1862 - 1935

Pioneer of surface tension research

Agnes Pockels made important discoveries regarding surface tension and other physicochemical effects.

Her brother, namesake of the Pockels effect, is still well known until this day. The fact that his older sister Agnes was a pioneer of surface science, however, is almost completely forgotten. Initially inspired by observations of dishwater, she started investigating the surface tension of water and its boundary layers at the age of 19.

Even though she had strong interests in natural sciences and attended the high school for girls in the northern German town Braunschweig, it was impossible for her to attend university at that time. Instead, she was bound to stay home and care for her sickly parents.

However, her brother Friedrich studied physics, became a professor, and provided her with scientific literature along the way. In between house and care work, Agnes Pockels researched autodidactically and conducted experiments at home. She invented the so-called "Schieberinne", the predecessor of the still used "Langmuir trough". With this apparatus, she could change the investigated liquid's surface and precisely measure its surface tension.

After German professors had failed to acknowledge her work, she directly wrote to the well-known English scientist Lord Rayleigh. He had conducted similar research to hers and was impressed by her groundbreaking work. Immediately, he submitted her letter to the journal Nature, where Pockel's first article was published shortly after.

Now, after ten years of solitary work and aged 29, she was finally getting the scientific recognition she deserved. Throughout her life, some more publications followed, even though her capabilities to conduct research were limited by money and time she spent taking care of her parents or being ill herself.

Towards the end of her life, the technical university Carolo-Wilhelmina of Braunschweig awarded her with an honorary doctorate in 1932. Today, the same university has a student lab called "Agnes Pockels Labor", enabling pupils to experience natural sciences and honoring Agnes Pockel's fundamental contributions to surface science.

Written by: Katharina Kolatzki.