Slide (musical ornament)

[2] In The Interpretation of Early Music, Robert Donington surveys many treatises to ascertain the history of the slide.

[1] Christopher Simpson described the figure in his Division Violist: "Sometimes a note is graced by sliding to it from the third below, called an 'elevation', now something obsolete.

Henry Purcell (1696), Jacques Champion de Chambonnières (1670) and Jean-Henri d'Anglebert (1689) use the French word coulé.

[2] Carl Philipp Emanuel Bach, in his Versuch über die wahre Art das Clavier zu spielen (1753), described the slide in two ways: 1) a two-note ascending prefix to a note; and 2) a three-note prefix similar to a turn.

[6] Bach felt that the use of the slide was determined by the character of the music, favoring "highly expressive movements.

Halting and subdued in nature, its performance should be highly expressive, and freed from slavish dependence on note values.

[7] ... To the passing appoggiature belong also those improvised ornamentations which I will call übersteigende and untersteigende Zwischen-Schläge [rising and falling intermediate gracenotes].

Bach, but quotes Agricola (in Tosi's Anleitung zur Singkunst, p. 88) that a slide could fill out a melodic gap whose final note occurs on a weak beat.