William Morris Mordey (28 March 1856 – 1 July 1938) was a British electrical engineer and inventor who made important contributions the early electricity supply industry. A self-taught engineer from County Durham who later relocated to Bradford to continue working in Telegraphy, he became one of the practical pioneers of alternating-current engineering in Britain. His Mordey Victoria alternators were used at Bankside power station in the city of London (this site is now occupied by the Tate Modern) and at several other power station in Britain and abroad. He solved the problem of parallel alternator operation that made reliable public electricity supply possible, discovered the V-shaped alternator curves now known as V curve still taught today, and in 1889 proposed the ∿ symbol to denote AC periodicity (what is now known as hertz), writing "To save confusion I always write it thus, ∿ and I would suggest that this sign be used unless a better one be forthcoming…" The symbol was later formalised in British Standard BS 3939 Part 6 (from 1966) and internationally as IEC 60417 Symbol 5032 where it remains the standard graphical notation for alternating current worldwide.
Mordey was formally recognised in his lifetime. Serving as President of the Institution of Electrical Engineers, receiving an IEE premium for his work on alternating current, and winning the Telford Medal on a joint 1902 paper “Electrical Traction on Railways” with Bernard Maxwell Jenkin who received the George Stephenson Gold Medal. Mordey also filed 38 British patents, many of which also filed internationally. His work extended from alternators, dynamos, transformers and public electricity supply to electricity meters, railway electrification, electric ignition, electric heating, relays and electromagnetic mineral separation. By the time of his death in 1938, his reputation had faded, partly because the early technical history of electricity supply was "sadly neglected" and because Mordey himself published little about the difficulties he faced. His obituary in The Engineer described him as a pioneer whose work had scarcely received the recognition it deserved, and noted that few younger electrical engineers appreciated the importance of the Mordey Victoria alternator.
Family and early telegraph service
Mordey was born in Donnywell in County Durham on 28 March 1856. The Mordey family had been colliers and shipowners in Sunderland for several generations. William was the second son of John Goodchild Mordey and the grandson of Dr. William Mordey, a surgeon, magistrate and alderman who served multiple terms as Mayor of Sunderland, co-authored a medical account of the 1831 cholera outbreak, and helped establish the city's early public park and championed sanitary and cholera prevention measures.
At the age of fourteen, Mordey entered the postal telegraph service. After a short period in London he was transferred to Bradford. During this time, he devoted his spare time to the physics of telegraphy, relying entirely on his own resources as no tuition was obtainable. He later taught classes in telegraphy, magnetism, and electricity for the Science and Art Department and the City and Guilds of London Institute. In 1881 he sat the City and Guilds Institute examination alongside his own students and obtained the second prize and medal in the advanced stage of telegraphy.
Career
Brush Electrical Engineering (1881–1897)
At the end of 1881, Mordey left the telegraph service to join the Anglo-American Brush Electric Light Corporation (later the Brush Electrical Engineering Company). He became the company's chief electrician and focused on the design of alternating current (AC) and direct current (DC) dynamos, motors, and transformers.
The Mordey Victoria Alternator Mordey is best known for the Mordey Victoria Alternator, based on his 'spider-pole' design, which was designed and built with the Corporation's chief engineer John Smith Raworth. The British patent was GB5162, filed in 1888, with US437501A as an American equivalent.
The design differed significantly from other machines of the period. The magnet wheel, which contained a single coil, was designed so that the poles gripped around the thin disc-shaped armature winding in such a way that all poles on one side had the same polarity. The "Mordey Victoria" alternators played a significant role in the generation of single-phase current and the transition from gas lighting to electric lighting. These alternators, often paired with Raworth engines, were installed at many power plants across Britain and abroad.
Power station installations Mordey alternators and Raworth engines and switchgear were "as familiar to pioneer electrical engineers as Parsons' turbo-generators and Reyrolle switchgear are to those operating power stations at the present time." They were installed at stations across Britain. Among the most notable were Pandon Dene, Newcastle (1890), one of the first public power stations in Britain; Bankside, London (1891), which provided the first public AC electricity supply in London on the site now occupied by Tate Modern; and Lynmouth, Devon (1890), one of Britain's earliest hydroelectric installations, where a village that had never had a gas supply went directly from oil lamps to electric street lighting. A Wandsworth, London (1900), where six Raworth engines coupled to Mordey alternators supplied power distributed at 6,000 volts across substations serving south London.
Niagara Falls During the planning phase for the Niagara Falls power transmission scheme, Professor George Forbes publicly recommended the Mordey Victoria Alternators for the project in a Cantor Lecture at the Society of Arts on 8 February 1892, stating that "in connection with the Niagara scheme he had recommended synchronising alternate-current machines, the Mordey being specially mentioned." The contract was ultimately awarded to Westinghouse, whose generators used Nikola Tesla's polyphase rotating field system.
