Bellows

For other uses, see Bellows (disambiguation).
Diagram of a fireplace hand-bellows

A bellows or pair of bellows is a device constructed to furnish a strong blast of air. The simplest type consists of a flexible bag comprising a pair of rigid boards with handles joined by flexible leather sides enclosing an approximately airtight cavity which can be expanded and contracted by operating the handles, and fitted with a valve allowing air to fill the cavity when expanded, and with a tube through which the air is forced out in a stream when the cavity is compressed.[1] It has many applications, in particular blowing on a fire to supply it with air.

Hand-made English fireplace bellows

The term "bellows" is used by extension for a flexible bag whose volume can be changed by compression or expansion, but not used to deliver air. For example, the light-tight (but not airtight) bag allowing the distance between the lens and film of a folding photographic camera to be varied is called a bellows.

  1. ^ "bellows". Oxford English Dictionary (Online ed.). Oxford University Press. doi:10.1093/OED/2579804254. (Subscription or participating institution membership required.)