## Dr. John W. Mauchly

John W. Mauchly earned a Ph.D. in physics from Johns Hopkins University in 1932 and accepted a physics Professorship at Ursinus College in Philadelphia in 1933.

At Ursinus, Dr. Mauchly became interested in electronic computing circuitry. He assumed that a device that took advantage of vacuum tubes and electronic circuits had the potential to complete mathematical calculations far more quickly than existing mechanical computing devices.

Dr. Mauchly's interest in electronic computing led him to the Moore School of Electrical Engineering at the University of Pennsylvania, where he took a course on "Defense Training in Electronics" in the summer of 1941. At Penn he met a young, talented electrical engineer, J. Presper Eckert, who shared his interest in an electronic calculating machine.

The US Army Ordnance Corps was also interested in such a device. In the early 1940s, the Army was having difficulty completing all the ballistics calculations needed to prepare firing tables for the many new artillery pieces coming off the World War II assembly lines.

In July 1943, the Ordnance Corps' Ballistics Research Laboratory at Aberdeen Proving Ground (APG) offered Dr. Mauchly and Eckert a contract to develop ENIAC (Electronic Numerical Integrator and Computer), the world's first electronic computer. Dr. Mauchly applied his considerable talents to designing the computer while Eckert used his engineering skills to build reliable, efficient components.

Completed in late 1945, ENIAC was installed and unveiled at APG in February 1946. The massive machine weighed 30 tons, occupied 1,800 feet of floor space, and contained 17,468 vacuum tubes. However, it completed calculations 100 to 1,000 times faster than existing mechanical calculators. Computations on a projectile trajectory that used to take 20 hours could now be done in 30 seconds.

Even before ENIAC was completed, Dr. Mauchly and his team began working on EDVAC, a second-generation computer that could be internally programmed.

EDVAC joined ENIAC in August 1949, making the Proving Ground the world's premier computer center in the early 1950's. These computers calculated projectile and rocket ballistic trajectories, performed hydrogen bomb calculations, predicted weather patterns, and facilitated wind tunnel design. Dr. Mauchly died in Jnuary 1980.