Great Northern Electric Light Station, Holloway In 1895, three Mordey Victoria alternators at a central generating station at Ashburton Grove, Holloway supplied electric lighting across the Great Northern Railway's main line out of London, a scheme The Engineer described as pioneering. Contemporary recognition and high-frequency alternators In 1892 Nikola Tesla referred to a "machine of the Mordey type," explaining that this as a machine with pole projections of the same polarity. Tesla added that, with few projections and "an armature without iron, as used by Mordey," excellent results had been obtained.
Mordey was also credited in American technical literature. T.C Martin and Joseph Wetzler's The Electric Motor and its applications credited Mordey with first pointing out an important practical precaution concerning iron cores and motor efficiency. Later, J. A. Fleming connected the Mordey type to wireless work, writing that Fessenden, "like Tesla," adopted the Mordey type of alternator for high-frequency generation.
Legacy in wireless telegraphy
The disc-armature design of the Mordey alternator found direct application in wireless telegraphy. When Canadian radio pioneer Reginald Fessenden constructed the high-frequency alternator used for the world's first radio broadcast on Christmas Eve 1906, transmitting voice and music from Brant Rock, Massachusetts to ships at sea, IEEE historian John S. Belrose described it as "a small machine of the Mordey type, having a fixed armature in the form of a thin disc, or ring, and a revolving field magnet with 360 teeth, or projections," generating 50,000 Hz at 139 revolutions per second.
Fessenden subsequently commissioned Ernst Alexanderson at General Electric to develop a higher-powered machine, which became the Alexanderson alternator used at Marconi's transatlantic wireless stations.
Consulting work
After leaving Brush in 1897, Mordey went on to work as a consulting engineer in London. By 1898 he was operating from 82 Victoria Street. He entered a partnership with Robert Arthur Dawbarn to form Mordey and Dawbarn. In August 1902 Mordey and Dawbarn were appointed as engineers for the extension of the Johannesburg power station, the construction of electrical tramways and lighting for Pretoria, electrification of the railway from Springs to Randfontein. In 1905 they provided advice on the Johannesburg telephone system, and during 1905-1906 reported on the supply of electricity to government departments in Durban.
During this period Mordey also developed the Mordey-Fricker electricity meter with Guy Carey Fricker, exhibited at the Royal Society and described in The Engineer as a new and simple meter suitable for direct or alternating currents Recognition and institutional work Mordey co-authored "Electrical Traction on Railways" with Bernard Maxwell Jenkin. The paper examined direct and alternating current methods of railway electrification, with the authors making the case for single-phase alternating current traction. Lord Kelvin praised the authors for attacking the problem of long lines and for their case for single phase alternating current traction. Mordey received the Telford Medal and Jenkin received the George Stephenson Gold Medal.
Mordey also received honourable mentions from the Council of the Society of Telegraph Engineers for his 1883 paper "Some Prejudicial Actions in Dynamo Machines." He was a member of the council of the Institution of Electrical Engineers from 1890 to 1894. For his contribution on AC working, including the construction of an alternator for parallel working, he received the IEE Premium - the Institution's annual award for the most valuable contribution of the year.
He was named to the British Electrical Committee for the 1893 Chicago Exhibition alongside Lord Rayleigh, Sir William Thomson and Major-General C. E. Webber.
in 1908 he became the President of the Institution of Electrical Engineers. His Inaugural Address compared the British and German electricity supply industries and called for greater government engagement with industrial electrical policy.
Following Silvanus P. Thompson death in June 1916, Mordey, who had been a long-standing friend to Thompson, chaired the committee that acquired Thompson's scientific library for the IEE, serving as one of four trustees and delivering the formal presentation address at the 51st Annual General Meeting in 1923.
The 1889 IEE paper: On Alternate-Current Working
On 23 May 1889, Mordey presented "On Alternate-Current Working" to the Institution of Electrical Engineers. The paper was presented to an audience containing John Hopkinson, William Ayrton, John Ambrose Fleming, Gisbert Kapp, Sebastian Ferranti, Silvanus P. Thompson, W.H. Preece FRS, and John Smith Raworth. The discussion was so significant that a second meeting was convened on 30 May 1889, with the discussion running to 44 pages.
The paper covered six distinct areas: parallel working of alternators, AC motor systems, the ~ symbol and frequency standardisation, conductor skin effect analysis, electrical safety, and hysteresis and eddy current separation.
The 1893 IEE paper: On Testing and Working Alternators
On 23 February 1893, Mordey presented "On Testing and Working Alternators" to the IEE, chaired by W.H. Preece FRS. The paper introduced testing methodology for alternators in service, the Equaliser device for eliminating circulating currents in parallel windings, a six-principle system for parallel working, and the V curve.
Technical contributions
Parallel working of alternators One of the fundamental problems of early AC supply was running alternators in parallel. In simple terms, this meant connecting more than one alternator to the same supply network so that they shared the electrical load. If badly controlled, alternators could hunt, fall out of step or destabilise the supply.