Black Rod 1350 by royal letters patent, though the current title dates from 1522. The position was adopted by other members of the Commonwealth when they adopted the British Westminster system. The title is derived from the staff of office, an ebony staff topped with a golden lion, which is the main symbol of the office's authority. A ceremonial rod or staff is a common type of symbol indicating the authority of the office-holder. Depictions of ancient authority figures in many cultures include such a rod (alternatively called a sceptre). Another early example was the fasces (literally a bound bundle of rods)
Caduceus as a symbol of medicine popularised the caduceus, whilst retaining the caduceus for its own plaque and insignia, is now part of the Army Medical Department, which has since adopted the Rod of Asclepius as its main symbol. Furthermore, when the U.S. Air Force designed new medical insignia, it also adopted the rod of Asclepius. (The Royal Air Force (UK) medical services have, however, used the caduceus as uniform collar insignia since the foundation of the RAF in 1918.) Despite widespread acceptance of the caduceus as a medical symbol in the United States, it has been observed that the rod of Asclepius has "the more