Alfred Graham & Co
Little is known of this British company or its history. It appears to have started in the early days of telephony, in the late 1880s, as a partnership between Alfred Graham, Edward Alfred Graham, and Joseph Arthur Lovel Dearlove. Arthur Dearlove (1858 - 1923) appears to have been the technical man, with patents for telegraphy in his name. He went to the Seychelles, Mauritius and Zanzibar from 1893 to 1898 as an assistant engineer with Clark, Ford and Taylor to work on cable laying. He later became a partner, then owner, of this firm. The partnership with the Grahams broke up in 1916. The factory at Halifax developed a niche market for ship's phones, and produced some very distinctive telephones. Even these are not well known, mostly from details in resellers' catalogues and histories of the ships equipped with Alfred Graham phones.
The first patent known in Graham's name is a Canadian one dated 1927. By this time the design of his phones had been well established. Marine telephones have characteristics that make them different from ordinary phones. They operate in an environment that has constant vibration from the engines. The atmosphere is corrosive, either from salt in the air of from ash or coal dust in the boiler rooms. The power supply may be irregular. Some will be fitted in noisy engine rooms. In the case of telephones for warships the telephone had to be able to work under battle conditions and in spite of damage. Traditionally these requirements were met with speaking tubes, so Graham's phones must have been exceptionally well designed to replace them.
They were mostly made in heavy brass, beloved of marine engineers because surface corrosion could be controlled by regular polishing. It was easy to machine with precision, allowing parts to be closely fitted to block the entry of salt air into the electrical parts. The parts that had to be open to the atmosphere were carefully filtered. The phones used large diaphragms to give the highest possible sound levels. The receivers for phones in noisy locations were fitted with trumpets (called "side arms" by Grahams) to reduce background noise. Buzzer signaling was preferred because a buzzer had fewer moving parts than a bell, but the bells and buzzers could be tuned to different frequencies for locations where there was more than one phone.
1928 patents describes the workings of a typical phone. The filters on the mouthpiece consist of fine brass mesh and waterproofed cloth. The diaphragm is a Graham innovation, a composite sandwich of elastic materials with a metallic diaphragm between them. The diaphragm is damped by a set of metal fingers in various configurations, depending on the characteristics needed. With careful damping the diaphragm can be used as transmitter and receiver, giving some of the phones their characteristic drum shape. Some receivers were so sensitive that the phones were called loudspeaking telephones, and could be heard up to twenty feet away.
Left: 1928 transmitter. Note the massive magnet (about 3 inches across)
and large diaphragm.
Left: Exploded view of composite diaphragm
To overcome the unreliability of shipboard power supplies, Graham returned to Bell's original transmitter, the electrodynamic model. In this, the movement of the diaphragm generated a current in a coil held in a magnetic field. For Bell's purposes, the transmission range was too limited although the signal strength was quite adequate over short distances. For Graham's purposes, the limited transmission distance on a ship perfectly suited this type of transmitter. These became known as "sound powered telephones" and their reliability made them a preferred option for warships, where battery power could be cut off by battle damage. In 1898 Graham telephones were adopted by the British Navy.
With the extended movement of the large diaphragms, the signal could drop as the diaphragm moved out of the magnetic field. To overcome this, Graham attached the coil to the diaphragm directly in some models. This arrangement had been tried by Edison, but was dismissed because it made the transmitter bulky and less sensitive. In Graham's phones, the bigger diaphragm overcame the sensitivity problem, and the bulk was not a problem because the phones were wall mounted.
The company's best years were between 1900 and 1920 when the construction of large liners and warships took off. Many famous ships were equipped with Graham's Navyphones, such as the Olympic and Titanic, Britain's Dreadnought class of battleships, and the new Australian Navy's heavy cruiser HMAS Australia. Phones in the liners' cabins were optionally silver plated. A new factory at Brackley in 1911 helped meet the demand. Their telephones were selling internationally, marketed by firms like Sterling Telephone and Electric and GEC. In 1919 they proudly claimed " no less than 12,000 ship installations made". They also appear to have been selling phones to the British Post Office, who allotted them the manufacturer code CH.
By the end of World War 1 the company was in a good financial position, but facing a reduction in its market. Treaties reduced the number of warships. Those that remained in service would not need re-outfitting for many years. The passenger trade was mostly satisfied by existing ships. A new direction was needed. The head office moved to Caxton House, Tothill Street, London in 1924.
From the early 1920s a new company, Graham Amplion, marketed a wide range of Amplion loudspeakers, benefiting from their knowledge of acoustics in telephones and marine public address systems. They also built gramophones under the Aigraphone name, and sold Metrovic radio valves for the new growth industry, wireless. Eventually they marketed their own Amplion wireless receiver. A new factory was proposed at Perry Hill in London in 1927, but for unexplained reasons it did not proceed. Marketing companies were set up in the United States and Canada to market the company's products. The Amplion name was still being attached to portable transistor radios into the 1960s when the company was finally taken over (by GEC?) in the face of falling sales from cheaper imports.
Marine telephones continued through this period. Three new names share the patents of this period - E E Smith, Cyril Hugh Vaughan, and Maria Graham. Again, nothing is known of them, but their patents continue the development of shipboard communications systems.
With the outbreak of the Second World War the company's fortunes could have changed, but they seem to have lacked direction and they limped through the war rather than powered through it. Partly this was because sales to the large foreign navies were now being taken over by firms like Stromberg Carlson, who supplied much of the U.S. fleet.
The end of the war also marked the end of the company.
Research supplied by Alan Gall
The Dreadnought Project website at http://www.dreadnoughtproject.org/docs/notes/Torpedo_Drill_Book_1914.php