The circle can be taken to epitomise perfection on a limited scale -

The hyperbola can be taken to illustrate the huge US contribution to computing which took it into some many millions of homes by the turn of the century.

The parabola (which has its centre at infinity) can be taken to epitomise the almost unbounded possibilities for the future of computing.

To the right you can see a complex timeline showing what are arguably the most important machines, ideas and moments in the development of the computer.

The full lines, linking machines/ideas to one another, represent influence which is relatively certain. However, it must be appreciated that some of these influences are much more powerful than others. A dotted line represents an influence which is either relatively weak or uncertain.

By no means does this diagram incorporate everything in the history of computing, but even at a simple level you can see how complex and diverse the relationships were between the men and the machines.

These three monoliths…

The shapes cut out of the three vertical pieces of the central structure are called conics. They are formed by ‘cutting’ a cone (see below). They are a PARABOLA, a CIRCLE (a special case of the ellipse) and a RECTANGULAR HYPERBOLA (a special case of the hyperbola.

These three curves are selected as being one of the simplest and oldest pieces of

mathematical knowledge applied to curves in two dimensions. This was a subject likely to have been studied at school by Turing, the common school text on the subject at the time having been published when he was 15 years old.

You may also have noted that the posts on which these stations stand make a 17 sided polygon. It was Gauss, possibly the greatest mathematician who ever lived, who discovered that this particular complex shape could be drawn with only a ruler and a pair of compasses.

The Charity is greatly indebted to Professor Brian Randell for his comments on an earlier draft of the wording used for this Commemoration. Responsibility for errors or misrepresentations that remain lie, of course, with this Charity. The trustees are aware of the difficulty of achieving full accuracy in the text and welcome comments on any points.