Begun in 1927 at The University of Queensland, Australia, the pitch-drop experiment is an attempt to prove that pitch (a sticky, black, seemingly solid form of petroleum) is actually just a particularly viscous liquid. It takes years for a drop of pitch to form and, until this week, nobody had ever observed the drops in the act of, well, dropping. The catch: It wasn’t the University of Queensland that finally succeeded. Instead, the documentary footage comes from a different (and less famous) pitch-drop experiment at Trinity College, Dublin, Ireland. You can watch the drop drip in a video at their site.