Grace's Guide To British Industrial History

Registered UK Charity (No. 115342)

Grace's Guide is the leading source of historical information on industry and manufacturing in Britain. This web publication contains 163,139 pages of information and 245,599 images on early companies, their products and the people who designed and built them.

Grace's Guide is the leading source of historical information on industry and manufacturing in Britain. This web publication contains 147,919 pages of information and 233,587 images on early companies, their products and the people who designed and built them.


From Graces Guide
Plaque on the Winding Gear on the Victory Shaft at Geevor Mine.
Electric Winding Equipment at Geevor Mine.
Winding gear for the Victory Shaft at Geevor Mine.
June 1898.
Exhibit at the Dover Transport Museum.
1912. Curtis Turbines.
November 1922.
1922. Electrical Equipment for a Scherbius Rolling Mill.
1924. Colliery winding equipment.
1929. The Rugby Works of the British Thomson-Houston Company Ltd.
December 1929.
December 1929.
December 1929.
December 1929.


May 1930.


August 1933. Fabroil.
March 1934.
February 1936. Flame-proof metal-enclosed switchboard.
6th January 1939.
15th December 1939.
Film projector. Exhibit at Abbey Pumping Station, Leicester.
Film projector. Exhibit at Abbey Pumping Station, Leicester.


April 1943.
November 1943
May 1944.
June 1944.
1944. Outdoor Oil Circuit Breaker.
April 1945.
August 1945. For the Bristol Engine Co: Centaurus.
October 1945.




November 1946. Flameproof Switchgear.
April 1947. Fabroil silent gears.
1947. BTH Switchboard. 220 VDC. Exhibit at Internal Fire Museum of Power.
November 1947.
January 1948.
March 1948.
May 1948.
May 1950.
November 1950.
December 1950.
1950. Heavy Plant Building at Rugby.
October 1951.
January 1952.
March 1952.
May 1952. 'Fabroil' silent gears.
June 1953. Marine Propulsion and Radar Equipment.
1953. Horizontal Boring and Milling Plant.
1953. Large boring mill.
Sept 1953.
1955. 401 Film Projector.
1955. Lighting the parade at Leamington Spa.[1]
1955. Lighting in the factory of Brynmawr Rubber.
1956. Film Projector.
March 1958.
1959. Education Building of the British Thomson-Houston Co. Rugby.
Type 249. Detail. Exhibit at National Waterways Museum, Gloucester.
Electricity meter.
Sound Reproducer Type S.R.B.
Sound Reproducer Type S.R.B.
Sound Reproducer Type S.R.B.

British Thomson-Houston Co (BTH) was a British engineering and heavy industrial company, known primarily for its electrical systems and steam turbines. It had the use of the patents of GE of the U.S.A. and access to that company's experience, modifying the designs to suit the British and Colonial markets.

The British Thomson-Houston Co Ltd (BTH) of Crown House, Aldwych, London, WC2. Works at Rugby. Birmingham Office at 10 and 11 Snow Hill. Also of Alma Street, Coventry.

Offices and Depots: Belfast, Birmingham, Blackburn, Blackpool, Bournemouth, Bradford, Bristol, Cambridge, Cardiff, Cheltenham, Chester, Colchester, Dublin, Dundee, Edinburgh, Glasgow, Guildford, Hastings, Hull, Leeds, Leicester, Liverpool, Manchester, Middlesbrough, Newcastle-on-Tyne, Norwich, Nottingham, Oxford, Plymouth, Portsmouth, Sheffield, Southampton, Stoke-on-Trent, Swansea. (1937)

See also -

1886: The Laing, Wharton and Down Company was formed to sell products from the Thomson-Houston Co (previously American Electric Company). They soon won a contract for electrical lighting for the east end of London.

1889 Incorporated as a limited company: the Laing, Wharton and Down Construction Syndicate.

1892: General Electric Co (USA) was created by the merger of Thomson-Houston and Edison General Electric.

1894: Laing, Wharton and Down Construction Syndicate was renamed British Thomson-Houston after acquiring the British rights to Thomson-Houston patents[2]. BTH was majority owned by General Electric Co of USA. Started to set up factories in the British Midlands. Competed for electrical generation and distribution contracts with British Westinghouse, mirroring the battles in the U.S.A. between their parents, General Electric and Westinghouse.

1896 The company was voluntarily wound up and replaced by another company of similar name[3]

1899 BTH chose Rugby, Warwickshire, as site for new factory, due to its good accessibility by rail and a local coal supply.

