mechanical calculator
A mechanical calculator, or calculating machine, is a mechanical device used to perform the basic operations of arithmetic automatically, or a simulation like an analog computer or a slide rule. Most mechanical calculators were comparable in si ...
Berlin
Berlin ( ; ) is the Capital of Germany, capital and largest city of Germany, by both area and List of cities in Germany by population, population. With 3.7 million inhabitants, it has the List of cities in the European Union by population withi ...
,
Germany
Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...
. Variants of it were manufactured from 1920 until 1982. The devices were made obsolete by the
electronic calculator
An electronic calculator is typically a portable Electronics, electronic device used to perform calculations, ranging from basic arithmetic to complex mathematics.
The first solid-state electronic calculator was created in the early 1960s. ...
.
Design
The Addiator is composed of sheet-metal sliders inside a metal envelope, manipulated by a stylus, with an innovative carry mechanism, doing ''subtract ten, carry one'' with a simple stylus movement. Some types of Addiators can also handle negative numbers (with a complementary bottom window or by providing a subtraction mode on the back side of the device).
The Addiator also handles non-decimal measurements, like feet and inches, or pre-decimalization pounds, shillings, and pence. Addition and subtraction require different "screens", handled by turning the instrument over, or flipping a front panel, or, later, by extended sliders and an extra lower panel. Although not always advertised (e.g., the Magic Brain Calculator mentions "add, subtract, multiply" on its front plate), procedures exist for multiplication (by repeated addition or by individual digit multiplications) and division (e.g., by repeated subtraction, or use of additions combined with complementary numbers).
More expensive versions have a built-in
slide rule
A slide rule is a hand-operated mechanical calculator consisting of slidable rulers for conducting mathematical operations such as multiplication, division, exponents, roots, logarithms, and trigonometry. It is one of the simplest analog ...
on the back.
History
Sometime between 1666 and 1675, French polymath
Claude Perrault
Claude Perrault (; 25 September 1613 – 9 October 1688) was a French physician and amateur architect, best known for his participation in the design of the east façade of the Louvre in Paris.rabdological
abacus
An abacus ( abaci or abacuses), also called a counting frame, is a hand-operated calculating tool which was used from ancient times in the ancient Near East, Europe, China, and Russia, until the adoption of the Hindu–Arabic numeral system. A ...
), when he needed to do a lot of calculations while working as an
architect
An architect is a person who plans, designs, and oversees the construction of buildings. To practice architecture means to provide services in connection with the design of buildings and the space within the site surrounding the buildings that h ...
.
About three decades later, around 1700 or shortly after, French businessman and amateur mathematician César Caze simplified Perrault's design and adapted it to counting money, getting a privilege (patent) in 1711. However, neither of these devices implemented a carry mechanism.
In 1845, German musician and amateur mechanic Heinrich Kummer, who was living in St. Petersburg, saw a mechanical calculator of a different design made by
Hayyim Selig Slonimski
Ḥayyim Selig ben Ya'akov Slonimski (; March 31, 1810 – May 15, 1904), also known by Hebrew abbreviations, his acronym ḤaZaS (), was a Hebrew publisher, mathematician, astronomer, inventor, science writer, and rabbi. He was among the first t ...
, and in the next year borrowed the idea of its carry mechanism to greatly improve Caze's device, leading to the modern variant of the slide calculator.
Addiator
In 1889, Louis-Joseph Troncet successfully commercialized the Addiator, which became one of the most popular calculators of its kind, and the name is often used to refer to the type generally.
Addiators appeared in newspaper advertisements as early as 1921, listed at a price of in the '' Daily Record'' of Scotland. As of 1968, Addiators were advertised in American newspapers starting at $3.98 each .
YouTube
YouTube is an American social media and online video sharing platform owned by Google. YouTube was founded on February 14, 2005, by Steve Chen, Chad Hurley, and Jawed Karim who were three former employees of PayPal. Headquartered in ...