It's as common a sight in business districts as street lamps or parking spaces: a revolving vertical tube that signals a destination for patrons in need of a haircut or shave. It's the barber pole, and it usually materializes with a red-, white-, and blue-striped color scheme.

It would be fair to guess that the design has something to do with patriotism. The truth, however, isn't so heartwarming.

The dual arts of cutting hair and shaving faces have been around for a very long time, as have the barbers who practice them: Razors dating from the Bronze Age have been found, and the "barber's razor" is even mentioned in the Bible. For much of their early history, barbers did much more than just take a little off the top; early physicians thought of some surgeries as being beneath them, so the tasks of mending wounds, bloodletting, and extracting teeth fell to barbers. For their dual roles of cutting hair and cutting veins, they were called barber-surgeons and later, when the Collège de Saint-Côme in Paris wanted to further distinguish between academic surgeons and barber-surgeons, "surgeons of the short robe."

The striped poles you see outside barber shops are a legacy of the barber-surgeons' practice of bloodletting. The typical barber-surgeon's equipment for bloodletting or applying leeches consisted of a staff (for the patient to grasp, causing the veins of the arm to stand out sharply), a basin (to catch blood and hold leeches), and a number of linen bandages. Often, the bandages were tied to or twisted around the staff, which was capped with the blood bowl, so everything was together when needed. The equipment would then be placed outside, both to dry washed bandages and to act as an advertisement. With the help of a stiff breeze, the bandages—clean in some spots, permanently stained in others—would twist around the pole and create an unmistakable swirling red and white pattern.

Over time, bloodletting fell out of practice, and the tools of the trade disappeared from barbers' shops as they concentrated on hair. (Some stubbornly continued to practice medicine; in 1745, England passed legislation to permanently separate barbers from surgeons.)

To maintain tradition and advertise their services with a recognizable symbol, many barbers placed wooden poles outside their shops, which they painted with stripes and topped with a ball, to resemble the staff/bandage/basin arrangement. The red represented the blood, the white the bandages, and the blue the protruding veins. The modern barber pole was born.

Many of today's poles feature rotating, light-up cylinders and weather-resistant plastic and steel parts. Most of these poles probably came from the William Marvy Company of St. Paul, Minnesota, which has, for decades, been the dominant producer of barber poles in America. Company founder William Marvy got his start as a barber supply salesman in the 1920s. He was convinced that he could produce a better barber pole than the ones he'd been pushing, so he launched his own company. By 1950, he had perfected his version of the barber pole. The Marvy model featured a Lucite outer cylinder, cast aluminum housing, and stainless steel fittings, making it lighter, sturdier, and more durable than the other poles available.

By the late 1960s, two of Marvy's competitors had gone out of business, and his other two rivals were farming out their pole manufacturing to his factory. Soon enough, the Marvy Company was the only game in town, and in the country.

William Marvy, the only non-barber in the Barber Hall of Fame, died in 1993, but the company is still going today under the direction of his son, Bob. Annual pole sales are down to about 600 (compared to 5100 in 1967), but the company keeps itself busy selling replacement parts and grooming supplies and restoring old poles. If you're in the market for one to advertise your styling or bloodletting services, they still offer several different revolving and stationary models.

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