World's longest Continuously Running Experiment - Pitch drop

Pitch drop experiment - Pitch is the name for any of a number of highly viscous liquids that appear solid, most commonly bitumen and this long-term experiment measures the flow of a piece of pitch over many years. It was started in 1927 by Professor Thomas Parnell in Australia.

This is recorded in Guinness World Records as the world's longest continuously running laboratory experiment and it is expected that there is enough pitch in the funnel to allow it to continue for at least another hundred years.

More Info at WikiPedia