Phillip's Economic Computer, 1949.
© Science Museum / Science & Society Picture Library
Lower left detail of Phillip's Economic Computer, the machine conceived by Bill Phillips (1914-1975), a New Zealand-born engineer turned economist. Phillips designed the machine to demonstrate in a visual way the circular flow of money within the economy. Approximately fourteen machines were built, and this particular machine was used as a teaching aid at the London School of Economics. It ran until May 1992.