Helen Klaassen Explained

Helen Gertrude Klaassen (fl. 1893–1919) was an English physicist.

She was the daughter of Hendericus Klaassen, a geologist who had emigrated from Prussia in the 1840s. Her sister was botanist Henderina Scott.

She attended the University of Cambridge, carrying out electrochemical experiments at the Cavendish Laboratory in the late 1880s and 1890s. At the suggestion of J. J. Thompson, she studied electric resistance curves in sulphuric acid.^[1]

She worked as lecturer in physics at Newnham College, Cambridge, and as a demonstrator in physics at the Balfour Biological Laboratory for Women in 1891–1901.^{[2] [3]}

Her most notable work was a collaboration with Alfred Ewing on the magnetic properties of iron, published by the Royal Society of London in 1893.

Klaassen was a member of the National Union of Scientific Workers^[4] and also took an interest in nursing.^[5]

Select publications

• (with James Alfred Ewing) 'Magnetic qualities of iron,' Philosophical Transactions of the Royal Society of London 184 (1893) 985–1039^[6]
• 'Change of phase on reflexion at the surface of highly-absorbing media,' London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science 44 (1897) 349–355^[7]

Notes and References

1. Gould . Paula . 1997 . Women and the Culture of University Physics in Late Nineteenth-Century Cambridge . The British Journal for the History of Science . 30 . 2 . 127–149 . 10.1017/S0007087497002987 . 4027714 . 0007-0874.
2. Book: Gibson, Susannah . The Spirit of Inquiry: How one extraordinary society shaped modern science . 2019-02-14 . Oxford University Press . 978-0-19-256987-5 . 188 . en.
3. Richmond . Marsha L. . 1997 . "A Lab of One's Own": The Balfour Biological Laboratory for Women at Cambridge University, 1884-1914 . Isis . 88 . 3 . 422–455 . 10.1086/383769 . 236151 . 9450359 . 0021-1753.
4. 1919 . Trade Unions Make the World a Better Place . British Journal of Nursing . 63 . 301.
5. 7 May 1910 . Maternity Clubs . British Journal of Nursing . 44 . 374.
6. 1893-12-31 . XIX. Magnetic qualities of iron . Philosophical Transactions of the Royal Society of London. (A.) . en . 184 . 985–1039 . 10.1098/rsta.1893.0019 . 0264-3820. free . 1893RSPTA.184..985E . Ewing . J. A. . Klaassen . Helen G. .
7. Klaassen . Helen G. . 1897 . XLIV. Change of phase on reflexion at the surface of highly-absorbing media . The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science . en . 44 . 269 . 349–355 . 10.1080/14786449708621074 . 1941-5982.