For those for whom watching paint dry or grass grow is a little too riveting, welcome to the mind-bogglingly slow world of Thomas Parnell’s pitch drop experiment.
A physicist at the University of Queensland in Brisbane, Australia, Professor Parnell wanted to demonstrate to his students that everyday materials can have quite surprising properties. He chose pitch, a tar-like substance which at room temperature may feel and look solid but is in fact a very high viscosity fluid.
Parnell began by pouring a heated sample of pitch into a sealed glass funnel. That was in 1927. For the next three years he let it settle, before cutting the sealed stem of the funnel, allowing the pitch to flow. It took a little over eight years for the first drop to fall, but fall it did, followed by a second in 1947 and a third in 1954.
To date nine drops of pitch have been formed but, frustratingly, no one has yet witnessed the magical moment – or more accurately tenth of a second – that it takes a drop to fall. In 2000, a webcam which had been set up to capture the eagerly anticipated eighth drop suffered a power outage at precisely the wrong moment, while in 2014, the ninth drop didn’t so much fall as snapped during a beaker change.
The good news is that there’ll be plenty more chances to see history in the making. According to experts, there’s still enough pitch left in the funnel to keep viewers enthralled for at least another hundred years. Watch all the action here.
