The Longest Experiment

I opened this blog with the world's longest living thing, now I have an interesting fact concerning its longest experiment. The obvious answer may be something like M Night Smymalan's career as a director, 'Okay chaps, we tried it for a while with only a few positive results, clearly it is not working as a long term plan, let's just end it now.'
It began in 1840 but it may have actually lasted longer than that, with evidence suggesting that it may have started as early as 1825. It is also still going to this day. It is in fact a battery, in Oxford. This contraption contains two domes and a climber. The idea being that when one climber hits the dome it causes the charge to be transferred to the other one.
The point of this? To see how long the battery lasts, and the answer is quite a while. This process has been run ten billion times over the course of its life and estimates indicate that the battery will keep going for 350 years, so we've got a long time before it ceases to do whatever it does yet. The main problem with this is that no one is sure what it is made of due to the fact that its inventor failed to take notes during the building of the device.