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Chebyshev. Later on the french historian Maurice d’Ocagne contacted Chebyshev for description of the machine
and published an article.
In fact, both machines of Chebyshev were made only for demonstration purposes. He never seriously thought of
creating a device for practical or commercial use. His personal innovations are continuous tens carry and auto-
matic shifting of the carriage from decimal place to decimal place during multiplication. Both inventions became
popular and were widely implemented in 1930s, when electromotive drives came into use in the quickly growing
generation of automatic and semi-automatic keyboard calculating machines.

Odhner arithmometer
W. Theophil Odhner invented his mechanical calculator in 1873 in Saint Petersburg. He
built 14 machines for Ludvig Nobel, his employer at the time, then patented it in several
countries and started serial production in 1890. The arithmometer became one of the
most successful type of mechanical calculator ever designed with millions sold in 19th
and 20th centuries. In 1924, the Soviet government moved the old production facility to
Moscow and commercialized their calculator under the Felix Arithmometer name which
went on well into the 1970s. Odhner’s arithmometer was copied, manufactured and sold
by many other companies all over the world. It was recognized that, by the end of the
1940, the Odhner arithmometer was the most popular portable mechanical calculator in
W . Theophil Odhner the world.
(1845–1905) Willgodt Theophil Odhner was born in 1845, in Dalby, Värmland, in central Sweden.
Odhner studied mechanics and mechanical technology at the Royal Institute of Technol-
ogy in Stockholm, but although he completed his third year he never finished his study. Finding employment in
Sweden was difficult in those times and in 1868 Odhner moved to St. Petersburg in Russia where he found a job
iworking for fellow-countryman Ludvig Nobel – the older brother of the famous Alfred Nobel.
Odhner must have seen (possibly brought in for some repair) or have read about the Thomas de Colmar arith-
mometer which was designed in 1822. He thought that he could design a better and more efficient calculating
machine. His solution was based on a geared pinwheel mechanism and resulted in the well-known barrel-shaped
calculating machines bearing his name. It was ready for demonstration in 1875. In 1878 he submitted an applica-
tion for the patent on his invention to the United States Patent Office which was awarded three months later; this
was soon followed by patents in other countries.
Fortunately Nobel saw the merit of the Odhner machine and asked
him to produce 14 machines. He also gave Odhner some space in his
factory for the manufacture of these machines and he agreed to carry
the costs as well as paying Odhner a salary. The two men agreed they
would later split the profits of this endeavour. Although the first mod-
el carried only 9-digit results, the next version could handle 10-digit
answers and this increased
to 11 digits by 1889. The
machine had three regis-
ters: one to manually set the
multiplicand, one to reg-
The Odhner arithmometer of 1890 ister the result and one to
count the revolutions of the crank (i.e. the multiplier). For each manual
revolution of the crank the multiplicand would be added to the results
register, while the revolution register kept track of the number of revo-
lutions. After having done one decimal position the carriage was shift-
ed one position to the left for the next decimal. Clearing of the registers
took place through the use of wing-nuts on either side of the carriage
on earlier models, clearly visible in above illustration. In later models
the wing-nuts were replaced by crank handles.
In 1886 Odhner founded the W.T. Odhner, Maschinenfabrik & Metall-
giesserei in St. Petersburg for the manufacture of his calculators. The
design Odhner Paten proved quite reliable and the machine was easy
to handle. The patent drawings of Odhner’s 1879

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