Images of The Harwell Computer otherwise known as WITCH


'Computor fitted with 20 stores, but excluding tape readers, printers, and power supply. The left hand rack carries two units each of ten stores. The left centre rack carries the electronic pulse generator (top), the aritmetic units with left shift unit (centre) and the translator unit (bottom). The two right hand racks contain the relay sequence control circuits.'

From Electronic Engineering, August 1951. The image was also published in the NPL's issue of Automatic Digital Computation, 1953

The original image is copyright UKAEA


Seven paper tape readers, the printer (Creed 7 ?), and paper tape perforator.
This was photographed at Harwell.


The switch box in the centre of the table allow control of the machine away from the racks and main control panel.


The machine being used at Wolverhampton and Staffordshire College of Technology in 1961.

Mr F.J. Hawley (Senior lecturer in Mathematics) on right, and Peter Burden (Wolverhampton Grammer School boy) on left.
From Wolverhampton Express and Star May 27th, 1961

At this stage, Peter Burden was waiting to go up to Cambridge to read maths, but was using the machine regularly. Peter was asked to write a program for the Chubb lock company to produce listings of valid lock combinations according the specification they gave. This also led to modifications being made to the computer particular to do with print layout formats.

  Again in Wolverhampton. The gentleman in the suit on the right is Cecil Ramsbottom, and I suspect the chap making adjustments to one of the relay racks is either Charlie Uzzell or Eric Hugill.

Bernard Coleman with the WITCH (as it was named by then) at Wolverhampton.
Note the perspex covers on the racks aren't fitted at this point.

Picture from Wolverhampton Express and Star

  The machine in full in Wolverhampton with all 9 storage groups - 90 stores in all.
  WITCH installed in Wolverhampton pictured from the power supply end of the machine
  Six (five hole) paper tape readers (unknown type, not Creed and not Elliott) installed in Wolverhampton.

This is the image submitted to the Guiness Book of Records when the machine was listed as the Worlds Most Durable Computer. 1973

Cecil Ramsbottom is pictured next to the contrl panel.