Chelsea, Nocturne in Blue and Silver. A nocturne is usually a musical composition that is inspired by, or evocative of, the night.
   Historically, nocturne is a very old term applied to night Offices and, since the Middle Ages, to divisions in the canonical hour of Matins. The name nocturne was first applied to pieces in the 18th century, when it indicated an ensemble piece in several movements, normally played for an evening party and then laid aside.
   Sometimes it carried the Italian equivalent, notturno, such as Wolfgang Amadeus Mozart's Notturno in D, K.286, written for four lightly echoing separated ensembles of paired horns with strings, and his Serenata Notturna, K. 239. At this time, the piece was not necessarily evocative of the night, but might merely be intended for performance at night, much like a serenade.
   The chief difference between the serenade and the notturno was the time of the evening at which they would typically be performed: the former around 9:00pm, the latter closer to 11:00 pm. In its more familiar form as a single-movement character piece usually written for solo piano, the nocturne was cultivated primarily in the 19th century. The first nocturnes to be written under the specific title were by the Irish composer John Field, generally viewed as the father of the Romantic nocturne that characteristically features a cantabile melody over an arpeggiated, even guitar-like accompaniment.
   However,
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