1900 BTH bought Glebe Farm (on the west side of Mill Road north of the railway) for £10,000, from Thomas Hunter and Co, on which to build the factory. The Power Act of 1900 was passed. It allowed BTH and British Westinghouse to win new contracts to supply electric power to large areas of the country.

1900 June. Tramways and Light Railways Exhibition at Islington. Showed two tramcars made by Hurst, Nelson and Co and equipped by them[4]

1902 In March BTH opened a new factory in Mill Road, making electric motors and generators. The company also obtained a licence to produce the Curtis steam turbine, which became one of their major products.

1903 Won contract from North Eastern Railway for supply of electrical equipment for motor units, carriages and laying of third rail. British Westinghouse received a contract for switchboards, transformers and sub-stations [5].

1903 Sprague-Thomson-Houston system of multiple unit train control accepted for District Company's electrification in London [6].

1904 Contractors for the Central London and Great Northern and City lines electrification using direct current (dc) electricity [7].

1904 BTH started making turbines, designed by Frederick Samuelson.

1904 Produced an experimental petrol-electric vehicle, using an engine and chassis made by a Coventry firm.[8]

1905 BTH made its first turbo-alternator, a 700kW vertical machine for Harrogate Corporation.

1905 BTH were the first to apply electric power to drive a textile mill in the UK (at the Acme cotton mill, Pendlebury, owned by the Linen Thread Co). This saved 3000 tons in the weight of the mill's machinery and structure, which was important as one corner of the mill was supported over an old mine shaft. The yarn from this mill was sold at a premium because the electric drive resulted in a more even twist and texture. The leading figure in the introduction of the electric drive was John Shaw of BTH[9]

1907 BTH started a joint venture with Wolseley to make petrol-electric buses, but they were too heavy and expensive to buy to be competitive.

1908 BTH displayed a 3-phase alternator driven by a Curtis turbine, a motor drive system for textile machinery and a tungsten filament lamp at the Manchester Electrical Exhibition[10]. F. Samuelson had abandoned vertical turbines in favour of horizontal, and this 1000kW 3000 rpm machine was the first from BTH. GE in New York had resisted this change, but later admitted that Samuelson was correct. The alternator, designed by Frederic Horton Clough, was influential in the industry, having a distributed rotor winding carried in radial slots.[11]

1909 Supplied generation plant in London to power a new electric trolley system.

1911: Acquired licences for all of General Electric's drawn-wire light bulbs, which they produced under the Mazda trademark[12].

1914 Listed as electrical engineers and manufacturers of apparatus and supplies for electric traction, lighting and power. Specialities: "Curtis" turbines, horizontal and vertical type, "Mazda" metallic filament drawn wire lamp, railway and tramway equipments. Employees 5,600. [13]

WW1: BTH expanded into naval electrical equipment, supplying the Royal Navy with various lighting, radio and signalling gear. Using its experience in making filament lamps, became a manufacturer of radio valves[14]

1916 Howard C. Levis became chairman of BTH.

1917 Advert. Electrical engineers and manufacturers with works at Rugby, Coventry and London. [15]

1918 and after: BTH expanded dramatically, adding or expanding factories at Willesden, Birmingham, Chesterfield, and Lutterworth. (It later had factories in Coventry, and in Larne in Northern Ireland.)

1920 Board of Trade report into "Electric Lamp Combine" recognised the Electrical Lamp Manufacturers Association was set up principally in the interests of BTH, GEC and Siemens Brothers and Co[16].

1920 April. Portable Wireless Two-Valve Receiver. Details in The Engineer[17]

1922 One of the six telecommunications companies that founded the British Broadcasting Company.

1922 Exhibited a crystal set at the 1922 Wireless Exhibition as well as valve receivers.

1923 Mr W. C. Lusk became managing director and Mr H. C. Levis who held the position of chairman and managing direcotr to the company continued as chairman of the company. [18]

1924: BTH's Building 52, the research laboratory, was purpose built.

1925 February 19th. Founding shareholder in Austin Electric Co

1926: Gerard Swope, president of the U.S. General Electric, proposed that BTH, Westinghouse, GEC and the English Electric Co should amalgamate. Hugo Hirst of GEC was not interested in Swope’s scheme.

1926 Started producing large welded fabrications for machinery.

1927 See Aberconway for information on the company and its history.

1927 - April. BTH obtained a twelve months' contract from the City and County Borough of Belfast for the supply of Mazda electric lamps.[19]

1927 BTH was one of the UK's major electrical-machinery and plant manufacturers with 12,000 employees; others major manufacturers beings GEC, Metropolitan-Vickers (which incorporated British Westinghouse), English Electric Co, and C. A. Parsons and Co[20]. Works at Rugby (turbo plant, heavy machinery, electric traction equipments and lighting and radio material), at Birmingham (electric motors), at Coventry (radio apparatus and fractional horse-power motors), and at Willesden (switch gear)[21].

