Hertha Marks Ayrton
Marjorie Malley


Hertha Ayrton, née Phoebe Sarah Marks, was born on April 28, 1854, in Portsea, England, the third of eight children of Levi and Alice Theresa (Moss) Marks. Levi Marks, an impecunious clockmaker and jeweler, had fled his native Poland as a young man to escape anti-Semitic persecution. He died in 1861, leaving the family in debt. Alice Marks struggled to support her large family through income from needlework and managed to be active in civic and philanthropic ventures as well. She was said to have always been "at everybody's beck and call . . . land] never known to refuse an appeal for help'' (Sharp 1926, 5).

At the age of nine, Marks went to London to live with her maternal aunt, Marion Harzog. Marion and Alphonse Harzog owned a school, where they educated her with their own children. The Cambridge-educated Numa Harzog taught mathematics to his cousin Sarah, and Marcus Harzog influenced her philosophical views and introduced her to some of the local intelligentsia. Young Marks's many friends and acquaintances included George Eliot.

While she was in her teens Sarah Marks adopted the name Hertha, after the Teutonic earth goddess as eulogized by Swinburne in a popular poem that attacked conventional religious views. This transformation coincided with Marks's departure from the Jewish religion, which greatly disappointed her devout mother. Marks considered herself an agnostic for the rest of her life, but she always remained proud of her Jewish heritage.

She supported herself by tutoring and embroidery work, sending much of her earnings to her impoverished family. Her dream of a university education was made financially possible largely through the efforts of Mme. Barbara LeighSmith Bodichon, one of the founders of Girton College. Mme. Bodichon, a gifted and unconventional woman who had studied under the artist Camille Corot, was passionately interested in promoting higher education for women. Marks entered Girton in 1876 after having passed the Cambridge University Examination for Women in 1874 with honors in English and mathematics. Her progress was impeded by repeated bouts of illness of uncertain origin and marred by disappointing performances on examinations, which were a source of great stress for her. She was coached by Richard T. Glazebrook and completed the Cambridge Tripos in 1881. At that time women were not eligible for the university degree.

For several years Marks supported herself by teaching. In 1884 she patented a line divider, an instrument for dividing a line into any number of equal parts. It was of potential use for artists, architects, engineers, and surveyors. She had always been interested in mechanical devices (perhaps reflecting her father's influence) and showed ability in mathematics. After this success, achieved with partial financial backing from Mme. Bodichon, she began to consider seriously a scientific career. The popular and technically promising field of electricity caught her interest, and Mme. Bodichon again came to the rescue with funds. Marks began studies at the Technical College, Finsbury, in 1884 under the professor of physics and noted electrical engineer William Edward Ayrton.

A widower with a young daughter, Ayrton was very supportive of women's education and legal rights. The relationship between the professor and his student deepened, and they were married on May 6, 1885.

Marks's marriage relieved her of the continual pressure of monetary worries. She pursued her chosen field for several years, lecturing to women on practical] electricity in 1888. However, the combination of poor health, the added domestic and social responsibilities of her marriage, and the birth of their daughter Barbara (named after Mme. Bodichon), left Ayrton little time for professional work during the next few years . The death of Mme . Bodichon in 1891 deeply grieved Ayrton . But Mme. Bodichon was a benefactor in death as well as in life, leaving Ayrton a sum that enabled her to support her aging mother and to hire a housekeeper.

Ayrton resumed her work in 1893. First she took charge of some of Professor Ayrton's ongoing experiments on the electric arc while he traveled to an electrical congress. Soon she became involved in her own investigations of the arc. A lengthy series of papers followed, which Ayrton incorporated into a comprehensive book on the arc published in 1902.

The IEE awarded Hertha Ayrton a prize of £10 in 1899 for her paper on the hissing arc and took the unusual step of permitting a woman to read her own paper. In the same year the IEE elected Ayrton their first woman member.

With her professional reputation now established, doors began to open for Ayrton . In 1899 she read a paper at the British Association meeting. demonstrated the electric arc at the Royal Society's evening Conversazione, and presided over the science section of the International Congress of Women. The following year she read a paper on the arc at the International Electrical Congress in Paris.

Ayrton was soon spending increasing amounts of time caring for her husband, whose health was failing rapidly. She turned necessity to her advantage by analyzing sand ripple patterns while he rested at the seashore in 1901. These studies led to further work on hydrodynamics. She also performed a major portion of the investigations of searchlight carbons commissioned from her husband by the British Admiralty. William Ayrton died in 1908. In 1906 the Royal Society awarded Ayrton the Hughes Medal for her experimental investigations of the electric arc and also for her work on sand ripples. In spite of this and other honors‹she apparently was the first woman to read her own paper to the Royal Society, in 190~~the society refused to elect her a fellow, deciding that as a married woman she was not qualified for election.

Ayrton was vivacious, attractive, independent and outspoken, yet proper and considerate of others. Though diminutive in stature, she made a strong impression on people. Even a detractor attested to her ' considerable personal charm" (Armstrong 1923), a quality that contributed to her successes. She had many friends from whom she received much support and encouragement.

