Dictionary of National Biography, 1912 supplement/Ayrton, William Edward

AYRTON, WILLIAM EDWARD (1847–1908), electrical engineer and physicist, born in London on 14 Sept. 1847, was son of an able barrister, Edward Nugent Ayrton (1815–1873), and nephew of Acton Smee Ayrton [q. v.] [see for earlier relatives Edmund Ayrton and William Ayrton]. Ayrton's father, a distinguished linguist, had severe ideas of education, and tried, without much success, to enforce on his son the practice of speaking different languages (including Hebrew) on each day of the week. After attending University College school from 1859 to 1864, he entered University College London in 1864-5, and in July 1865 and July 1866 took the Andrews mathematical scholarships for first and second year students respectively.

In 1867 he passed the first B.A. examination of the University of London, with second-class honours in mathematics, and entered the Indian telegraph service, being sent by government on passing the entrance examination to Glasgow to study electricity under (Sir) William Thomson, afterwards Lord Kelvin [q. v. Suppl. II]. Of his work in Kelvin's laboratory he gave a vivid account in 'The Times,' 8 Jan. 1908. After some practical study at the works of the Telegraph Construction and Maintenance Company he went out to Bombay in 1868, his appointment as assistant-superintendent of the fourth grade dating from 1 Sept. 1868. With Mr. C. L. Schwendler, electrician on special duty, he soon worked out methods of detecting faults which revolutionised the Indian overland system of telegraphs. In 1871 Ayrton was moved to Alipur ; returning on short leave, he married in London, on 21 Dec. 1871, his cousin, Matilda Chaplin [see Ayrton, Matilda Chaplin]. In 1872-3 he again returned to England for special investigations ; and was also placed in charge of the testing for the Great Western Railway telegraph factory under (Sir) William Thomson and Fleeming Jenkin [q. v.]. In 1873 the Japanese government founded the Imperial Engineering College at Tokio, which became for a time the largest technical university in the world. Ayrton accepted the chair of physics and telegraphy, and proceeding to Japan created a laboratory for teaching applied electricity. The first of its kind, this laboratory served as a model for those which Ayrton himself organised in England later, and through them for numerous other laboratories elsewhere. During the five years in Japan Ayrton with his colleague, Professor John Perry, carried out an extraordinarily large amount of experimental work ; their joint researches include the first determinations of the dielectric constant of gases and an important memoir on the significance of this constant in the definition of the electrostatic unit of quantity ; memoirs on the viscosity of dielectrics, the theory of terrestrial magnetism, on electrolytic polarisation, contact electricity, telegraphic tests, the thermal conductivity of stone, a remarkably ingenious solution of the mystery of Japanese * magic ' mirrors, and a paper interesting to the philosophy of aesthetics on 'The Music of Colour and Visible Motion.' In 1878 Ayrton returned, home and acted as scientific adviser to Messrs. (Josiah) Latimer Clark [q. v.] and Muirhead. In 1879 Ayrton became a professor of the City and Guilds of London Institute for the Advancement of Technical Education, an institution founded by certain City companies. He delivered the inaugural address on 1 Nov., and began the institute's work in the basement of the Middle Class Schools, Cowper Street. He and Professor Henry Edward Armstrong, F.R.S., the chemist, were at first the sole professors, and his first class consisted of an old man and a boy of fourteen. Perry soon joined the small staff and the movement spread rapidly. In 1881 the governors of the institute laid the foundation of two colleges, the Finsbury Technical College and the Central Technical (now the City and Guilds) College, South Kensington. Ayrton acted as professor of applied physics at Finsbury from 1881 till 1884, and then became first professor of physics and electrical engineering in the Central Technical College, a post which he held till his death.

Ayrton and Perry continued till about 1891 their scientific partnership ; in 1881 they invented the surface-contact system for electric railways with its truly absolute block system, which in 1882 they applied together with Fleeming Jenkin to 'telpherage,' a system of overhead transport used little in England, but to a greater extent in America.

In 1882 Ayrton and Perry brought out the first electric tricycle ; they next invented in rapid succession a whole series of portable electrical measuring instruments, an ammeter (so named by the inventors), an electric power meter, various forms of voltmeter, and an instrument for measuring self and mutual induction. Great use is made in these instruments of an ingeniously devised flat spiral spring which yields a relatively great rotation for a small axial elongation. The instruments have served as prototypes for the measuring instruments which have come into use in all countries, as electric power has become generally employed for domestic and commercial purposes. Ayrton and Perry also invented a clock meter and motor meter which served as models for the meters now used, and would have brought them an immense fortune, had they not abandoned their patents at too early a date. Of the instruments other than electric invented by them about this time may be mentioned transmission and absorption dynamometers, and a dispersion photometer. Apart from specific inventions of apparatus and instruments the two men carried out investigations into almost every branch of electric engineering and the branches of mechanical engineering specially useful to the electrical engineer.