1928 Alexander Dow of the Detroit Edison Co visited Rugby and placed an order for a 10MW turbine to operate at the then-unprecedented temperature of 1000degF. The inlet pressure was 365 psig. It operated satisfactorily for 26,500 hours, after which it was reconstructed by BTH as a superimposed turbine for the Detroit Edison Co's Delray Station, operating at 815 psig, 900F.

1928 General Electric Co (USA) owned nearly all of the Ordinary shares of the company[22].

1928 BTH was acquired by Metropolitan-Vickers, a company of similar size and product lineup, which had been bought from Vickers by General Electric Co (USA) before passing control to F. Dudley Docker. Combined they would be one of the few companies able to compete with the Marconi's Wireless Telegraph Co or the English Electric Co on an equal footing. The new group was called Associated Electrical Industries (AEI)[23]. Also included in the new group were Edison Swan Electric Co (Ediswan) and Ferguson Pailin of Openshaw, Manchester (which BTH had been in the process of buying). As part of the merger, all of the Ordinary shares in BTH held by GE of USA were acquired[24]. The hopes for the future of the new group were handicapped by poor communication and intense rivalry between the two power equipment companies, as well as increasing over-capacity in the industry; the two companies maintained their separate quotations and their own identities until 1960. Rivalry between them continued such that AEI was never able to exert effective control over its two competing subsidiaries. Howard C. Levis became chairman of AEI.

1928 BTH, which had been making the "Mazda" valves, ceased valve making except for special purpose valves that it required for its production of non-domestic electronic equipment; the AEI group's valve production was taken on by Edison Swan Electric Co. BTH undertook radio set manufacturer for the group; production of domestic receivers ended after about 3 years[25]

c.1929 Started to supply control systems, traction motors and lineside equipment to the Southern Railway.

c.1930 AEI started to build west of the footpath that runs north through the AEI site in Rugby to the Leicester Road.

1930 First mercury arc rectifier in the UK for heavy railway service, installed by BTH at Hendon for the London Electric Railway Co.

1930 Turbine and generator made by BTH Rugby for the Detroit Edison Company's Delray Power House No. 3, to run with steam at the then high steam temperature of 1,000 degF. [26]

1932 Orders received for six turbine-driven gas boosters for Beckton Gas Works, and two for the Woodall Duckham Vertical Retort and Oven Construction Co for Pretoria. [27]

1933 The Rugby foundry was reorganised to increase production of small castings and transfer large casting production to the Metropolitan-Vickers foundry at Trafford Park. The land and premises of the former Ladywood Iron Works at Lutterworth were also purchased.

1933 BTH developed and supplied equipment for reproducing sound in cinemas offering greater fidelity than previously available[28].

1934 BTH-made domestic appliances, except refrigerators, were marketed through Hotpoint Electric Appliance Co, a subsidiary of BTH[29].

1936 Frank Whittle's Power Jets company started work on building the world's first prototype jet engine at the BTH works in Rugby. BTH had a major role in developing it. Development was later moved to the Lutterworth works, which were falling into disuse at the time. BTH's directors seemed sceptical of the design and offered little help.

1937 Manufacturers of magnetos, starters and air compressors. "B.T.H." Electrical Equipment. [30]

1938 An end-of-year newspaper review indicates the breadth of work undertaken by the company: steam turbine generators for public and industrial power supplies; turbo-compressors for mines; rotary converters; turbine-driven gas blowers and exhausters; turbine-generators for ships in cluding the 'Queen Elizabeth' and the new 'Mauretania'; switchgear; transformers; trolley bus electrical equipment; railway traction equipment; large rectifiers; electric motors, including large motors for rolling mill drives; mine winders and haulage equipment for UK, South Africa, China, India; street lighting; TV and recording equipment; electrical insulating material.[31]

1939 See Aircraft Industry Suppliers

1940 Fabroil silent pinions and a range of electrical equipment. [32]

WW2 BTH expanded north of the River Avon into the Boughton Road site to make magnetos for aircraft engines and other war products.

1940: BTH decided they were not really interested in making jet engines due to their commitment to electrical equipment. Rover was soon selected to make jet engines.

