In the 16th century the changes in the wealth and culture of the upper social orders caused tastes in music to diverge. There was an internationalisation of courtly music in terms of both instruments, such as the lute, dulcimer and early forms of the harpsichord, and in form with the development of madrigals, pavanes and galliards. For other social orders, instruments like the pipe, tabor, bagpipe, shawm, hurdy-gurdy, and crumhorn accompanied traditional music and community dance. The fiddle, well established in England by the 1660s, was unusual in being a key element in both the art music that developed in the baroque, and in popular song and dance. By the mid-17th century, the music of the lower social orders was sufficiently alien to the aristocracy and "middling sort" for a process of rediscovery to be needed in order to understand it, along with other aspects of popular culture such as festivals, folklore and dance. This led to a number of early collections of printed material, including those published by John Playford as "The English Dancing Master" (1651), and the private collections of Samuel Pepys (1633–1703) and the Roxburghe Ballads collected by Robert Harley, 1st Earl of Oxford and Mortimer (1661–1724). In the 18th century there were increasing numbers of collections of what was now beginning to be defined as "folk" music, strongly influenced by the Romantic movement, including Thomas D'Urfey's "Wit and Mirth: or, Pills to Purge Melancholy" (1719–20) and Bishop Thomas Percy's "Reliques of Ancient English Poetry" (1765). The last of these also contained some oral material and by the end of the 18th century this was becoming increasingly common, with collections including John Ritson's, "The Bishopric Garland" (1784), which paralleled the work of figures like Robert Burns and Walter Scott in Scotland. It was in this period, too, that English folk music traveled across the Atlantic Ocean and became one of the main foundations of American traditional music. In the colonies, it mixed with styles of music brought by other immigrant groups to create a host of new genres. For instance, English ballads, combined with Irish, Scottish, and German musical traditions as well as the African banjo, became bluegrass and country music, which evolved, when combined with African-American blues, into rock and roll.