d of any organized
body of singers, in opera, oratorio, cantata, &c., and, in the form
"choir," of the trained body of singers of the musical portions of a
religious service in a cathedral or church. As applied to musical
compositions, a "chorus" is a composition written in parts, each to be
sung by groups of voices in a large body of singers, and differs from
"glee" (q.v.), where each part is for a single voice. The word is also
used of that part of a song repeated at the close of each verse, in
which the audience or a body of singers may join with the soloist.

In the early middle ages the name _chorus_ was given to a primitive
bagpipe without a drone. The instrument is best known by the Latin
description contained in the apocryphal letter of St Jerome, _ad
Dardanum_: "Chorus quoque simplex, pellis cum duabus cicutis aereis, et
per primam inspiratur per secundam vocem emittit." Several illuminated
MSS.[1] from the 9th to the 11th century give fanciful drawings,
accompanied by descriptions in barbarous Latin, evidently meant to
illustrate those described in the letter to Dardanus. The original MS.,
probably an illustrated transcript of this letter, which served as a
copy for the others, was apparently produced at a time when the Roman
bagpipe (_tibia utricularia_) had fallen into disuse in common with
other musical instruments, and was unknown except to the few. The Latin
description given above is correct and quite unmistakable to any one who
knows the primitive form of bagpipe; the illustrations must therefore
represent the effort of an artist to depict an unknown instrument from a
description. Virdung, Luscinius and Praetorius seem to have had access
to a MS. of the Dardanus letter now lost, and to have reproduced the
drawings without understanding them. In a MS. of the 14th century at the
British Museum,[2] containing a chronicle of the world's history to the
death of King Edward I., the chorus is mentioned and described in
similar words to those quoted above; in the margin is an elementary
sketch of a primitive bagpipe with blowpipe and chaunter with three
holes, but no drone. Bagpipes with drones abound on sculptured monuments
and in miniatures of that century. Gerbert gives illustrations of the
fanciful chorus from the Dardanus letter and of two other instruments of
later date; one of these represents a musician playing the
_Platerspiel_, the other the bagpipe known as _chevrette_, in which the
whole skin of the