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Adding machines that I have known: A personal History of Adding Machines, Calculators, and Computers.


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Modern Computers (2017)

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Scene from the movie " The Apartment" (1960). In the picture the actor Jack Lemmon is Baxter, an office drudge that works using the Rotary calculator. Notice that every desk have its own Rotary Calculator.

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Mr. Dix is in the picture using the bookeeping machine. True or false?

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For anyone not involved in adding, subracting, multiplication, or division before 1970 it's hard to imagine that digital computing  was not available. Not to mention eletronic spreadsheets, Microsoft Word, Blackberry, Ipad or Iphone.

Double QQ, a popular grade school tablet had a multiplication table on the back cover. We all learned the multiplication table.

There were various machines to help. Most were mechanical, some electrical, and some with pull handle. Most worked on the principle that multiplication is repeat addition and division is repeat subtraction.

With the adding machines you could hold down the number you wanted to multiply and pull the handle or cycle the machine and count the number of cycles for the number you wanted to multiply.

Later, for both , multiplication and division, machines would allow you to enter both numbers and the machine would cycle for the answer, while you sat and watched.

NO! I did not get my start with the Abacus but I have been aware of most of the other machines!

Gerald Dix


Gerald Dix

Natalia Lima