Hartree differential analyser, 1934.
© Science Museum / Science & Society Picture Library
This Meccano model was built by Douglas Hartree (1897-1958), based on the differential analyser built in 1930 by Vannevar Bush at the Masachusetts Institute of Technology (MIT). A differential analyser consists of a number of interconnecting integrating mechanisms. Its purpose is to provide an analogue method of arriving at a numerical solution to a differential equation. Hartree went on to build a full scale machine at Manchester University.