"Bagpipes are a class of musical instrument, aerophones using enclosed reeds....A bagpipe minimally consists of an air supply, a bag, and a chanter. Optionally, further chanters and/or drones can be added....A more recent innovation, dating from the 16th or 17th centuries, is the use of a bellows to supply air. This has the advantage that the supplied air has not been heated and moistened by the player's breathing. Bagpipes using bellows can therefore use more refined and/or delicate reeds." http://en.wikipedia.org/wiki/Bagpipe
Chart showing the number of references in each month of the diary’s entries.