Arvid Gerhard Damm
Encyclopedia
Arvid Gerhard Damm was a Swedish
engineer and inventor. He designed a number of cipher
machines, and was one of the early inventors of the wired rotor
principle for machine encipherment. His company, AB Cryptograph, was a predecessor of Crypto AG
.
Damm was originally a textile
engineer, and worked as an engineering manager in a textile factory in Finland
. At this time, he faked a marriage to a Hungarian woman in a sham ceremony conducted by one of Damm's friends posing as a clergyman. Later, after having found a new romantic interest, Damm attempted to "divorce" her, accompanied by false allegations that she was a spy, and was greatly embarrassed when his duplicity emerged during the case, revealed by business partner Olof Gyldén (who was subsequently passed over for promotion at Damm's company).
Damm filed for a patent (Swedish patent #52,279) on a rotor machine on 10 October 1919, three days after Hugo Koch
filed a patent for a similar invention in the Netherlands
. A company, Aktiebolaget (AB) Cryptograph, was founded around 19151 to sell and develop Damm's inventions.
In 1925, engineer Boris Hagelin
was placed in charge of the management of the company and the development of its products, having joined AB Cryptograph in 1922. Damm died in early 1927.
Damm's machines included the "Mecano Cryptographer Model A-1" model and its interoperable portable counterpart, Model A-2. The A-1 was fitted with a keyboard, and printed the plaintext together with two copies of the plaintext onto tape. The machine used a chain of links, which could be reassembled by the user as part of the key
. Some of the links moved a 25-disk "key body" forward, some back.
Another model, the A-21 (from 1915), was described by Hagelin as Damm's "first fundamentally sound machine" (Hagelin, 1994). The A-21 consisted of a cylinder with 26 mixed alphabet strips around it. Another strip, bearing the normal A–Z alphabet was nearby, and could take one of two positions, dependent on the movement of chain similar to the A-1. In operation, the cylinder rotated one step, as did the chain, controlling the position of the reference alphabet. To encipher or decipher (the system was set up to be reciprocal), a letter could be read off from the reference alphabet to a cylinder alphabet using a slit at the top of the machine. This model was also available in a larger "office" model equipped with a keyboard.
A later machine was the B-1, which was used by Sweden's telegraph service. The B-1 underwent tests in France in 1925, but proved to be unreliable in operation.
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
engineer and inventor. He designed a number of cipher
Cipher
In cryptography, a cipher is an algorithm for performing encryption or decryption — a series of well-defined steps that can be followed as a procedure. An alternative, less common term is encipherment. In non-technical usage, a “cipher” is the same thing as a “code”; however, the concepts...
machines, and was one of the early inventors of the wired rotor
Rotor machine
In cryptography, a rotor machine is an electro-mechanical device used for encrypting and decrypting secret messages. Rotor machines were the cryptographic state-of-the-art for a prominent period of history; they were in widespread use in the 1920s–1970s...
principle for machine encipherment. His company, AB Cryptograph, was a predecessor of Crypto AG
Crypto AG
Crypto AG is a Swiss company specialising in communications and information security. With headquarters in steinhausen, the company is a long-established manufacturer of encryption machines and a wide variety of cipher devices...
.
Damm was originally a textile
Textile
A textile or cloth is a flexible woven material consisting of a network of natural or artificial fibres often referred to as thread or yarn. Yarn is produced by spinning raw fibres of wool, flax, cotton, or other material to produce long strands...
engineer, and worked as an engineering manager in a textile factory in Finland
Finland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...
. At this time, he faked a marriage to a Hungarian woman in a sham ceremony conducted by one of Damm's friends posing as a clergyman. Later, after having found a new romantic interest, Damm attempted to "divorce" her, accompanied by false allegations that she was a spy, and was greatly embarrassed when his duplicity emerged during the case, revealed by business partner Olof Gyldén (who was subsequently passed over for promotion at Damm's company).
Damm filed for a patent (Swedish patent #52,279) on a rotor machine on 10 October 1919, three days after Hugo Koch
Hugo Koch
Hugo Alexander Koch was a Dutch inventor who conceived of and patented an idea for machine encryption — the rotor machine, although he was not the first to do so...
filed a patent for a similar invention in the Netherlands
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...
. A company, Aktiebolaget (AB) Cryptograph, was founded around 19151 to sell and develop Damm's inventions.
In 1925, engineer Boris Hagelin
Boris Hagelin
Boris Caesar Wilhelm Hagelin was a Swedish businessman and inventor of encryption machines.Born of Swedish parents in the Caucasus , Hagelin attended Lundsberg boarding school and later studied mechanical engineering at the Royal Institute of Technology in Stockholm, graduating in 1914...
was placed in charge of the management of the company and the development of its products, having joined AB Cryptograph in 1922. Damm died in early 1927.
Damm's machines included the "Mecano Cryptographer Model A-1" model and its interoperable portable counterpart, Model A-2. The A-1 was fitted with a keyboard, and printed the plaintext together with two copies of the plaintext onto tape. The machine used a chain of links, which could be reassembled by the user as part of the key
Key (cryptography)
In cryptography, a key is a piece of information that determines the functional output of a cryptographic algorithm or cipher. Without a key, the algorithm would produce no useful result. In encryption, a key specifies the particular transformation of plaintext into ciphertext, or vice versa...
. Some of the links moved a 25-disk "key body" forward, some back.
Another model, the A-21 (from 1915), was described by Hagelin as Damm's "first fundamentally sound machine" (Hagelin, 1994). The A-21 consisted of a cylinder with 26 mixed alphabet strips around it. Another strip, bearing the normal A–Z alphabet was nearby, and could take one of two positions, dependent on the movement of chain similar to the A-1. In operation, the cylinder rotated one step, as did the chain, controlling the position of the reference alphabet. To encipher or decipher (the system was set up to be reciprocal), a letter could be read off from the reference alphabet to a cylinder alphabet using a slit at the top of the machine. This model was also available in a larger "office" model equipped with a keyboard.
A later machine was the B-1, which was used by Sweden's telegraph service. The B-1 underwent tests in France in 1925, but proved to be unreliable in operation.
Patents
The following patents were issued to Damm in the United States: — "Apparatus for Producing a Series of Signs", filed 21 July 1915, patented 10 July, 1917 — "Apparatus for Ciphering and Deciphering Code Expressions", filed 25 March, 1922, patened 19 February, 1924. — "Production of Ciphers", filed 2 April, 1920, patented 22 July, 1924. (Equivalent to Swedish patent 52,279). — "Apparatus for the Production of Cipher Documents Especially For Telegraphic Dispatch", filed 1 March, 1922, patented 2 June, 1925. — "Apparatus for Producing a Series of Signs", filed 25 September, 1924, patented 4 October, 1927. Filed in Sweden 28 September, 1923. — "Electric Apparatus", filed 31 August, 1925, patented 27 March, 1928.See also
- Edward HebernEdward HebernEdward Hugh Hebern was an early inventor of rotor machines, devices for encryption.-Background:Edward Hugh Hebern was born in Streator, Illinois on April 23, 1869. His parents were Charles and Rosanna Hebern. They met in Harris County, Texas while Charles was serving as guard and escort from the...
- Arthur ScherbiusArthur ScherbiusArthur Scherbius was a German electrical engineer who patented an invention for a mechanical cipher machine, later sold as the Enigma machine.Scherbius was born in Frankfurt am Main and his father was a small businessman...