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The bellows behind the keyboard show that this is a type of organ, yet it has no pipes. Instead, this instrumen produces sound using small metal reeds which are inside the keyboard. When the bellows are pumped, air flows across the reeds causing them to vibrate. The sound is distinctive, almost brash.This instrument is a type of portable organ known as a regal, and specifically a “bible regal”. When not in use, the organ may be folded up: the keyboard fits inside one of the bellows which then close together to look like a wooden-bound bible. This kind of small organ seems to have come into use in the 15th century, and remained in use for about 300 years. Monteverdi specifically requests the use of a regals as a continuo instrument in his opera Orfeo (1605). (Galpin Society Collection).