One friend for whom she felt a special kinship was Marie Curie.* who also struggled to juggle family and career in a society that was not prepared to support such an extraordinary combination. Both women were repeatedly accused of riding on their husband's scientific coattails. ''An error that ascribes to a man what was actually the work of a woman has more lives than a cat," wrote Ayrton in Marie Curie's defense (Sharp 1926, 117), but doubtlessly with her own experiences in mind. During 1912 Ayrton provided a refuge for Curie and her daughters, enabling the famous physicist to recuperate anonymously from stress and illness.

Ayrton's personal and social values were profoundly affected by her direct experiences with poverty and discrimination. her identification with her Jewish heritage, and her mother's example of generosity and self-sufficiency. She was active in charitable causes as well as in the suffrage movement. She claimed that reading the story of Vashti in the Book of Esther as a child had made a suffragette of her. Ayrton took part in the demonstrations of 1910, enduring the physical and verbal abuse wrought upon the demonstrators as well as the disapproval of her more conservative acquaintances. She also nursed the movement's hunger strikers back to health under the shadow of constant police and press surveillance.

In 1915 Ayrton invented a fan to dispel and clear poisonous gases from the trenches at the front. The hand-operated device worked by creating air vortices similar to the water vortices she had investigated earlier. Ayrton promoted it with the zeal of a crusader. Unfortunately, the inexpensive wooden and canvas fan appeared almost ludicrously simple. It required a specific beating technique and was effective only in winds less than nine miles per hour (although in 1917 Ayrton developed a mechanically driven fan to use in high winds). Indifference coupled with bureaucratic errors and delays prevented the Ayrton fan from being widely used. a frustration that drained her emotionally and pained her deeply.

After the war Ayrton worked on modifications of the fan for municipal and industrial purposes. as well as the theory of vortices. She joined the Labour Party and became involved with the newly founded International Federation of University Women and the National Union of Scientific Workers, both of which appealed to her internationalistic and democratic sentiments. Ayrton died of septicemia at Sussex on August 26. 1923. She left the considerable sum of £8,160 to the IEE, the organization that had welcomed her without prejudice and helped launch her career.


Ayrton made significant contributions to the technology of the electric arc. The direct current arc was of substantial commercial and industrial importance when she began her research in 1893. since it was widely used for lighting. The main technical problem was to ''secure the maximum production of light from a given expenditure of power in the generator' ' ( Ayrton, The Electric Are 1902. vii). Arc lamps were plagued with problems. They hissed, sputtered. hummed. and rotated. producing unsteady illumination in a changing array of colors. Their heat melted most materials, a challenge tor those who wished to devise suitable insulators. Since the arc electrodes were consumed during operation, the arc length continually changed, which required adjustments to be made in the circuit and in the mirror's position in searchlights.

She contributed to a better understanding of this subject by determining the relations among power supplied, potential across the arc, current, and arc length. She found that the potential required to send a given current through an arc of fixed length depended primarily on the nature of the surface of the depression (crater) that forms on the tip of the positive carbon during operation. Her tour /e force was her analysis of the hissing arc, whose instability presented a baffling engineering problem. She found that this undesirable condition resulted from oxidation of the positive carbon. (In the stable arc only vaporization of the carbon occurred.) Ayrton showed that current practices in the manufacture sir carbons led to the formation of hissing arcs, and she recommended changes in their design. ''The most efficient arc,'' she concluded in her book, 'would be obtained with infinitely thin carbons and an infinitely short arc" (Ayrtons The Electric Arc, 1902, 389). The engineer must weigh this ideal case against the tendency for thin carbons to produce hissing arcs and bunn out rapidly.

Ayrton's book on the arc was well received. She presented a comprehensive description and analysis of the direct-current arc and showed that her theories would account for the findings of other observers. The book also included a useful historical survey and bibliographies.

Her work led to improvements in the size, shape, and positioning of searchlight carbons. Upon her recommendation the British Admiralty shaped carbon electrodes to the foam they would acquire during steady bunking, thus decreasing the time required for this to occur. She also designed improved carbons and lamp houses for cinema projectors. Ayrton took out eight patents between 1913 and 1918 (Mather 1923).

Ayrton made original contributions to hydrodynamics in her studies of sheave motion and water vortices. She applied these results to air vortices in her invention of the Ayrton fan. Her work was finally rooted in the engineering tradition. She was not motivated or guided by theoretical physical models or by questions of broad theoretical significance. Her education had not prepared her for such an approach. Ayrton's concrete approach and analytical style suited her interests and was appropriate for an engineer of her time. Perhaps her most lasting contribution was to be a role model for other women and to open professional doors a little wider for them.


Works by Hertha Marks Ayrton
Scientific Works

Works about Hertha Marks Ayrton

Other Reference

From L.S. Grinstein, Rose K. Rose and M. H. Rafailovich (eds.), Women in Chemistry and Physics, Westport, CT: Greenwood Press, 1993.