Barber's pole

A barber's pole is a type of sign used by barbers to signify the place or shop where they perform their craft. The trade sign is, by a tradition dating back to the Middle Ages, a staff or with a helix of colored stripes (often red and white in many countries, but usually red, white, and blue in the United States). The pole may be stationary or may revolve, often with the aid of an electric motor.

A "barber's pole" with a helical stripe is a familiar sight, and is used as a secondary metaphor to describe objects in many other contexts. For example, if the shaft or tower of a lighthouse has been painted with a helical stripe as a daymark, the lighthouse could be described as having been painted in "barber's pole" colors.

During medieval times, barbers performed surgery on customers, as well as tooth extractions. The original pole had a brass wash basin at the top (representing the vessel in which leeches were kept) and bottom (representing the basin that received the blood). The pole itself represents the staff that the patient gripped during the procedure to encourage blood flow.

At the Council of Tours in 1163, the clergy was banned from the practice of surgery. From then, physicians were clearly separated from the surgeons and barbers. Later, the role of the barbers was defined by the , established by Jean Pitard in Paris circa 1210, as academic surgeons of the long robe and barber surgeons of the short robe.

After the formation of the United Barber Surgeon's Company in England, a statute required the barber to use a blue and white pole and the surgeon to use a red pole. In France, surgeons used a red pole with a basin attached to identify their offices. Blue often appears on poles in the United States, possibly as a homage to its national colors. Another, more fanciful interpretation of these barber pole colors is that red represents arterial blood, blue is symbolic of venous blood, and white depicts the bandage.

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