Percussion instrument

A percussion instrument is a musical instrument that is sounded by being struck or scraped by a beater (including attached or enclosed beaters or rattles); struck, scraped or rubbed by hand; or struck against another similar instrument. The percussion family is believed to include the oldest musical instruments, following the human voice.

The percussion section of an orchestra most commonly contains instruments such as timpani, snare drum, bass drum, cymbals, triangle and tambourine. However, the section can also contain non-percussive instruments, such as whistles and sirens, or a blown conch shell. On the other hand, keyboard instruments, such as the celesta, are not normally part of the percussion section, but keyboard percussion instruments such as the glockenspiel and xylophone (which do not have piano keyboards) are included.

Percussion instruments are most commonly divided into two classes: Pitched percussion instruments, which produce notes with an identifiable pitch, and unpitched percussion instruments, which produce notes or sounds without an identifiable pitch.

Percussion cap

The percussion cap, introduced circa 1820, was the crucial invention that enabled muzzleloading firearms to fire reliably in any weather. This gave rise to the caplock or percussionlock system.

Before this development, firearms used flintlock ignition systems that produced flint-on-steel sparks to ignite a pan of priming powder and thereby fire the gun's main powder charge (the flintlock mechanism replaced older ignition systems such as the matchlock and wheellock). Flintlocks were prone to misfire in wet weather, and many flintlock firearms were later converted to the more reliable percussion system.

The percussion cap is a small cylinder of copper or brass with one closed end. Inside the closed end is a small amount of a shock-sensitive explosive material such as fulminate of mercury. The percussion cap is placed over a hollow metal "nipple" at the rear end of the gun barrel. Pulling the trigger releases a hammer that strikes the percussion cap and ignites the explosive primer. The flame travels through the hollow nipple to ignite the main powder charge. Percussion caps were, and still are, made in small sizes for pistols and larger sizes for rifles and muskets.

Percussion (disambiguation)

Percussion may refer to: