A Dictionary of Music and Musicians/Number
NUMBER. The several pieces or sections of operas, oratorios, or other long works, are numbered for convenience of reference, etc. This is sometimes very arbitrarily done even by so methodical a person as Mendelssohn. (Compare e.g. in Elijah, Nos. 40 and 41.) The overture is never counted, but 'No. 1' is the first piece after it. See also Opus-number.
[ G. ]