In 1927, when the University of Queensland was just 18 years old, Thomas Parnell, the school’s first physics professor, set up an experiment. Parnell wanted to show that pitch, a tacky resin made from fat and wood and acid that was once used to waterproof boats was liquid, so he set some out in a funnel to watch it drip. And drip it did…eventually.
For the past 86 years that funnel full of pitch has sat beneath a bell jar. In that entire span of time, the pitch has dripped just eight times. But, says CNN, things seem set to change. A ninth drop is brewing, and according to University of Queensland professor John Mainstone—the man who has tended the experiment for the past 51 years—it could drop any day now. Or, any week now. Or any month. According to CNN, “No-one has witnessed the once-in-a-decade drop.”
“It’s looking like things will happen in a matter of months but for all I know it might be a matter of weeks,” Mainstone tells CNN.
“People think I have got in the habit of sitting alongside it day and night but I do need some sleep,” adding that he normally checks on it five or six times a day and keeps an eye on the web feed from his computer.
In 1979, Mainstone missed the key moment after skipping his usual Sunday campus visit and, in 1988 he missed it by just five minutes as he stepped out “to get a refreshment.”
The last drop — in 2000 — he thought was captured on camera only to find a glitch and nothing on film.
An array of cameras is trained on the drop this time, so hopefully the action can be captured. If you have an exorbitant amount of patience, there is a webcam you can watch live on the University of Queensland’s website.
The demonstration show both the properties of pitch but also offers, says CNN, “a deeper understanding of the passage of time.” The pitch drop has, over time, developed a bit of a cult following.
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