There is no arguing – most people find economics pretty hard to follow and perhaps just a little dull.

But here is a great example of how to make something which is abstract and complicated (which a lot of science is) interesting and engaging.

The MONIAC (Monetary National Income Analogue Computer) invented in 1949 by New Zealand economist Bill Phillips to model the national economic processes of the United Kingdom.

He made the machine while student at the London School of Economics.

The MONIAC was an analogue computer which used fluid to model the workings of an economy.

Other computers went to Harvard Business School and the Roosevelt College in the United States, and Melbourne University. The Ford Motor Company and the Central Bank of Guatemala are believed to have bought MONIACs.

Perhaps we need to crank up the one at Melbourne Uni and pit it against Treasury modelling…..

Below is a picture of one at the Reserve Bank of New Zealand, a diagram of the MONIAC, an article from Fortune magazine in 1952 and a picture of Bill Phillips with a MONIAC.

More about them HERE


  1. Unfortunately the MONIAC at the Science Museum (Mathematics 2nd floor) is not currently working but by studying the schematic diagram on this page I think it is possible to write a program with vessels,pipes,sluice gates and dyed water that mimicks this machine. As in all great ideas there is a beauty and simplicity about this model that lays down the foundations for building a more complex model of an economy and how it can go wrong. I was immediately struck by this model after reading about it when teaching myself economics from a book written by an economist at LSE.

    1. Thanks. It is indeed a wonderful “machine” and I would love to have one up and running and pit it against modern electronic computer economic forecasting. Perhaps we should start a MONIAC “make it work” group?

  2. Does anyone remember MUDPAC? At least I think that was what is was called and stood for Melbourne University Dual(?) Path(?) Analogue Computer. It solved differential equations in the basement of the elec eng building in the early 70’s. It was quirky but seemed to work pretty well as I recall.

  3. Love the fact that Bill Phillips is holding a cigarette. Was there anywhere where people DIDN’T smoke in those days?

    Seriously, what an greatidea to use fluids to demonstrate economic modelling for goodness sake!

    I am enjoying this blog immensely! Random assortments of science goodies. Just what the bloggersphere needs!

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