Tettje Clay-Jolles (1881–1972) was one of the first female Dutch physicists. She studied the variation of atmospheric radiation with geographic latitude.

Early life

Clay-Jolles was born in 1881 in

Assen Assen () is a municipality and a city in the northeastern Netherlands, and is the capital (politics), capital of the province of Drenthe. It received City rights in the Netherlands, city rights in 1809. Assen is known for TT Circuit Assen, the ...

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

to Eva Dina Halbertsma and Maurits Aernout Diedrick Jolles. She was the first and only girl to attend the local secondary school, passing both the alpha and beta series exams at the end of her studies there. These exams tested her knowledge of the humanities and science and she passed both, which was reportedly an unusual occurrence.

Education

After secondary school, Clay-Jolles attended the

University of Groningen The University of Groningen (abbreviated as UG; nl, Rijksuniversiteit Groningen, abbreviated as RUG) is a Public university#Continental Europe, public research university of more than 30,000 students in the city of Groningen (city), Groningen in ...

. She commuted each day from

by train until 1903 when she transferred to the

University of Leiden Leiden University (abbreviated as ''LEI''; nl, Universiteit Leiden) is a public research university in Leiden, Netherlands. The university was founded as a Protestant university in 1575 by William, Prince of Orange, as a reward to the city of Le ...

. At the University of Leiden, she was one of the few women who studied physics at the university. There she began her doctoral research on

low-temperature physics In physics, cryogenics is the production and behaviour of materials at very low temperatures. The 13th IIR International Congress of Refrigeration (held in Washington DC in 1971) endorsed a universal definition of “cryogenics” and “cr ...

under

Heike Kamerlingh Onnes Heike Kamerlingh Onnes (21 September 1853 – 21 February 1926) was a Dutch physicist and Nobel laureate. He exploited the Hampson–Linde cycle to investigate how materials behave when cooled to nearly absolute zero and later to liquefy helium f ...

Career

After moving to Java, Clay-Jolles returned to research and worked as an assistant in a laboratory researching vacuum pumps. During this time she also edited and typed all of her husband's publications. In recognition of her expertise as a scientist and scholar, she was hired to edit a series of lectures by Nobel laureate

Hendrik Antoon Lorentz Hendrik Antoon Lorentz (; 18 July 1853 – 4 February 1928) was a Dutch physicist who shared the 1902 Nobel Prize in Physics with Pieter Zeeman for the discovery and theoretical explanation of the Zeeman effect. He also derived the Lorentz t ...

in 1921. Clay-Jolles worked with her husband during the 1920s studying

cosmic ray Cosmic rays are high-energy particles or clusters of particles (primarily represented by protons or atomic nuclei) that move through space at nearly the speed of light. They originate from the Sun, from outside of the Solar System in our own ...

s, radiation in the ultraviolet solar spectrum, and the intensity of atmospheric radiation. The two discovered that atmospheric radiation depended on geographic latitude. They did this by comparing the ultraviolet light at their location in Java to the ultraviolet light at the Batavia Observatory. Clay-Jones and her husband published an article on these findings in the ''Proceedings of the Amsterdam Academy of Sciences'' entitled "Measurements of Ultraviolet Sunlight in the Tropics." After some dispute over the veracity of these findings, Clay-Jolles defended their work in a discussion published in the East Indian scientific journal, ''Natuurkundig Tijdshrift voor Nederlandsch-Indië''.

Personal life

Clay-Jolles met and fell in love with

Jacob Clay Jacob Clay () (January 18, 1882–December 31, 1955) was a prominent Dutch people, Dutch physicist who first suggested and provided evidence that cosmic rays are charged particles. Early life Clay was born "Jacob Claij" in Berkhout on 18 January ...

, another of Kamerlingh Onnes's students, and in 1908 the two were married. Later that year she left school to focus on her family. She spent the next twelve years raising the couple's three children. In 1920, the family moved to

Bandung Bandung ( su, ᮘᮔ᮪ᮓᮥᮀ, Bandung, ; ) is the capital city of the Indonesian province of West Java. It has a population of 2,452,943 within its city limits according to the official estimates as at mid 2021, making it the fourth most ...

, Java when Jacob Clay was hired as a professor of physics at the Institute of Technology. In 1929, the family moved to

Amsterdam Amsterdam ( , , , lit. ''The Dam on the River Amstel'') is the Capital of the Netherlands, capital and Municipalities of the Netherlands, most populous city of the Netherlands, with The Hague being the seat of government. It has a population ...

where Clay-Jones died in 1972.

References

{{DEFAULTSORT:Clay-Jolles, Tettje 1881 births 1972 deaths 20th-century Dutch physicists People from Assen University of Groningen alumni Dutch women physicists 20th-century Dutch women scientists