Plan 28: Builder Charles Babbage's Analytical Engine

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Plan 28 is working towards building Charles Babbage's Analytical Engine. For the latest news follow the Plan 28 blog.

About the project

For an introduction to Plan 28, read The 100-year Leap or the BBC News article Plan to build 'steam-powered PC'.

Latest information

Progress on understanding Babbage's Mechanical Notation

Major progress has been made decoding Trains diagrams – these are the ‘flow charts’ in Charles Babbage’s notational language. There are some 90 separate symbols in the alphabet denoting (a) the form of the part (lever, gear, pendulum, bar, rack, pinion...) and (b) type of motion (circular, linear, reciprocating...). The method we are using involves examining the symbols in the Train that describe a particular mechanism in the Engine (addition, carriage, warning, locking...) and from an existing knowledge of the function of the mechanism, infer the usage of the symbols used to describe each part.

Progress made to date encourages us to believe that the whole language will yield to this method.


Babbage's Language of Thought

Babbage has been called the 'great-uncle' of modern computing, a claim that rests simultaneously on his demonstrable understanding of most of the architectural principles underlying the modern computer, and the almost universal ignorance of Babbage's work before 1970.

There has been an explosion of interest both in Babbage's devices and the impact they might have had in some parallel history, as well as in Babbage himself as a man of great originality who had essentially no influence at all on subsequent technological development.

How is it that one individual working alone could have synthesised a workable computer design over quite a short period, designing an object whose complexity of behaviour so far exceeded that of contemporary machines?


Plan 28 now accepting donations

Plan 28's donation system is now online through JustGiving. Donations can be made in British Pounds, US Dollars, Euros and a number of other currencies. As a UK charity Plan 28 is eligible for GiftAid; tax payers in the UK can help the charity by signing the GiftAid form when they make a donation.

As Plan 28 is a very long project it is particularly helpful when we receive regular donations. The donation system is able to set up monthly donations for people who want to contribute a little each month over the long term.

Plan 28 can accept donations on the web or via mobile phone. For example, to donate £10 by phone text BABB37 £10 to 70070.

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