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Theo Reumerman was born in Utrecht, The Netherlands, in 1899. In the 1930's Theo worked in the Dutch East Indies, now Indonesia. There he developed a 14-digit telegraph code in 1933 [SOE1933], a Multi-cipher-code condensor in 1934[SOE1934], and, in 1937, a 3-letter telegraph code called "M.E.C." (Most Economical Code). This code should save 25% of the costs of the usual 5-letter telegraph code.[NAC1937]
In 1938 he travelled to The Hague, The Netherlands, to establish a Dutch branch of his telegraph code business. Later, while living in Zandvoort, The Netherlands, he met Willem Helmig. In 1948 they presented a mechanical checksum-device, especially aimed at telephone numbers[Reumhelm1948]. At that time, Dutch local telephone numbers consisted of 5 digits. The idea was to add a sixth check-digit which was checked by the telephone itself. The telephone would block a call if the number was wrong. This local check would reduce the load of telephone exchanges without having to adapt them. Other applications were listed, like bank-note numbering, telegraphy, printing, gas meters and “general industrial use”.
An invention[US2722378] that was actually marketed is the Controlex, a device for casting out elevens.
Figure 1: Reumhelm Controlex [Reumhelm1953] (left) and a reconstruction (right).
Figure 2: Controlex advertisement [SC1953]
Try the interactive simulation of this device
Reumerman and Helmig also patented a device with stepped drums for checksums with arbitrary weights per digit (Figure 3) but did not restrict themselves to purely mechanical checksum devices.
They patented a checksum calculator with rotors bearing electrical contacts, conducting brushes and indicator lamps for simultaneously checking modulo 9 and modulo 11 (Figure 4).
Who sold the Controlex?
Who sold the Controlex?
Left to right: Th. Reumerman, W.H.Th. Helmig, J.H. Breedenbeek [Telegraaf1953]
According to the “Kantoormachinegids” [Reumhelm1953], the official seller of the Controlex was NV G. Kolff & Co, a Dutch office supplier with Indonesian roots, who was also an national importer of Monroe calculating machines[Harkink].
In 1953 and 1954, a series of small advertisements appeared mentioning “Bredenbeek, Westerscheldeplein 1, Amsterdam” as seller of the Controlex or an “American calculating aid” with the same price as the Controlex[Bredenbeek]. A 1953 newspaper article [Telegraaf1953] says that J.H. Breedenbeek(sic!) was sales officer for Reumhelm.
Did Bredenbeek sell the Controlex under his own name?
(Note: G. de Jong in Figure 2 is a local office supplier)
Figure 3: Checksum device with arbitrary weights per digit (Canadian Patent 541,633; 1957)
Figure 4: Checksum device with rotors, brushes and lamps (US Patent 2,684,199; 1951)
Other Reumhelm patents describe relay-based checksum calculators, a telephone-operated remote banking system (with checksums) and character-reading devices.
The name and legal status of Reumhelm SA is unclear. A 1951 advertisement mentions Reumhelm AG, established in Vaduz, Liechtenstein, but with the private address of Helmig in Leiden[AH1951]. According to a 1953 newspaper[Telegraaf1953], the company was established in Panama and Liechtenstein, and the Controlex was also sold in the USA and South Africa. Around 1955 the name “Reumhelm Electronics NV” appears. Representations existed in (at least) Switserland.
Zuse KG showed some interest in Reumhelm's inventions[Zuse], as did Remington Rand[Remington] and Landis & Gyr [ETH].
By 1953, Reumhelm held 124 patents[Telegraaf1953]. Bell Punch Comp., Sumlock Ltd, British Tabulating Machines, Siemag, Dirks-Electronics, Zuse, Landis & Gyr, and N.V. Procento are listed as Reuhelm patent licencees in 1955[Zuse]. Some Reumhelm patents mention Remmer W. Starreveld as inventor. Starreveld was editor of the “Kantoormachinegids” and later became professor of Information Technology at the University of Amsterdam. Other names that appear on Reumhelm patents are Cornelis Adrianus Meijer and Cornelis Adrianus Simon Hamelink.
Theo Reumerman died in 1969 [ZC1969]. Around that time the Reumhelm company also ceased to exist.
References
References
[SOE1933] Soerabaijasch handelsblad, December 13, 1933, page 6 . The code book was self-published.
[SOE1934] Soerabaijasch handelsblad, February 7, 1934, page 2.
[NDN1937] Het nieuws van den dag voor Nederlandsch-Indië, April 17, 1937, page 7. The code was publised as: Th. Reumerman, "M.E.C.; Most Economical Code, 3-letter code", De Unie, Batavia, 1937; New York, 1938
[Reumhelm1948] De Heerenveensche Koerier, December 9, 1948, page 1; December 11, 1948, page 5; Dagblad voor Amersfoort, December 11, 1948; Nieuwe Courant, Decembe 20, 1948, page 3.
[US2722378] W.H.T. Helmig, Th. Reumerman, “Means for determining check symbols for symbol groups,” US Patent 2,722,378, filed March 6, 1951, published November 1, 1955.
[SC1953] Advertisement in Stichtsche Courant, June 5, 1953, page A2; August 29,1953 page A164; September 4, 1953, page A150. For 2.50 Dutch Guilders one could also buy a pair of cheap nylon stockings in 1953.
[AH1951] Advertisement in Algemeen Handelsblad, January 31, 1951, page 6.
[Telegraaf1953] De Telegraaf, August 8, 1953, page 11.
[Reumhelm1953] Controlex entry in “Kantoormachinegids,” August 1953, preface and section 3-1, see also Rechnerlexikon
[Harkink] F. Harkink, "Inleiding tot het praktisch rekenen", 2nd ed., P. Noordhoff, 1949, page 193.
[Bredenbeek] Advertisements in De Telegraaf: October 31, 1953, page 21 (“American”); February 20, 1954, page 14; February 27, 1954, page 10; March 6, 1954, page 10
[Zuse] Deutsches Museum, Archiv; NL 207 Zuse: Reumhelm. (esp. NL 207/0617; NL 207/0618; NL 207/0620; NL 207/0621; NL 207/0823; NL 207/0983; NL 207/1880. The latter is a 1955 letter that was sent to licensees of Reumhelm patents: Bell Punch Comp., Sumlock Ltd, British Tabulating Machines, Siemag, Dirks-Electronics, Zuse, Landis & Gyr, N.V. Procento. It describes a decision to use base-13 checksums)
[Remington] C.A. Norton, “Report on the Reumhelm patent and Remington's Check Digit Verifier,” Remington Rand Univac, March 20, 1961 (draft) in: papers of George Stibitz
[ETH] ETH Zürich Archiv für Zeitgeschichte, Landis & Gyr F-108-000.
[ZC1969] Zandvoortse Courant, August 8, 1969, page 2
Th. Reumerman, W.H.Th. Helmig (Reumhelm Electronics N.V.), "Automatic Symbol-Group Repetition Corrects Transmission Errors", electronics, 34(39) Sep 29, 1961, page 146-148
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