Bag-Pipe (Celt. piob-mala, ullan-piob, cuislean, cuislin; Fr. cornemuse, chalemie, musette, sourdeline, chevrette, loure; Ger. Sackpfeife, Dudelsack; M. H. Ger. Suegdbalch; Ital. cornamusa, piva, sampogna, surdelina; Gr. ἄσκαυλος (?); Lat. ascaulus (?), tibia utricularis, utricularium; med. Lat. chorus), a complex reed instrument of great antiquity. The bag-pipe forms the link between the syrinx (q.v.) and the primitive organ, by furnishing the principle of the reservoir for the wind-supply, combined with a simple method of regulating the sound-producing pressure by means of the arm of the performer. The bag-pipes consists of an air-tight leather bag having three to five apertures, each of which contains a fixed stock or short tube. The stocks act as sockets for the reception of the pipes, and as air-chambers for the accommodation and protection of the reeds. The pipes are of three kinds: (1) a simple valved insufflation tube or "blow-pipe," by means of which the performer fills the bag reservoir; (2) the "chaunter" (chanter) or the melody-pipe, having according to the variety of the bag-pipe a conical or a cylindrical bore, lateral holes, and in some cases keys and a bell; the "chaunter" is invariably made to speak by means of a double-reed; (3) the "drones," jointed pipes with cylindrical bore, generally terminating in a bell, but having no lateral holes and being capable, therefore, of producing but one fixed note.
The main characteristic of the bag-pipe is the drone ground bass which sounds without intermission. Each drone is fitted with a beating-reed resembling the primitive "squeaker" known to all country lads; it is prepared by making a cut partly across a piece of cane or reed, near the open end, and splitting back from this towards a joint or knot, thus raising a tongue or flap. The beating-reed is then fixed in a socket of the drone, which fits into the stock. The sound is produced by the stream of air forced from the bag into the drone-pipe by the pressure of the performer's arm, causing the tongue of reed to vibrate over the aperture, thus setting the whole column of air in vibration. The drone-pipe, like all cylindrical tubes with reed mouthpieces, has the acoustic properties of the closed pipe and produces the note of a pipe twice its length. The drones are tuned by means of sliding-joints.
The blow-pipe and the chaunter occupy positions at opposite extremities of the bag, which rests under the arm of the performer while the drones point over his shoulder. These are the main features in the construction of the bag-pipe, whose numerous varieties fall into two classes according to the method of inflating the bag: (1) by means of the blow-pipe described above; (2) by means of a small bellows connected by a valved feed-pipe with the bag and worked by the other arm or elbow to which it is attached by a ribbon or strap.
Class I. comprises: (a) the Highland bag-pipe; (b) the old Irish bag-pipe; (c) the cornemuse; (d) the bignou or biniou (Breton bag-pipe); (e) the Calabrian bag-pipe; (f) the ascaulus of the Greeks and Romans; (g) the tibia utricularis; (h) the chorus. To Class II. belong: (a) the musette; (b) the Northumbrian or border bag-pipe; (c) the Lowland bag-pipe; (d) the union pipes of Ireland; (e) the surdelina of Naples.
1. The Highland Bag-pipe. - The construction of the Highland pipes is practically that given above. The chaunter consists of a conical wooden tube terminating in a bell and measuring from 14 to 16 in. including the reed. There are seven holes in front and one at the back for the thumb of the left hand, which fingers the upper holes while the right thumb merely supports the instrument. The holes are stopped by the under part of the joints of the fingers. There is in addition a double hole near the bell, which is never covered, and merely serves to regulate the pitch. As the double reed is not manipulated by the lips of the performer, only nine notes are obtained from the chaunter, as shown: - 
The notes do not form any known diatonic scale, for in addition to the C and F being too sharp, the notes are not strictly in tune with each other. Donald MacDonald, in his treatise on the bag-pipe states that "the piper is to pay no attention to the flats and sharps marked on the clef, as they are not used in pipe music; yet the pipe imitates several different keys which are real, but ideal on the bag-pipe, as the music cannot be transposed for it into any other key than that in which it is first played or marked." Mr Glen, the great dealer in bag-pipes, gave it as his opinion "that if the chaunter were to be made perfect in any one scale, it would not go well with the drones. Also, there would not be nearly so much music produced (if you take into consideration that it has only nine invariable notes) as at present it adapts itself to the keys of A maj., D maj., B min., G maj., E min. and A min. Of course we do not mean that it has all the intervals necessary to form scales in all those keys, but that we find it playing tunes that are in one or other of them." Mr Ellis considers that the natural scale of the chaunter of the bag-pipe corresponds most nearly with the Arab scale of Zalzal, a celebrated lutist who died c.
The three drones are usually tuned to A, the two smallest one octave below the A of the chaunter, and the largest two octaves below. The three principal methods of tuning the drones are shown as follows: - 
The excessive use of ornamental notes on the Highland bag-pipe has arisen from a technical peculiarity of the instrument, which makes a repetition of the same note difficult without the interpolation of what is known among pipers as "cuts" or "warblers," i.e. grace notes fingered with great rapidity (see below for an example). These warblers, which consist not only of single notes but of groups of from three to seven notes, not consecutive but in leaps, assist in relieving the constant discord with the drone bass. Skilful pipers have been known to introduce warblers of as many as eleven notes between two beats in a bar.
The use of musical notation for the Highland pipe tunes is a recent innovation; the pipers used verbal equivalents for the notes; for instance, the piobaireachd Coghiegh nha Shie, "War of peace," which opens as shown here, was taken down by Capt. Niel MacLeod from the piper John McCrummen of Skye as verbally taught to apprentices as follows: -
"Hodroho, hodroho, haninin, hiechin,
Hodroha, hodroho, hodroho, hachin,
Hiodroho, hodroho, haninin, hiechin," etc.
The conclusion of the tune is thus expressed:
"Hiundratatateriri, hiendatatateriri, hiundratatateriri, hiundratatateriri."
Written down this seems a mere unintelligible jumble, but could we hear it, as sounded by the pipers, with due regard for the rhythmical value of notes, it would be a very different matter. Alexander Campbell relates that a melody had to be taken down or translated "from the syllabic jargon of illiterate pipers into musical characters, which, when correctly done, he found to his astonishment to coincide exactly with musical notation."
Fig. 1. - (1) Cornemuse. (2) Irish bag-pipe. (3) Musette. (4) Highland bag-pipe, A.D. 1409. (5) Border bag-pipe.
(From Capt. C. R. Day's Descriptive Catalogue of Musical Instruments exhibited at the Royal Military Exhibition, by permission of Eyre & Spottiswoode.)
A Highland bag-pipe of the 15th century, dated MCCCCIX., in the possession of Messrs J. & R. Glen of Edinburgh, was exhibited at the Royal Military Exhibition in London in 1890 (see fig. 1 (4)). There were two drones, inserted in a single stock in the form of a wide-spread fork, and tuned to A in unison with the lowest note of the chaunter, which had seven finger-holes in front and a thumb-hole at the back.