An inductor, also called a coil or reactor, is a passive two-terminal electrical component that stores electrical energy in a magnetic field when electric current is flowing through it. An inductor typically consists of an electric conductor, such as a wire, that is wound into a coil. When the current flowing through an inductor changes, the time-varying magnetic field induces a voltage in the conductor, described by Faraday's law of induction. According to Lenz's law, the direction of induced electromotive force (e.m.f.) opposes the change in current that created it.
Designated a National Historic Landmark in 1963, the park is currently managed by the Central Park Conservancy under contract with the city government. The Conservancy is a nonprofit organization that contributes 85% of Central Park's $25 million dollar annual budget, and employs 80% of the park's maintenance staff.
In 1867, Central Park designer and architect Calvert Vaux (1824-1895) created an observation tower atop Vista Rock to overlook the old reservoir that is now the Great Lawn. The Gothic-style Castle was designed as a landmark for the pedestrian park visitor.