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Britannic

Britannic

The Britannic is a pinwheel calculator made in the United Kingdom. It has a 9-digit input without a display register. The carriage at the front holds an 18-digit register with an 10-digit counter to its left. The counter does not have a carry mechanism. Turning the crank on the right of the machine clockwise will add the input to the register, and turning it anti-clockwise subtracts the input from the register. The metallic mechanism on the front of the carriage is used to shift the carriage one step to the right or left, and when holding the knob down the carriage can be moved any amount. To the left of the input levers is a lever that resets the input to zero. The wingnuts on the left and right ends of the carriage reset the counter and register to zero respectively.

It is mounted on a wooden base, with a wooden case cover. Unfortunately the fittings in the cover are missing so it no longer attaches to the base, and cannot be locked. It is also missing the knob on the clearing mechanism. It is possible that these were all removed to be melted down for the war effort.

The serial number is 1462, which makes this a fairly early machine. It is not clear exactly when it was made, but probably the late 1920s or early 1930s. The number on the rear cover plate of my machine was struck very badly. The 4 is sideways, and the 2 was first done upside down, and then half-struck the right way up. The number can also be found on the back of the carriage near the register's units wheel, and on the base frame just behind the rear cover.

Video

History

Frank Edward Guy worked as an insurance clerk where he became very familiar with calculators, and in 1909 he even patented an improvement to them. In the next few years of the 1910s he was importing and selling calculators, in particular Mercedes-Euklid machines. While the First World War was raging it became impossible to import new calculators from Germany, so he decided to develop and manufacture his own pinwheel calculator. He got financial backing from the B.P. and Anglo-Persian Oil Company, under the condition that he would supply them with the calculators they needed first, though he was free to sell any surplus to other customers. He founded Guy's Calculating Machines Ltd in August 1918, or shortly before. It was located at Truro Works, 12 Truro Road, Wood Green, London N22. It seems to have been a very small production for many years, with just 2000 units in 15 years. By about 1923 the machines were appearing on the general market, and sold through various supply companies, such as Remington Typewriters, and later Muldivo.

Muldivo was a company founded in 1912. They imported calculators, and sold them usually rebranded as Muldivo calculators. They first imported Chateau pinwheel calculators from France, then Thales machines from Germany, and finally Walthers. In the 1930s they also distributed the Britannic, and in about 1939 they bought Guy's Calculating Machines, probably to secure a domestic source of calculators during the coming war. Production then increased for a while.

After the war, Guy's Calculating Machines slowly began to turn into a general precision engineering company, as Muldivo resumed importing and selling calculators from Switzerland and Germany (e.g. Madas, Walther). In 1965, Guy’s moved to Witham in Essex, and was sold off by Muldivo in 1969. By this time Muldivo was struggling to deal with the arrival of electronic calculators, and and finally dissolved in 1971.

Models

For a long time there was essentially only one model - large capacity (18-digit register) and no carry in the counter. There were minor variations in the size of the input, (9 to 12 input pins). It seems that it was only after Muldivo bought Guy's Calculating Machines that more models appeared - small or large capacity (labeled 1 or 2 respectively), and with or without carry in the counter register (B and A respectively). Later still, an input display register (T) was added. The original model is retroactively a model 2A.

In the second world war the British Army needed calculators with two registers like the Brunsviga D 13Z for doing coordinate calculations. The Brunsviga, being German made, was obviously no longer readily available. The Britannic Duo was made for that purpose, but was deemed not reliable enough, so the army instead built double calculators from Marchant XL machines. The Britannic Duo is therefore very rare.

Here is a table of all the Britannics that I have found online:

Advertisements and Articles

Here are some ads for the Britannic.

Here are various short descriptions and mentions of the Britannic in books and magazines.

Various other related tidbits. These include mentions of Frank E. Guy in ads or articles, as well as the announcement of the founding of Guy's Calculating Machines, and an ad by Block & Anderson.

Patents

Links

• Vintage Calculators Web Museum has a Britannic page that includes the Duo.
• Cris Vande Velde has various Britannics, namely models 2A, 1B, 2B, and Duo.
• Rechenmaschinen-Illustrated has some pictures of Britannic calculators.
• The Arithmeum has a Britannic 2A and a Britannic 2B.
• Rechner Lexicon has a page for the Britannic.
• Rechnen Ohne Strom has a Britannic 2A.
• John Wolff's Web Museum has a Britannic 2A.

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