from Open Culture:
"Begun in October 1944 at Trinity College Dublin’s School of Physics, the Tar Drop experiment has attempted to measure the viscosity of pitch tar, a polymer that seems solid at room temperature. The goal of the experiment? To demonstrate that pitch tar actually flows and to capture a drop falling from a funnel — something that happens about once a decade. Above, you can watch a timelapse video of all the exciting action. It marks the first time a pitch drop has ever been captured on film."