ORIGIN AND DEVELOPMENT
More than a hundred years ago, an English mathematician and actuary, Charles Babbage (1792-1871), designed a machine—or engine as he called it—that would carry out the sequences of mathematical operations. In the 1830’s he received a government grant to build an analytical engine whereby long chains of calculations could be performed. But he was unsuccessful, because the refined physical devices necessary for quantities of digital calculation were not yet developed. Only in the 1930’s did these physical devices become sufficiently versatile and reliable for a calculator of hundreds of thousands of parts to be successful.
The Automatic Sequence-Controlled Calculator at Harvard was largely the concept of Professor Howard H. Aiken of Harvard. It was built through a partnership of efforts, ideas, and engineering between him and the International Business Machines Corporation, in the years 1937 to 1944. The calculator was a gift from IBM to Harvard University. Some very useful additional control units, named the Subsidiary Sequence Mechanism, were built at the Harvard Computation Laboratory in 1947 and joined to the machine.
Fig. 1. Scheme of Harvard IBM Automatic
Sequence-Controlled Calculator.