Leonardo da Vinci's Design
'It all started 2 years ago in June 1994 on a trip to Boston. While visiting the "Boston Computer Museum", I bought a booklet named "The History of Computing" by Marguerite Zientara. On page 3 I saw an unusual picture of a calculator titled "Leonardo da Vinci's Calculator". I started asking around about this calculator, but the more I asked, the less I knew, as it is not mentioned in any other book. The calculator became a quest of mine for the last 2 years. It took dozens of emails, faxes, telephone calls and snail mail to gather the information comprising the story of this unusual replica.'

Erez Kaplan.

Source: Erez Kaplan, "The Controversial Replica of Leonardo da Vinci's Adding Machine."

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