It took them 69 years, but scientists finally caught a drop of black pitch falling on camera.
The tar pitch has been moving slowly through the funnel since 1944, and this is the first time it has ever been caught dropping on camera, a Trinity University press release reported.
The pitch only drops about once every decade, a similar experiment's research team missed theirs drop back in 2000 because the camera was offline.
The purpose of the experiment was to prove pitch can flow, even though it does so extremely slowly. Scientist had previously believed the substance was a solid, the study proved it is in fact liquid.
Researchers at Trinity College calculated the viscosity of the substance to be 2x107 Pa s, which is around two million times thicker than honey.
"People love this experiment because it gets to the heart of what good science is all about - curiosity. Over these past few months, there has been constant chat about when the drip would drop. I watched the time lapse video of the pitch drop falling over and over again. I was amazed. This was the first time this phenomenon was ever witnessed!" Professor Shane Bergin, who participated in the study said.
The same experiment at University of Queensland was set up in 1927, and holds the Guinness world record for longest running experiment. Eight drops have fallen over the course of the experiment; nobody has ever witnessed it, until now.
Professor John Mainstone has been eager to see pitch move, after missing the last drop back in 2000, the Daily Mail reported.
"The closest I have been to seeing a drop live is five minutes away, and on another occasion I left the university thinking it would not drop at least until the next day, but when I arrived in the morning it had happened," Mainstone said.
The welcomed sighting marks the first solid proof that pitch is a very thick liquid.
"We were all so excited; it's been such a great talking point, with colleagues eager to investigate the mechanics of the break, and the viscosity of the pitch," Bergin told Nature.
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