Brustwerk (breast division)
An organ division placed directly above the console, in the case's "breast."
What it means
The Brustwerk is a division of the organ whose pipes are housed directly above the console, in the so-called "breast" of the case. From there it speaks especially directly and closely toward the seated organist and the front rows of listeners.
Musical use
Historically, particularly in North German Baroque organs, the Brustwerk complemented the larger divisions such as the Hauptwerk, Rückpositiv, and Pedal with its own tone color, usually controlled from its own manual, often used for finer, soloistic registrations.
The Brustwerk should be distinguished from the Rückpositiv, positioned behind the organist's back on the gallery rail, and from the Swell organ of later instruments, whose pipes sit in a box with movable shutters for dynamic control.