b. Features of the Mark I. The Mark I was 51 feet long and B feet high and
contained 760,000 parts. It was an electromechanical computer. Electromagnetic
relays automatically controlled internal operations, while 78 mechanical adding
the calculating machines, so that long calculations could be done without human
c. Use of the Mark I. During World War II, Allied intelligence
discovered that the Nazis were experimenting with an electronically directed
cannon. The Mark I was used to evaluate many complex mathematical formulas
and resulted in the discovery that such a cannon would never function. While
the Nazis wasted valuable research time on this project, the Allies were able
to ignore it as a military threat.
Figure 1-17. The Mark I computed complex ballistics tables using vast
quantities of punched paper. After World War II, it was used for
15 more years at Harvard University.
Section IV. ELECTRONIC PHASE
1-16. THE IMPETUS: WORLD WAR II
From the outbreak of World War II, the War Department's Ballistic Research Lab
at the Army's Aberdeen Proving Ground in Maryland had been trying to prepare artillery
firing tables for gunners in the field. Gun crews desperately needed these trajectory
tables so they could adjust their aim according to range, altitude, wind, temperature and
other conditions. Gunners in North Africa, for example, had been complaining that the
soft ground there caused unpredictable recoil of their cannon and threw off their aim.
With 750 different multiplications required to calculate a single trajectory path, and at
least 2000 trajectories per table, human operators (assisted by an inefficient Mark I) fell
increasingly behind. Therefore, the Army awarded 0,000 to the nearby University of
Pennsylvania's Moore School of Engineering to develop a computer that could handle
these trajectory calculations.