world's longest experiment

• We will present to you three examples that are considered to be the world's longest experiments, although they can be argued and you can even go as far back and say the creation of the Universe was just an experiment.
  
  First we have the Pitch Drop Experiment started in 1927 by Thomas Parnell. Basically he poured some pitch (a derivative of tar) into a funnel and let it drip out the bottom.
  
  It took 3 years just for the pitch to settle and the first drop finally fell in 1938. The experiment is still ongoing at the Department of Physics at the University of Queensland in Brisbane and in November 2000 only the 8th drop fell.
  
  Secondly is the Beverly Clock located at the Department of Physics at the University of Otago. The clock was made by Arthur Beverly and has not needed winding since it was made in 1864.
  
  Finally, at the Clarendon Laboratory at the University of Oxford we have the Oxford Electric Bell that has been ringing continuously since 1840. The bell is powered by two batteries coated in sulphur, but no one knows what they are made of. The bell shows no signs of stopping and the clapper will likely wear out before the batteries do.