Smelling salts
Smelling salts, also known as ammonia inhalants, spirit of hartshorn or sal volatile, are chemical compounds used for arousing consciousness.
The usual active compound is ammonium carbonate—a colorless-to-white, crystalline solid ((NH4)2CO3). Because most modern solutions are mixed with water, they should more properly be called "aromatic spirits of ammonia." Modern solutions may also contain other products to perfume or act in conjunction with the ammonia, such as lavender oil or eucalyptus oil.
Historically, smelling salts have been used on people feeling faint, or who have fainted. They are usually administered by others, but may be self-administered; some at-risk groups, such as pregnant women, may be advised to keep them close to hand.
Smelling salts are often used on athletes (particularly boxers) who have been dazed or knocked unconscious to restore consciousness and mental alertness. Smelling salts are now banned in most boxing competitions.
They are also used as a form of stimulant in athletic competitions (such as powerlifting, strong man and ice hockey) to "wake up" competitors to perform better. In 2005, Michael Strahan estimated that 70 to 80 percent of National Football League players were using smelling salts as stimulants.
Smelling salts have been used since Roman times and are mentioned in the writings of Pliny as Hammoniacus sal. Evidence exists of use in the 13th century by alchemists as sal ammoniac. In the 14th century's The Canterbury Tales, a character purports to use sal armonyak. In the 17th century, the distillation of an ammonia solution from shavings of harts' (deer) horns and hooves led to the alternative name for smelling salts as spirit or salt of hartshorn.
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