A new high-speed calculating machine using electronic valves has been completed in the University Mathematical Laboratory at Cambridge. It is known as EDSAC (Electronic Delay Storage Automatic Calculator) and can do addtion, multiplication and subtraction at a very high speed. There are over 3,000 valves used. Photo shows: Information needed by the machine to solve a problem is punched onto a paper tape. This is put through a tape-reader and the results are then printed automatically on a teleprinter. The tape-reader or inpout mechanism, showing punched tape, is seen here.