal a new offshoot leading to the Item Chamber.

This room also contains a large boulder blocking the western end. When you approach the boulder and then retreat away from it, it will start rolling towards you. The only way to escape it is to dive into one of the southern offshoots and allow the boulder roll past.