Custodian of pitch drop experiment dies
The custodian of the world’s longest running laboratory experiment, Professor John Mainstone, has died at the age of 78 after suffering a stroke. The former Head of the University of Queensland’s (UQ) Department of Physics was the guardian of the world-famous pitch drop experiment.

The pitch drop experiment was established in 1927 by Professor Thomas Parnell to demonstrate the fluidity and high viscosity of pitch, a derivative of tar once used to waterproof boats.
At room temperature pitch feels solid - even brittle - and can easily be shattered with a blow from a hammer but, surprisingly, it acts like a fluid. Three years after the commencement of the experiment, the glass funnel holding the pitch was cut to allow the pitch to ‘flow’.
Only eight drops have fallen in the 83 years since the pitch began dripping. Professor Mainstone was custodian of the experiment for 52 years and neither he, nor anyone else, has ever seen a drop fall.
UQ’s Head of the School of Mathematics and Physics, Professor Halina Rubinsztein-Dunlop, said, “Professor Mainstone’s dedication to the long-running experiment well past his official retirement ensured that media, researchers and undergraduate students had easy access to relevant information and an understanding of the important science behind it.”
She added that Professor Mainstone maintained an office and close connection to the university up until his death.
The experiment is now under constant surveillance, with three webcams trained on it to capture the ninth drop’s fall on camera. The live feed of the experiment can be viewed at www.smp.uq.edu.au/content/pitch-drop-experiment.
Air quality expert wins 2025 PM's Prize for Science
Distinguished Professor Lidia Morawska's work in the study of air quality provided vital...
CSL fellowships fund immunity research, AI-designed proteins
Australian scientists Dr Carolien van de Sandt and Dr Rhys Grinter have each been awarded CSL...
Leukaemia Foundation funds ongoing blood cancer research at UWA
The $3m in funding is understood to represent the single largest non-government investment in...

