When Sir Robert Peel formed the London Metropolitan Police Force in 1829, part of each Bobby's kit was his rattle.

The rattle was not a new invention, although it has had dozens of names; the ratchet, the noisemaker (still in use as the football rattle), the gragger (Yiddish) or ra'ashan (Hebrew), the cog rattle, and the raganella, among others. They consist of a cog wheel set in a frame to which a flexible, usually wooden, tongue is affixed; when the cog revolves the tongue snaps along the teeth of the cog. They are usually designed to used by means of a handle attached to the axis of the cog, which is then swung around allowing the tongue encasement to swing freely around the cog. This can be surprisingly loud.

The Victorian police rattles were made to be as loud as possible, as they were used to call for help or alert the neighborhood to trouble. They were large, about the size of a shoe, and made to fold up and fit into tailored pockets in one of the swallow-tails of their tailcoats (the other tail contained their truncheon). They were also weighted with lead, providing both extra weight to aid in strong rotation, and to allow them be used as a club if necessary.

The police rattle was replaced by the simpler, lighter, and louder police whistle in the 1880s. Rattles didn't die out entirely, as they were also used by fire brigades, and later were used as gas-attack alarms by soldiers during WWI. During a gas attack the wise soldier would be wearing his gas mask as soon as he saw a need to raise the alarm, making whistles impractical; the rattle proved to be a cheap, effective, and distinctive solution. These days, however, rattles are primarily recognized as noisemakers, and are most often seen at football matches.