The Butcher's laboratory is dim and the equipment does not work. You need some power.
This is the low-spoiler guide for "Powering up the laboratory" puzzle in Gibbous - A Cthulhu Adventure. Unlike in normal walkthrough, you get gradual hints on how to solve the puzzle. Click the big button below to see your first hint. If the hint contains a spoiler, you will be warned about it before clicking.