The historical device that made copying drawings easier

One object within the institution’s collection can trace its principles back to ancient Greece: the pantograph (the type used for copying and scaling diagrams, rather than the type mounted on the roof of a train to collect power).

A pantograph allowed an engineer to copy and scale line drawings long before photocopiers and CAD simplified the process. Consisting of mechanically linked arms whose arrangement must always contain a parallelogram, the arms of a pantograph include two points for pens to move in parallel. When one pen is moved to create a line, an identical line is drawn by the second pen. The position of the points for each pen can be adjusted to enable the duplicate drawing to be either an identical copy or a scaled copy. 

The pantograph in the institution’s collection was made from brass by Elliot Brothers in about 1850.

Images of the pantograph can be viewed in the IMechE's Virtual Archive in the ‘Technical drawing instruments’ section of the artefacts collection.