Sometimes science can be painfully slow. Data comes in dribs and drabs, truth trickles, and veracity proves viscous.
The world's longest-running lab experiment is an ongoing work in sheer scientific patience. It has been running continuously for nearly a century, under the close supervision of several custodians and many spectators – and it's ever so slowly drip, drip, dripping away.
It all started in 1927, when physicist Thomas Parnell at the University of Queensland in Australia filled a closed funnel with the world's thickest known fluid: pitch, a derivative of tar that was once used to seal ships against the seas.
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Three years later, in 1930, Parnell cut the funnel's stem, like a ribbon at an event, heralding the start of the Pitch Drop Experiment. From then on, the black substance began to flow.
At least, that is, in a manner of speaking. At room temperature pitch might look solid, but it is actually a fluid 100 billion times more viscous than water.
It took eight years for the first droplet to finally hit the beaker below. Then, they dripped at a cadence of once every eight years or so, slowing down only after air conditioning was installed in the building in the 1980s.
Today, 96 years after the funnel was cut, only nine drops in total have seeped out. The last was in 2014.
Scientists expect another will fall sometime in the 2020s, but they are still waiting.
No one has ever actually seen a droplet fall directly, despite all the watchful eyes. The experiment is now live-streamed, but various glitches in the past meant that each fateful moment has slipped us by.
After Parnell, fellow physicist John Mainstone took over caretaking duties in 1961. Sadly, both died without ever seeing a droplet fall with their own two eyes.
Mainstone was custodian for 52 years. In 2000, he missed a drop because a thunderstorm disrupted the live feed. He passed away just a few months before the next drop oozed out in April 2014.
Physics professor Andrew White is the third and current custodian of the pitch drop experiment, keeping vigil for the long-awaited 10th drop.
The world's longest-running lab experiment has barely begun.