Longest Experiment in History

in this video Prakash explain in tamil about "pitch drop experiment " longest experiment in the world. In 1927, a physics professor set up an experiment to prove that pitch, which breaks like glass, is actually a liquid. It took three years just to prepare and eight years for the first drop to fall. Nearly a century later, only nine drops have fallen, proving pitch is 20 billion times thicker than water. The experiment is still running today, and you can even watch the next drop live.