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
Highfield lever about 1930. http://www.ybw.com/cb/gloss.html#Highfield https://books.google.com/books?id=Fp63wWByImQC&pg=PA145&lpg=PA145&dq=%22Highfield+lever%22&source=web&ots=dtOvGn79kw&sig=vDH04nBiAXxluXvIdcGcUdh3i_U&hl=en&sa=X&oi=book_result&resnum=3&ct=result Highfield lever A Highfield lever is a lever device which allows tension to be rapidly set up in a wire and equally rapidly released to the required extent. It is frequently used in sailing boats where tension in some part of the rigging needs to be adjusted to a pre-set amount as the wind impinges on one side of the sails or the other. It is typically used in running backstays (runners). To make it work, the backstay is led through a block or fairlead along the deck to a two-legged, second order lever mounted with