<P> Ornamentation, such as bows or buckles, are attached on the left side . Historically this had a practical purpose . Because the majority of people are right - handed, in the absence of a wide brim, bows or feathers on the right side of headwear could interfere with the use of weapons . </P> <P> Inside the cowboy hat is a memorial bow to past hatters, who developed brain damage from treating felt with toxic mercury (which gave rise to the expression "Mad as a hatter"). The bow on the inside hatband at the rear of the hat resembles a skull and crossbones . "Early hatters used mercury in the making of their felt . Their bodies absorbed mercury, and after several years of making hats, the hatters developed violent and uncontrollable muscle twitching . Lack of medical knowledge caused people to attribute these strange gyrations to madness, not mercury ." </P> <P> The modern cowboy hat has remained basically unchanged in construction and underlying design since the Stetson creation . The cowboy hat quickly developed the capability, even in the early years, to identify its wearer as someone associated with the West . "Within a decade the name "John B. Stetson" became synonymous with the word "hat" in every corner and culture west of the Mississippi ." The shape of the hat's crown and brim were often modified by the wearer for fashion and to protect against weather by being softened in hot steam, shaped, and allowed to dry and cool . Felt tends to stay in the shape that it dries . Because of the ease of personalization, it was often possible to tell where a cowboy hat was from, right down to which ranch, simply by looking at the crease in the crown . </P> <P> Later as the mystique of the "Wild West" was popularized by entertainers such as Buffalo Bill Cody and western movies starring actors such as Tom Mix, the Cowboy hat came to symbolize the American West . John Wayne christened them "the hat that won the West". The Boss of the Plains design influenced various wide - brimmed hats worn by farmers and ranchers all over the United States . Later designs were customized for law enforcement, military and motion pictures . </P>

A felt or straw hat with a wide brim traditionally worn in mexico and south west usa