In all carpentry works, it is necessary to use a large wooden square of metal tubes. We can quickly and easily transform such a square into a spirit level. You only need to attach a short riser made of string and a weight to the longer vertical arm. The point remains on the shorter arm, at which the pawn is to be placed, when the arm is strictly horizontal. The measurement will be all the more accurate, for them the angle will have both legs longer.
