Main part of a working model of a differential analyser constructed from the construction toy, Meccano, made by Professor Douglas Hartree and Arthur Porter at University of Manchester, England, 1934. Reconstructed by Prof. Douglas Hartree at University of Cambridge, England, 1947

Main part of a working model of a differential analyser constructed from the construction toy, Meccano, by Prof. Douglas Hartree and Arthur Porter at University of Manchester, England, 1934, and reconstructed by Prof. Douglas Hartree at University of Cambridge, England, 1947.

A differential analyser is an analogue computer designed to solve equations using a wheel and disk mechanism. This model was built using the toy Meccano over 18 months by research student Arthur Porter. Porter was working under the supervision of Professor Douglas Rayner Hartree (1897-1958), a professor of theoretical physics, who was waiting for a full-size analyser to be built. Although it needed setting and operating by hand, the machine was able to solve difficult equations.