US Patent 7596877 Mason's adjustable alignment tool

A stone wall alignment tool for checking the plumbness of a stone wall during construction thereof. The tool comprises a first “L” shaped bracket having a long leg and a short side leg. The tool also comprises a second “L” shaped bracket having a long leg and a short side leg, wherein the long legs of the first and the second brackets are slidably and lockingly adjustable with respect to one another, and wherein the long legs are arranged to be disposed on top of a wall and its side legs are arranged to be disposed on the sides of the stone wall as a plumb-alignment-tool during the wall's construction.