"On August 17, 1835, Solymon Merrick of Springfield, Massachusetts patented the first wrench.
The wrench typology is inspired by typologies of prehistoric stone tools. Merrick’s patent was issued over two million years after the idea of wrench was first born.
The wrench basically includes notches at the mouth for gripping. The wrench is pulled at a right angle to the axes of the lever-action and the bolt or nut."