↑ Beside two arithmometer clone makers from Germany and England, the only other company to offer calculators for sale was Felt & Tarrant from the USA which started selling their comptometer in 1887 but had only sold 100 machines by 1890.
↑ Anthony Hyman, Charles Babbage, pioneer of the computer, 1982
↑ "The introduction of punched cards into the new engine was important not only as a more convenient form of control than the drums, or because programs could now be of unlimited extent, and could be stored and repeated without the danger of introducing errors in setting the machine by hand; it was important also because it served to crystallize Babbage's feeling that he had invented something really new, something much more than a sophisticated calculating machine." Bruce Collier, 1970
