Compound lever the force of pushing back the stick to the levers and they rub against the wheels, using friction to slow and eventually stop the train. These are everyday applications of this mechanism. A piano key is a compound lever of the first-class, since the fulcrum is between the weight to be moved and the power. The purpose of this lever is to translate a small movement (depression of the key) into a larger and fast movement of the hammer on the strings. The quality of the resulting tone depends on whether the final speed is brought about by gradual or
Lever House project included the addition of marble benches and an Isamu Noguchi sculpture garden to the building's plaza – elements in the original plans for the building which were never realized. In 2003, Lever House Restaurant became the first business to operate as a restaurant at Lever House and later won "New York Magazine"'s Best Service award in 2004. Lever House Restaurant closed in early 2009. As of October 2009, restaurant Casa Lever occupies the former Lever House Restaurant space. Aluminum producer Alcoa is headquartered in Lever House. As of 2005, the building's tenants included Thomas Weisel Partners LLC, which maintains