Initial findings Through her experiences carrying out domestic chores, especially dishwashing, Pockels became interested in the effect of soaps on water and more generally on the effect of impurities on water and soapy water. By age 18, she began conducting experiments in her home to understand the physical properties of water and impurities, as an
amateur chemist. Pockels further developed her apparatus by placing a small disk (typically 6 millimeters in diameter), such as a
button, on the surface of the water in the trough. She then used a
weighing scale (typically an
apothecary's balance) to determine the force (
weight) necessary to lift the disk from the water. By comparing the forces required to lift the disk from pure water to water containing impurities, she devised a direct measure of surface tension. This apparatus enabled her to investigate the surface forces of mono-molecular films, the surface tension of emulsions and solutions, the effect of impurities on the physical properties of water, and providing an understanding of surfactancy. Pockels' design influenced later investigators who improved on the method, leading to the modern
Langmuir–Blodgett trough which is in extensive use in colloid and surface science in contemporary times. Her first paper was "Surface Tension," describing her measurements and findings with her sliding trough. The letter to Lord Rayleigh was described in a 1971 journal article on the origin of the surface film balance as being "a landmark in the history of surface chemistry". Pockels described the calming effect that oils can have on bodies of water, Her research extended to investigations of other surface phenomena including
capillarity and
contact angles. She was eventually recognised as a pioneer in the emerging field of
surface science. Following the death of her brother, Friedrich Carl Alwin Pockels in 1913 and her own ill health, Agnes Pockels lost contact with many professional scientists and ceased to undertake original research. ==Personal life==