original c. 1924 ornamental cast bronze emblematic interior guest room doorknob and matching backplate salvaged from the historic book cadillac hotel. the doorknob contains a centrally located shield accentuated with a baked polychrome enameled finish. the matching doorknob backplate or escutcheon contains an older yale & towne cylinder lock with functional key. the interior guestroom hardware was fabricated by the sargent hardware co., new haven, ct. the book cadillac hotel was developed by three brothers, j.b., frank, and herbert book. the brothers sought to turn detroit's washington boulevard into the "fifth avenue of the west." part of that vision was the creation of a flagship luxury hotel. they commissioned architect louis kamper to design the building. he had worked with the book brothers in 1917 on the book building. in 1917 they bought the old cadillac hotel at the northeast corner of michigan and washington, but world war i material shortages delayed the start of work on their new hotel. construction finally began in 1923, and, when the building opened in december 1924, it was the tallest building in the city and the tallest hotel in the world. the hotel cost $14 million to build and contained 1,136 guest rooms. public spaces on the first five floors included three dining rooms, three ballrooms, a spacious lobby, and a ground floor retail arcade. on the hotel's top floor was radio station wcx, the predecessor to wjr. the hotel operated successfully until the great depression, when banks foreclosed and the book brothers lost control in 1931. for much of the period after the books lost ownership, the hotel was run by hotel industry pioneer ralph hitz's national hotel management company. in 1951, sheraton bought the hotel, renamed it the sheraton-cadillac, and undertook massive renovations. all public spaces except the ballrooms and italian garden were redone, which included replacing the grand staircase with an escalator. in 1975, with business declining and the hotel in need of another renovation, sheraton sold the hotel, and it became the detroit-cadillac. ownership changed again in 1976, and it became the radisson-cadillac. in 1979 the radisson chain sold it, and it became the book-cadillac once again. though it was considered the city's top hotel for many years, its occupancy had fallen off significantly by this point, and the owners announced that the hotel would close. priced for the knob and backplate. height 12" x width 2". knob diameter 2-1/4".