Design
The experiment consists of two brass bells, each positioned beneath a dry pile (a form of battery), the pair of piles connected in series. A metal sphere approximately 4 mm in diameter is suspended between the piles, and rings the bells by means of electrostatic force. As the clapper touches one bell, it is charged by one pile, and then electrostatically repelled, being attracted to the other bell. On hitting the other bell, the process repeats. The use of electrostatic forces means that while high voltage is required to create motion, only a tiny amount of charge is carried from one bell to the other, which is why the piles have been able to last since the apparatus was set up. Its oscillation frequency is 2 hertz.
Probably the most interesting part of the bell is the pair of dry piles. Nobody is certain what they are composed of, but it is known that they have been coated with molten sulphur to prevent effects from atmospheric moisture and it is thought that they may be Zamboni piles.
At one point this sort of device played an important role in distinguishing between two different theories of electrical action: the theory of contact tension (an obsolete scientific theory based on then-prevailing electrostatic principles) and the theory of chemical action.
The Oxford Electric Bell does not demonstrate perpetual motion. The bell will eventually stop when the dry piles are depleted of charge – that is, if the clapper does not wear out first.
Read more about this topic: Oxford Electric Bell
Famous quotes containing the word design:
“We find that Good and Evil happen alike to all Men on this Side of the Grave; and as the principle Design of Tragedy is to raise Commiseration and Terror in the Minds of the Audience, we shall defeat this great End, if we always make Virtue and Innocence happy and successful.”
—Joseph Addison (1672–1719)
“For I choose that my remembrances of him should be pleasing, affecting, religious. I will love him as a glorified friend, after the free way of friendship, and not pay him a stiff sign of respect, as men do to those whom they fear. A passage read from his discourses, a moving provocation to works like his, any act or meeting which tends to awaken a pure thought, a flow of love, an original design of virtue, I call a worthy, a true commemoration.”
—Ralph Waldo Emerson (1803–1882)
“Humility is often only the putting on of a submissiveness by which men hope to bring other people to submit to them; it is a more calculated sort of pride, which debases itself with a design of being exalted; and though this vice transform itself into a thousand several shapes, yet the disguise is never more effectual nor more capable of deceiving the world than when concealed under a form of humility.”
—François, Duc De La Rochefoucauld (1613–1680)