The glockenspiel is a percussion instrument similar in form to the xylophone, but with metal rather than wooden bars for the notes. The instrument appeared only gradually in the concert hall and opera house and is found in Handel’s oratorio Saul and elsewhere. Mozart made famous use of the glockenspiel in Die Zauberflöte (‘The Magic Flute’), where it is a magic instrument for the comic bird-catcher Papageno. It is now a recognised if sparingly used instrument in the percussion section of the modern orchestra.

Impressionism was a term at first used mockingly to describe the work of the French painter Monet and his circle; they later made use of the word themselves. It was similarly used to describe an element of vagueness and imprecision coupled with a perceived excess of attention to colour in the early music of Debussy, who did not accept the criticism or the label, although his harmonic innovations and approach to composition have points in common with the ideals of Monet.