In 1891 Ayrton and Perry published their last joint paper, in which, together with one of Ayrton's pupils, Dr. W. E. Sumpner, they showed that the theoretical law previously worked out for quadrant electrometers was not valid. From 1891 onwards Ayrton worked mainly in collaboration with Mr. Thomas Mather, F.R.S. (first his assistant and later his successor), with Dr. Sumpner, and with others of his pupils, past and present. Among his later researches of importance are those on accumulators, on Clark cells, on galvanometer construction, on glow lamps, on non-inductive resistances, on the three voltmeter method of determining the power supplied to a circuit (devised jointly with Dr. Sumpner), on the very ingenious 'universal shunt box' and electrostatic voltmeters, invented jointly with Mr. Mather, work on alternate-current dynamos, on ampere-balances and on transformers, an elaborate determination of the ohm in conjunction with Principal John Viriamu Jones [q. v. Suppl. II], and an investigation of the phenomena of smell, dealt with in Ayrton's presidential address to the mathematical and physical section of the British Association in 1898. An address on 'Electricity as a Motive Power' delivered to working men at the Sheffield meeting of the British Association, 23 Aug. 1879, put forward for the first time the important suggestion that power could be distributed at once most economically and safely by means of high tension currents of relatively small quantity 'transformed down' at the distant end of the transmission system. In the lecture delivered at the Johannesburg meeting of the British Association on 29 Aug. 1905, Ayrton pointed to the fulfilment of his prophecies ; and at the same time discouraged the project for utilising the Victoria Falls on the Zambesi as a generating station, on the ground that the plan proposed was inefficient and that their beauty would be spoilt to no purpose.

Research work was only one side of Ayrton's many activities ; he was employed as a consulting electrical engineer by government departments and by many private firms, and took part as an expert in many important patent cases. He invariably declined to act in legal cases unless a preliminary investigation had convinced him of the soundness of the cause for which he was to appear.

Ayrton was elected fellow of the Royal Society in 1881, and was awarded a royal medal in 1901. In the Institution of Electrical Engineers (founded in 1871 as the Society of Telegraph Engineers and Electricians) Ayrton took a special interest, and the development of the institution, which he joined in 1872, was largely due to his energetic support. From 1878 to 1885 he acted as chairman of the editorial committee and as honorary editor of the 'Journal.' In 1892 he was elected president and from 1897 to 1902 acted as honorary treasurer of the institution. He was president of the Physical Society from 1890 to 1892.

For the admiralty Ayrton carried out important investigations on the heating of cables used in the wiring of warships, on searchlights (in conjunction with his second wife), on sparking pressures, and other matters, and he was a member of the committee appointed in 1901 to consider and report upon 'the electrical equipment of His Majesty's ships.' He served on the committee appointed in 1889 to advise the board of trade on electrical standards, of which the report led to the formation of the present board of trade testing laboratory; and he also served on the general board of the national physical laboratory and on juries of several international exhibitions, including that of Chicago in 1893 and of Paris in 1900. He acted in 1903 as a member of the educational commission organised by Mr. Alfred Mosely, C.M.G., to visit the United States and report on American education.

Above all Ayrton threw himself heart and soul into his teaching. The laboratories, which he created at Finsbury and South Kensington, turned out hundreds of electrical engineers, and by his stirring addresses on technical education, he played an important part in the technical development of the country. His public lectures were elaborately prepared, abounded in striking illustration, and were delivered with the skill and fire of an accomplished advocate. In the laboratory he taught each student to carry out every experiment 'as if he were the first who had ever investigated the matter,' and criticised the work that came to his notice in the most minute detail, and on any indication of want of energy or thoroughness he was mercilessly severe. He treated himself with the same severity; for years together he took no rest from work, and towards 1901 he developed weakness of the arterial system, from which he ultimately died on 8 Nov. 1908, at his house, 41 Norfolk Square, Hyde Park. He was buried at the Brompton cemetery without religious rites, but with a choral service of sacred music. His son-in-law, Mr. Israel Zangwill, and Professor Perry delivered addresses over the grave.

By his first marriage Ayrton had one daughter, Edith Chaplin Ayrton, who married the writer, Israel Zangwill, and is herself the author of several novels. On 6 May 1885 he married Miss Sarah (Hertha) Marks, a distinguished Girton student, who was in 1906 awarded the Hughes medal of the Royal Society for her researches on the electric arc and on sand ripples; by his second marriage he had one daughter, Barbara Bodichon, now married to Mr. Gerald Gould.

The list of Ayrton's papers, 151 in all, includes eleven published before 1876, independently; seventy published between 1876 and 1891 with Prof. Perry (of which two were in collaboration with other workers); and twelve in collaboration with Professor Mather. Ayrton published in 1887 a work on 'Practical Electricity,' which went through eleven editions in his lifetime and has since been reissued as a joint work with Professor Mather.

It is as a pioneer in electrical engineering and a great teacher and organiser of technical education that Ayrton will be remembered. He was a man of restless energy and of the most varied capacities, scientific, dramatic, and musical, and alive to problems of philosophy and religion to which he refrained from devoting his time only because he saw no possibility of immediate solutions. Like other members of his family he was an active and generous supporter of women's rights.

Ayrton was somewhat above the medium height, fair, with brown hair and blue eyes. A medallion in plaster by Miss Margaret Giles (Mrs. Bernard Jenkin) is in the possession of Mrs. Ayrton.

[A short account of the Families of Chaplin and Skinner and connected Families, privately printed, 1902, for Nugent Chaplin; Univ. Coll. School Register for 1831-1891; Univ. Coll. London, Calendars for 1865-6, pp. 55, 118; ib. for 1866-7, pp. 67, 116; ib. for 1867-8, pp. 109, 130; University of London Calendar; Government of India Telegraph Department, Classified Lists . . . and Distribution Returns for years ending 31 March 1869 (pp. 3, 50) and 1870-1873; article by P. J. Hartog in Cassier's Magazine, xxii. 541 (1902); obituary notice in The Central (Journal of the City and Guilds of London Central Technical College), vol. vii. (1910) (with portrait from photograph) by Maurice Solomon and Professor Thomas Mather, F.R.S., with a bibliography containing a 'fairly complete' list of papers, by F. E. Meade, as well as in Nature, 19 Nov. 1908, and in Proc. Roy. Soc. 85 A, p.i., by Professor John Perry; information from Mrs. Ayrton and personal knowledge.]

P. J. H.