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Webcast: Pitch Drop Experiment Nears Ninth Drop

The University of Queensland is offering people around the world the chance to add their name to the world's longest running laboratory experiment, the Pitch Drop.

The experiment was established in 1927 to demonstrate the high viscosity of pitch, which looks like a solid but behaves like a fluid over an extended timeframe.

The Pitch Drop Experiment is basically a lump of pitch in a glass funnel.

Eight drops of pitch have fallen in 86 years, but no-­one has ever seen one fall.

A new website,, will log watchers from all time zones to record who is logged in when the ninth Pitch Drop falls.

With signs of the stem narrowing, the ninth drop is set to fall at any time.

The Ninth Watch is dedicated to Professor John Mainstone, who was Pitch Drop custodian for 52 years until he died in August without seeing a drop fall.

“It will be possible for them to be part of history,” he said in July this year, referring to the large base of Pitch Drop fans from around the world.

Professor Andrew White is the Pitch Drop's new custodian.

“The names of people logged in to the site when it falls, and their observations, will be added to the official records, so it's their shot at immortality,” Professor White said.

The Pitch Drop has eluded the world and its custodians.

In 1988 a drop fell when Professor Mainstone left the experiment for five minutes to get a drink.

In 2000 the Pitch Drop was on webcam surveillance – but the camera failed and the drop fell.

“The Pitch Drop has a mind of its own,” Professor Mainstone said at the time.

Professor White said Professor Mainstone would have been "tickled pink" that there was now potential for dozens or even hundreds of people to see the next drop fall.

“I think he would love that."

Labelled the world's oldest and possibly most boring experiment, the Pitch Drop has captured the attention of hundreds of thousands of citizen-­scientists and has been recognised with a Guinness Record and an Ig Nobel Prize.

The Ninth Watch for the ninth drop has an upgraded live feed streaming in high resolution for clear observations from around the world.

Author Nick Earls, who included the Pitch Drop in his novel ‘Perfect Skin', has his own hopes for the ninth drop.

“I kind of hope it's going to elude us again, however good our technology, because that's part of its mystique,” he said.

“But if there's someone in Angola who happens to be online with a good internet connection and goes ‘yep, I was there and I saw it,' I think that would be quite nice.”

University of Queensland