Eduoard Du Puy

A half cadence is a type of cadence that ends on the dominant chord of a given tonic. Using Eduoard Du Puy's Ouverture Til Syngestykket Ungdom og Galskab (Overture to the Singspiel Youth and Folly) as an example, the half cadence at the end of this excerpt forms a E7 chord, the dominant of its home key, A major. Half cadences were often used in eighteenth century galant music to create a dramatic hault in the work and to separate section to section. 

The galant triplet (three-note division of a beat) is common rhythmic device used in eighteenth century galant music. Triplets are used in this excerpt of Edouard Du Puy's Ungdom og Galskab (Youth and Folly) to separate sections, from a duple to triple meter, as well as adding rhythmic interest in this overture.