This is a very interesting object when considered within the history of the development of computer graphics, the work of the Basser Department of Computer Science at the University of Sydney and Bromley's career there. He began lecturing there in 1971 (?) and had started by building the KUKAC machine to teach himself how computers worked. At the time in the Basser Department work was beginning in the development of a computer graphics system based on a PDP-8 computer the department had acquired in 1967/8. The person who was leading that work was Doug Richardson who had been using the Departments KDF9 computer to produce a number of spirograph-like plots that used modulated versions of the equations that are also appropriate to the Spirograph. I don't exactly know when Bromley built this device but it is clearly around that time and may well have been a response to Richardson's work, the graphic designs that it produces being quite similar to ones that Richardson was producing with the KDF9 and plotter

The object is part of a collection relating to the history and development of calculating devices assembled by Assoc Professor Allan Bromley of Sydney University, comprising mathematical instruments, slide-rules, mechanical and electronic calculators, electronic analogue computers, computer components, kit computers, education computers, and associated ephemera.

Allan Bromley was a lecturer and researcher at the University of Sydney Basser Department of Computer Science from 1978 until his untimely death in August 2002. He specialised in Computer Architecture, Computer Logic and in particular the History of Computing. He was regarded as the world authority on Charles Babbage's Calculating Engines (instigating the building of the Difference Engine No.2 at the Science Museum London) and the Antikythera Mechanism and had extensive knowledge of calculators, analogue computers, logic, stereopsis, totalisators, clocks and time keeping and mechanical engineering.

Model of a spirograph machine consisting of a rectangular structure made of metal Meccano pieces and screws with four small circular brass feet at each corner of the base. A small wooden box with drill holes and an on/off switch is attached to the side of the model and houses a small electric motor. The box bears the text, 'Caution 240 Volts' in red ink. A white electrical cord with a brown plug is attached to the box. Underneath the metal structure are cogs, chains and metal rods. Sitting on the top of the metal structure are two circular cogs, attached to which are metal rods connected with screws and metal Meccano pieces. These rods join in the top centre where a drawing instrument can be secured. Under this is a cork base to hold a circular piece of paper onto which the spirograph is drawn. This spirograph works in the same fashion as a conventional 'pen powered' spirograph template in that it produces mathematical curves of the variety technically known as hypotrochoids and epitrochoids, except the gears are powered by the motor.

The model is accompanied by a cork cube with pins inserted into top, made of cork, metal and plastic. Cube includes a semi-circular shape cut out of the top middle, with four brown top sewing pins on one side of the cut out shape and four black pins on the other and in the cut out middle there are seven red top pins and one blue top pin. On the base it is written in black pen, 'ALLAN G / BROMLEY'.

Five spirograph drawings, made of black pen and paper, consists of a circular piece of cream paper with a spriograph drawing on each side in black pen. Around the edge of the paper are pin holes where it was secured onto the spirograph machine.

Made: Sydney, New South Wales; 1970 - 1975

Used: Sydney, New South Wales; 1970 - 1975

Please see parts.

2010/1/88

1970 - 1975

245 mm

500 mm

310 mm