Ancient History - The Comptometer

The comptometer was a mechanical calculator that was widely used in the early 20th century to perform arithmetic calculations. It was invented by Dorr Eugene Felt in 1887 and became a popular tool for businesses and government agencies until the 1960s, when electronic calculators replaced them.

The comptometer consists of a keyboard with numbered keys arranged in columns, much like a modern computer keyboard. Each key represents a number from 0 to 9. The keys are attached to a series of gears and levers that are used to perform addition, subtraction, multiplication, and division.

To use a comptometer, a user would enter the first number by pressing the appropriate keys. They would then enter the operation they wanted to perform (+, -, x, ÷) by pulling a lever located below the keyboard. The user would then enter the second number, and the comptometer would perform the calculation and display the result in a window located at the top of the machine. The result could be read directly from the display, making it a quick and efficient tool for performing calculations.

Comptometers were used in a wide variety of applications, including accounting, payroll, and data entry. They were especially popular in large organizations such as banks, insurance companies, and government agencies that required accurate and efficient calculations. They were also used by individuals, such as accountants, bookkeepers, and clerks.

The comptometer was a groundbreaking invention that revolutionized the way calculations were performed in the early 20th century. Its speed, accuracy, and ease of use made it an invaluable tool for businesses and organizations of all sizes. Although it has been largely replaced by electronic calculators and computers, the comptometer remains an important part of the history of computing and a symbol of the ingenuity and innovation of its inventor, Dorr Eugene Felt.

My mother used one of these in the late 50's early 60's where she was a comptometer operator for The Saskatchewan Wheat Pool. 

Source: Some or all of the content was generated using an AI language model