<P> The Automatic Sequence Controlled Calculator (Harvard Mark I) was the first operating machine that could execute long computations automatically . A project conceived by Harvard University's Dr. Howard Aiken, the Mark I was built by IBM engineers in Endicott, N.Y. A steel frame 51 feet long and 8 feet high held the calculator, which consisted of an interlocking panel of small gears, counters, switches and control circuits, all only a few inches in depth . The ASCC used 500 miles (800 km) of wire with three million connections, 3,500 multipole relays with 35,000 contacts, 2,225 counters, 1,464 tenpole switches and tiers of 72 adding machines, each with 23 significant numbers . It was the industry's largest electromechanical calculator . </P> <P> The enclosure for the Mark I was designed by futuristic American industrial designer Norman Bel Geddes . Aiken considered the elaborate casing to be a waste of resources, since computing power was in high demand during the war and the funds ($50,000 or more according to Grace Hopper) could have been used to build additional computer equipment . </P> <P> The Mark I had 60 sets of 24 switches for manual data entry and could store 72 numbers, each 23 decimal digits long . It could do 3 additions or subtractions in a second . A multiplication took 6 seconds, a division took 15.3 seconds, and a logarithm or a trigonometric function took over one minute . </P> <P> The Mark I read its instructions from a 24 - channel punched paper tape . It executed the current instruction and then read in the next one . A separate tape could contain numbers for input, but the tape formats were not interchangeable . Instructions could not be executed from the storage registers . This separation of data and instructions is known as the Harvard architecture (although the exact nature of this separation that makes a machine Harvard, rather than Von Neumann, has been obscured with the passage of time; see Modified Harvard architecture). </P>

How was the first automatic calculator mark i controlled