A Test of Patience

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image courtesy of Professor J S Mainstone, The University of Queensland

Imagine that you are waiting for an extraordinary moment, the moment of your life: marriage to your true love, or the birth of your child. We are used to waiting for momentous occasions, but rarely for more than a year or two: Plans projected too far into the future elude our ability to conceptualize realization of them. When it comes to scientific experiments, however, expectations are sometimes framed within a different temporality. Sometimes very different.

The Pitch Drop Experiment was initiated in 1927 by Thomas Parnell, a professor at the University of Queensland in Brisbane, Australia, to demonstrate for his students that some substances that appear to be solid are actually fluid. He poured a heated sample of pitch, a naturally occurring petroleum substance that is brittle at room temperature, into a funnel-shaped glass container, which he sealed. After three years, the sample had settled. It was time to kick-start what is now the longest-running and what must surely be one of the slowest laboratory experiments in history.

Parnell unsealed the funnel and the pitch was free to flow. After a couple of years, a drop began to form. It took eight years for it to fall. The student audience of the experiment continued, nevertheless, and every eight or so years, a little baby drop left the nest of mama pitch above for the growing expanse of papa pitch below. After the eighth and most recent drop fell on November 28, 2000, the viscosity of pitch was finally calculated to be one hundred billion times that of water.

To date, no one has ever witnessed a drop fall. There is no visual documentation of the dramatic event. The closet anyone ever came was in April 1979 when John Mainstone, the professor who now maintains the experiment, came to work on a Sunday afternoon. He noted that a drop was just about to touch down, but did not have time to stay. On returning the following morning, Mainstone saw to his chagrin that the drop had fallen. Even technology has been foiled in the attempt to capture evidence of the pitch’s clandestine maneuvers: A video camera placed to monitor the experiment failed at the very moment the eighth drop fell.

Given an average interval of about eight and a half years between each drop, the pitch–now nine years pregnant with its current drop–might be expected to give birth any day. As it turns out, however, the intervals between drops have lasted anywhere between seven and twelve years. The funnel’s location in the foyer of the physics department leaves it particularly susceptible to environmental effects, and the twelve-year span between the past two drops can be explained by the fact that air-conditioning was installed in the building. It could turn out that my daily habit of checking in on the current drop via the webcam might go on for a while.

Though nothing really happens, as an act of resistance against the rapid flow of time the experiment is a great success, the pitch transformed from a physical substance to be scientifically investigated into a metaphysical monument to suspended anticipation.

Excerpted from the “Testing” issue of Cabinet (Summer 2009), an unapologetically intellectual quarterly that explores art and culture within the margins of inventive themes.

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