Mechanical calculator

A mechanical calculator, or calculating machine, is a machine that does basic arithmetic tasks by itself. These machines are like old desktop computers, but they are now replaced by electronic calculators and digital computers.

In 1642, Blaise Pascal made the first mechanical calculator. He created it to help his father, who was a tax collector, with difficult math work.

In 1672, Gottfried Leibniz began making a new machine called the Stepped Reckoner. This machine used a special part called the Leibniz wheel. It could remember numbers and move easily. Leibniz made two of these machines. The Leibniz wheel was used in many calculators for over 200 years, even until the 1970s with the Curta hand calculator. It was replaced when electronic calculators were made.

Thomas' arithmometer, made in 1851, was the first mechanical calculator that people could buy and use every day at work. For forty years, it was the only one available until the Odhner Arithmometer was made in 1890.

Charles Babbage designed two very advanced mechanical calculators. They were too complicated to build when he lived. One could make math tables by itself, called the difference engine. The other could be told what to do, called the analytical engine. In 1937, Howard Aiken worked with IBM to build a machine based on Babbage's design, called the ASCC/Mark I. Some people said it was like Babbage's dream coming true.

Ancient history

Further information: Arithmetic and Abacus

People have always wanted to make math easier and faster. Long ago, they used small objects like pebbles to help count. These later became beads on wires, called an abacus. The abacus was used all over the world.

After the abacus, a man named John Napier made numbering rods in 1617, called Napier’s Bones. But the first true mechanical calculator was made in 1642 by Blaise Pascal. Before this, there were also machines like odometers and the Antikythera mechanism. These early devices showed how people tried to make math work better.

Further information: Pascal's calculator

The 17th century

The 17th century was when mechanical calculators began. In 1642, Blaise Pascal invented the first one. He made a machine that could do basic math by itself. Before this, people did all calculations by hand, which was slow and tiring.

Other tools like Napier's bones, logarithmic tables, and the slide rule were also used to help with math. These tools were easier for multiplying and dividing than early mechanical calculators. It wasn’t until the mid-1800s that mechanical calculators became more common.

The 18th century

Further information: Pinwheel calculator and Leibniz wheel

The 18th century was when inventors made the first machines that could multiply numbers by themselves. In 1709, an Italian inventor named Giovanni Poleni made a wooden calculator that could multiply, but a person still had to help with division. Other inventors, like Anton Braun from Germany and Hillerin de Boistissandeau from France, also created interesting machines. These early machines were important steps before we had the calculators we use today.

The 19th century

Luigi Torchi built the first machine that could multiply directly in 1834. This was also the second machine where you could press keys to use it, after James White made one in 1822.

The business of making mechanical calculators started in 1851 when Thomas de Colmar introduced his simpler Arithmomètre. This was the first machine people could use every day in an office.

For 40 years, the arithmometer was the only mechanical calculator people could buy, and it was sold all around the world. Another company, Felt and Tarrant, sold 100 comptometers in just three years.

The 19th century also saw the designs of Charles Babbage for calculating machines. First, he worked on his difference engine, starting in 1822. This was the first automatic calculator because it used the results of one operation for the next one. Later, he designed the analytical engine, starting in 1834. This was the first programmable calculator and it showed the ideas that later led to mainframe computers in the middle of the 20th century.

Desktop calculators produced

• In 1851, Thomas de Colmar made his arithmometer simpler by taking out the part that could only multiply or divide by one digit. This made it easier to add, but it could still multiply and divide if you turned a handle. This version was strong and reliable, and people began using it in banks, insurance companies, and government offices.
• In 1878, a company in Germany made a copy of Thomas' arithmometer. Before this, Thomas was the only person making these machines. Eventually, twenty European companies made copies of his arithmometer until World War II.
• Dorr E. Felt in the U.S. created the Comptometer in 1886. It was the first machine where pressing the keys would add numbers without needing to turn a handle. In 1887, he started a company with Robert Tarrant. The comptometer-type calculator later got an all-electronic engine in 1961.
• In 1890, W. T. Odhner started making his calculator again in his workshop in Saint Petersburg. He built and sold 500 machines in 1890. Later, he sold the Berlin part of his factory, and another company made machines under the name Brunsviga. Millions of these were sold until the 1970s.
• In 1892, William S. Burroughs began selling his printing adding calculator. His Burroughs Corporation became very important in making accounting machines and computers.
• The "Millionaire" calculator came out in 1893. It could multiply directly by any digit, and it had a special part to look up products.

