LEO computer marks 60th anniversary
Summary: The LEO I belonged to the J Lyons tea-shop company and was used to add up the price of cakes and pies. ZDNet UK looks at the grandfather of enterprise computers, which ran its first program on 17 November, 1951
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LEO I
LEO I filled a large room and used 5,936 valves, with another 300-400 in auxiliary equipment, according to the LSE. LEO used 64 mercury tubes — each over five feet in length — for storage, each tube weighing half a ton. The components were assembled in racks to minimise the impact of equipment failure — engineers had to replace up to 50 valves per week during times of heavy failure rates.
This picture shows the LEO I built at Cadby Hall in Hammersmith.
Photo: LEO Computers Society
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Talkback
ENIAC was at the University of Pennsylvania.
Harvard had Mark 1 which was a mechanical device.
ENIAC was the first ALL ELECTRONIC Computer.
The article has been updated.