1943 Rover passed on jet engine making to Rolls-Royce.

1944 The Lutterworth Power Jets work was nationalized.

1945 Post-WWII. Oliver Lyttelton took over AEI, and started a massive expansion.

1947 The Hungarian scientist Dennis Gabor invented holography at the BTH site in Rugby.

1953 AEI acquired Siemens Brothers.

1956 Ediswan trademark appeared on semiconductors.

c.1956 AEI amalgamated Siemens and Edison Swan Electric Co as Siemens Edison Swan[33]

1957 AEI started to introduce product-based businesses: AEI Lamp and Lighting Co, as well as Birlec and Hill Top Foundry Co., were associated with the BTH business[34]

1957 The massive new £8 million turbine works was opened at Larne.

1957 or after: BTH won the contract to build the new Buenos Aires power station, valued at £35 million. Rivalries intensified with Metrovick. Lyttelton continued to try to reduce this friction, leading to several unsuccessful reorganizations and slipping profits.

1960 Jan 1: To try to cure the internal revalries, AEI stopped using the names BTH and Metrovick. This led to a huge falling-off in sales because no-one had heard of AEI before, and in turn, a massive drop in AEI's stock price. Continued attempts to streamline what was two separate management structures continued to fail, and by the mid-60's the entire AEI empire was in financial trouble.

1960 Advert. Generators, motors, rheostat and electronic control gear, switchgear, transformers, rectifiers, helical gearing etc. [35]

1962 Commissioning of Britain's first commercial nuclear power facility at Berkeley.

1963-1967 Construction and commissioning of the £25M radar dish at Chilbolton Observatory.

1967 AEI brands included Metropolitan-Vickers, BTH, Edison Swan and Ediswan, Siemens Brothers, Hotpoint, Birlec and W. T. Henley.

1967 GEC bought AEI outright. GEC thus became the UK's largest electrical group.

1969 Marconi Radar Systems Ltd (MSRL) was formed from GEC-AEI Electronics (Blackbird Road and New Parks, Leicester), Marconi's Radar Division (Chelmsford) and Elliott's Aerospace Control Division.

1980s GEC Rugby shrank. Many buildings were pulled down. The area west of the Black Path became a supermarket site. The Boughton Road site became several separate small firms.

1989 GEC Rugby was split into GEC Alsthom and Cegelec Projects.

1998 GEC Alsthom and Cegelec Projects were reunited as Alstom.

2007 The firm's clubhouse on Hillmorton Road was pulled down, and its surrounding sports field was used for house building along its south edge.

See Also


Sources of Information

  1. Oxford Junior Encyclopaedia. Volume VIII. Engineering. Oxford University Press, 1955
  2. The Times, 17 August 1894
  3. The London Gazette 22 May 1896
  4. The Engineer of 29th June 1900 p667
  5. The Times, 31 January 1903
  6. The Times, 22 September 1903
  7. The Times, 14 March 1904
  8. 'B.T.H. Reminiscences - Sixty Years of Progress' compiled by H. A. Price-Hughes, BTH, 1946, p.22
  9. 'B.T.H. Reminiscences - Sixty Years of Progress' compiled by H. A. Price-Hughes, BTH, 1946, pp.27-8
  10. The Times, 7 October 1908
  11. 'B.T.H. Reminiscences - Sixty Years of Progress' compiled by H. A. Price-Hughes, BTH, 1946, p.21
  12. The Engineer of 25th August 1911 p197
  13. 1914 Whitakers Red Book
  14. [1] Competition Commission
  15. Mechanical World Year Book 1917. Published by Emmott and Co of Manchester. Advert p149
  16. The Times, 17 March 1920
  17. The Engineer of 16th April 1920 p394
  18. The Engineer 1923/01/19
  19. The Engineer 1927/04/15
  20. A History of the County of Warwick: Volume 7: The City of Birmingham (1964)
  21. The Basic Industries of Great Britain by Aberconway: Chapter XXII
  22. The Times, 20 February 1928
  23. The Times, 6 December 1928
  24. The Times, 9 May 1929
  25. Competition Commission report
  26. Engineering 1934/01/05
  27. Rugby Advertiser - Friday 15 January 1932
  28. The Times, 24 October 1933
  29. The Times, 12 April 1934
  30. 1937 The Aeroplane Directory of the Aviation and Allied Industries
  31. Rugby Advertiser - Friday 16 December 1938
  32. Mechanical World Year Book 1940. Published by Emmott and Co of Manchester. Advert p31 & p33
  33. The Times, Jun 12, 1958
  34. The Times April 10, 1958
  35. Mechanical World Year Book 1960. Published by Emmott and Co of Manchester. Advert p143
  • [2] Wikipedia
  • 'B.T.H. Reminiscences - Sixty Years of Progress' compiled by H. A. Price-Hughes, BTH, 1946
  • Stationary Steam Engines of Great Britain by George Watkins. Vol 10