A drafting machine is a tool used in technical drawing, consisting of a pair of scales mounted to form a right angle on an articulated protractor head that allows an angular rotation. The protractor head (two scales and protractor mechanism) is able to move freely across the surface of the drawing board, sliding on two guides directly or indirectly anchored to the drawing board. These guides, which act separately, ensure the movement of the set in the horizontal or vertical direction of the drawing board, and can be locked independently of each other   The drafting machine was invented by Charles H. Little in 1901 (U.S. Patent No. 1,081,758), and he founded the Universal Drafting Machine Company in Cleveland, Ohio, to manufacture and sell the instrument.[3] Drafting machines were present in the design offices of European companies since the 1920s. It is curious to see how the Encyclopædia Britannica explicitly specifies 1930 as the year this tool was introduced, but...