A Chronology of Digital Computing Machines (to 1952)

A Chronology...The Jargon FileComputer Dictionary
Charles Xavier Thomas de Colmar (1785-1870), of France, makes his "Arithmometer", the first mass-produced calculator.
Charles Babbage (1792-1871), of London, having reinvented the difference engine, begins his (government-funded) project to build one by constructing a 6-digit calculator using similar geared technology.
Babbage produces a prototype segment of his difference engine, which operates on 6-digit numbers and 2nd-order differences (i.e. can tabulate quadratic polynomials). The complete engine was to have operated on 20-digit numbers and 6th-order difference, but no more than this prototype piece was ever assembled.
Pehr George Scheutz, Stockholm, produces a small difference engine in wood, after reading a brief description of Babbage's project.
Babbage produces the first design for his "Analytical Engine". Whether this machine, if built, would have been a computer or not depends on how you define "computer". It lacked the "stored-program" concept necessary for implementing a compiler; the program was in read-only memory, specifically in the form of punch cards. In this article such a machine will be called a "program-controlled calculator".
The final design had three punch card readers for programs and data. The memory had 50 40-digit words of memory and 2 accumulators. Its programmability included the conditional-jump concept. It also included a form of microcoding: the meaning of instructions depended on the positioning of metal studs in a slotted barrel. It would have done an addition in 3 seconds and a multiplication or division in 2-4 minutes.
Babbage's difference engine project is officially cancelled.
(Babbage was spending too much time on the Analytical Engine.)
Scheutz and his son Edvard Scheutz produce a 3rd-order difference engine with printer, and the Swedish government agrees to fund their next development.
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