Automatic mechanical calculators

• In 1822, Charles Babbage showed a small part of his difference engine. This machine could hold and work with seven numbers that had up to 31 digits each. It was the first machine that could work automatically, using the results from one operation for the next one. Development of this machine, later called "Difference Engine No. 1," stopped around 1834.
• In 1847, Babbage began working on an improved version called "Difference Engine No. 2." Neither of these designs was fully built by Babbage. In 1991, the London Science Museum built a working version of Difference Engine No. 2 using 19th-century technology.
• In 1855, Per Georg Scheutz finished a working difference engine based on Babbage's design. It was the size of a piano and was shown at the Exposition Universelle in Paris in 1855. It was used to make tables of logarithms.
• In 1875, Martin Wiberg redesigned the Babbage/Scheutz difference engine and built a smaller version the size of a sewing machine.

Programmable mechanical calculators

• In 1834, Babbage began designing his analytical engine, which would become the ancestor of modern mainframe computers. It had separate ways to put in data and programs, printers to show results, a part to process information (mill), memory (store), and the first set of programming instructions. In 1937, when Howard Aiken asked IBM for money to make the Harvard Mark I, he mentioned Babbage's ideas.
• In 1843, while translating a French article about the analytical engine, Ada Lovelace wrote an algorithm to calculate the Bernoulli numbers. This is considered the first computer program.
• From 1872 to 1910, Henry Babbage worked on creating the mill, the "central processing unit" of his father's machine. In 1906, he successfully showed it printing the first 44 multiples of pi with 29 digits.

Cash registers

Further information: Cash registers

The cash register was invented by James Ritty in 1879. It was an adding machine with a printer, a bell, and a display that showed the amount of money for both the customer and the store owner. It was easy to use and became popular in many businesses.

Prototypes and limited runs

• In 1820, Thomas de Colmar patented the Arithmometer. He spent the next 30 years and a lot of money developing it. In 1851, he made a simpler version that could only add.
• From 1840, Didier Roth made a few calculating machines, including one based on Pascal's calculator.
• In 1842, Timoleon Maurel invented the Arithmaurel, which could multiply two numbers just by entering them.
• In 1845, Izrael Abraham Staffel showed a machine that could add, subtract, divide, multiply, and find square roots.
• Around 1854, Andre-Michel Guerry invented the Ordonnateur Statistique, a cylindrical device to help organize data about things like crime.
• In 1872, Frank S. Baldwin in the U.S. invented a pinwheel calculator.
• In 1877, George B. Grant in Boston began making the Grant mechanical calculating machine. It could add, subtract, multiply, and divide, and it was shown at the 1876 Centennial Exposition in Philadelphia.
• In 1883, Edmondson in the United Kingdom patented a circular stepped drum calculator.

1900s to 1970s

Mechanical calculators changed over time and had two main types of parts: moving back and forth, or turning in circles. The ones that moved back and forth were usually turned with hand cranks. The ones that turned in circles had parts that spun all the time.

In the early 1900s, a machine called the Dalton adding-listing machine was made. In 1948, a small handheld Curta calculator was created. From the 1900s to the 1960s, mechanical calculators were the main tools for math work on desks. Companies like Friden, Monroe, and SCM/Marchant in the USA made popular models. These machines could add, take away, multiply, and divide by repeating their moving parts. Some could also find square roots. Mechanical calculators were used a lot until electronic calculators replaced them in the 1970s.

Main article: History of computing hardware