The Pastoral pipes, also referred to as the hybrid union pipes, organ pipe and union pipe, had been a bellows-blown bagpipe that served as the forerunner and ancestor of the 19th-century union pipes, which in the end evolved into the contemporary Uilleann pipes.

Bellows-blown, similar to Uilleann pipes, unlike mouth-blown Great Highland Bagpipes.
Foot joint: This enabled playing a lower leading note, expanding the range compared to earlier bagpipes.
Two-octave chromatic scale: This broader range allowed for more complex and diverse musical expression.
Simple keywork: Made them easier to play compared to some later, more elaborate bagpipes.
Their sound was generally described as softer and sweeter than other bagpipes, with a more chamber-like quality.
This made them suitable for indoor performances and classical repertoire.