The IET Archives has just completed the cataloguing of a collection called the ‘John T Irwin papers’. Irwin, shown in the image above, was a prolific inventor of electrical instruments and had several careers. Firstly as an instructor and lecturer at the Central Technical College, later the City and Guilds (Engineering) College, then as a farmer and hydro-electric engineer working for the Electricity Board of Northern Ireland (these last two roles of farmer and engineer undertaken at the same time). Amongst the surprises in the collection there is a letter from a Nobel Prize winner and another letter from one of the key engineers behind ‘talking pictures’!

John T Irwin, AMIEE (1879-1968)

John T Irwin was born in County Londonderry, Northern Ireland to a farming family. He was educated first at Mulderg School and then Mr Tate’s school in Limavady where, in addition to normal schooling, farming methods were taught. After leaving the Limavady School, in 1883 he went to Londonderry Academy (which became Foyle College in 1896).

In September 1898, at the age of 19, he became a student at Faraday House, the Electrical Standardizing, Testing and Training Institution, London, which had been established in 1890. He completed the Junior and Senior terms by July 1899, and during the second year worked at the affiliated firm of S Z de Ferranti, Hollinwood, Lancashire, manufacturer of steam engines and electrical alternators. At his final examinations he was head scholar and prizeman of the year, being first in nearly every subject. In 1900 he won a prize of £5 which he used to visit the Paris Exhibition. Irwin’s Faraday House certificate from November 1900 is shown below.


After his time at Faraday House, Irwin went to Willans and Robinson Ltd, Rugby, to be in charge of its boiler works and its power station. He also lectured in electricity and magnetism at Rugby Technical College.

Early in 1904, Irwin moved to London to become assistant instructor in machine design at the Central Technical College, Exhibition Road, South Kensington, which later became the City and Guilds (Engineering) College, part of Imperial College. In 1905 he became lecturer in machine design and on electrical instruments under Professor Ayrton. During his time at the college he designed several inventions, including his hot-wire oscillograph (an example is in the Science Museum) and improvements in ‘selective electrical signalling’ to enable a number of messages to be transmitted through the same medium without appreciable interference. In 1908 he received an IEE prize for his paper on ‘the magnetic leakages in induction motors’ and he continued to publish papers while at the college. One of Irwin’s inventions was exhibited at the 1911 International Industrial Exposition in Turin and his Diploma of Honour for exhibiting is shown below;


During World War I, Irwin was seconded for wartime research. He was initially in Kent where he developed a giant parabolic reflector at Dover used as an early aircraft detection device. Later he was at the Admiralty research establishment at Parkeston Quay, working on submarine detection.

When released from the Admiralty at the end of the war, Irwin decided to return to Northern Ireland. This was partly for family reasons, out of a sense of duty to take over the family farm at Bovally, Limavady, but he also thought there would be an opportunity to get established as a consulting hydro-electric engineer which he saw as the best future source of energy for the province. Over the next 20 years he was responsible for many hydroelectric schemes throughout the North of Ireland, starting with installing electricity in his own farms. Irwin was part-time manager of the Limavady Electric Supply Company and worked for the Electricity Board for Northern Ireland as its Chief Hydro-electricity Engineer.

In the 1950s Irwin was involved in various hydro-electricity schemes including generation projects on the Lower Bann and the River Mourne. These major projects were stopped as it was anticipated that the Electricity Board would be constructing an atomic power station for future generations. The collection includes correspondence and documents from the hydro-electricity schemes with which Irwin was involved including the Lower Bann and River Mourne projects. Two images, from the appendix of plans and sections for the Lower Bann project, follow.



Irwin continued farming at Bovally until his death in 1968 at the age of 89. The water turbine continued to supply the farm with electricity until a mains supply was installed in the mid-1960s.

Correspondence with a Nobel Prize winner and a key engineer behind ‘talking pictures’

After moving to Northern Ireland after WW1, Irwin continuing his instrumentation design work that he had started while at Imperial College. The experimentation work was carried out by the Cambridge Instrumentation Company in London, and the exchange of calculations and ideas was carried out by letter. Much of this correspondence, which appears to have ceased in the late 1920s, can be found in the collection along with his patent submissions for the period 1907 to 1925.

Amongst this patent and design work correspondence is a lengthy and friendly letter to Irwin from Stanley Watkins (1888-1975) dated 27 January 1921. Watkins, the Western Electric electrical engineer, was one of two British engineers, together with George Groves, who played a major role in the development of ‘talking pictures’ when working for Western Electric and Warner Brothers in America. Watkins and Groves had a British Film Institute plaque unveiled in their memory at the Warners Cinema, Leicester Square, in 1996 upon the commemoration of the centenary of cinema.


The contents of this 6-page letter (last page shown above), speak of instrumentation and instrument patents and the likelihood of Western Electric taking up Irwin’s patent. Watkins also compares Irwin to Charles Darwin in his ability to produce great work and makes the following disparaging remark about GEC instrumentation;

“Heaven help you if you ever get the GEC to build instruments for you. Have you ever used, or ever seen, one of their oscillographs. It isn’t design – it’s malpractice!”

John T Irwin wrote a book in 1925 about oscillographs which is still available via the IET Library! It is this book that is probably being referred to in a 1-page letter in the collection written by Willem Einthoven, dated November 1925. Einthoven was the winner of the Nobel Prize in Medicine in 1924 for inventing the first practical system of electrocardiography. Einthoven thanks Irwin for his ‘valuable little book’ in the letter which is reproduced below.


The John T Irwin collection has been catalogued with an archive reference SC MSS 281 and is available to consult by appointment at the IET Archive Centre, Savoy Hill House, London.