Engraving by R C Roffe of Charles Babbage as the Lucasian Professor of Mathematics at Cambridge after a family portrait. Babbage (1791-1871) conceived the idea of an advanced calculating machine to print mathematical tables in 1812. It was designed to evaluate any mathematical formula and have higher powers of analysis than his original difference engine. His use of pressure die-casting for quantity production of interchangeable parts is among the earliest documented use of this technique. Published by M Salmon, Mechanics Magazine Office. Issued as a frontispiece to Mechanics Magazine, vol XVIII, October 1832 – March 1833.