A mechanical calculator, or calculating machine, was a mechanical device used to perform automatically the basic operations of arithmetic. Most mechanical calculators were comparable in size to small desktop computers and have been rendered obsolete by the advent of the electronic calculator.Surviving notes from Wilhelm Schickard in 1623 report that he designed and had built the earliest of the modern attempts at mechanising calculation. His machine was designed for multiplication and division (using 'Napier's bones') and had an innovative mechanical adding machine built into the base. The surviving notes do not make it clear whether Schickard's machine would have worked as well as he reported to Kepler and might well have jammed when a number of counters were forced to move simultaneously. Two decades later in 1642 Blaise Pascal decisively solved this particular problem with his independent invention of a mechanical calculator. The comparative roles and significance of Pascal and Schickard's important inventions is discussed in much greater detail in Schickard versus Pascal: An Empty Debate?Co-opted into his father's labour as tax collector in Rouen, Pascal designed the calculator to help in the large amount of tedious arithmetic required.; it was called Pascal's Calculator or Pascaline. Thomas' arithmometer, the first commercially successful machine, was manufactured two hundred years later in 1851; it was the first mechanical calculator strong enough and reliable enough to be used daily in an office environment. For forty years the arithmometer was the only type of mechanical calculator available for sale.The comptometer, introduced in 1887, was the first machine to use a keyboard which consisted of columns of nine keys (from 1 to 9) for each digit. The Dalton adding machine, manufactured from 1902, was the first to have a 10 key keyboard. Electric motors were used on some mechanical calculators from 1901. In 1961, a comptometer type machine, the Anita mk7 from Sumlock comptometer Ltd., became the first desktop mechanical calculator to receive an all electronic calculator engine, creating the link in between these two industries and marking the beginning of its decline. The production of mechanical calculators came to a stop in the middle of the 1970s closing an industry that had lasted for 120 years.Charles Babbage designed two new kinds of mechanical calculators, which were so big that they required the power of a steam engine to operate, and that were too sophisticated to be built in his lifetime. The first one was an automatic mechanical calculator, his difference engine, which could automatically compute and print mathematical tables. In 1855, Georg Scheutz became the first of a handful of designers to succeed at building a smaller and simpler model of his difference engine. The second one was a programmable mechanical calculator, his analytical engine, which Babbage started to design in 1834 ; ""in less than two years he had sketched out many of the salient features of the modern computer. A crucial step was the adoption of a punched card system derived from the Jacquard loom"" making it infinitely programmable. In 1937, Howard Aiken convinced IBM to design and build the ASCC/Mark I, the first machine of its kind, based on the architecture of the analytical engine; when the machine was finished some hailed it as ""Babbage's dream come true"".