Balinese irrigation bamboo produces a natural percussive soundscape from many mills.

Evidence

In Bali there is an ingenious irrigation system in which large pieces of bamboo on hinges fill up with water from a stream then flip over, spilling water into the rice fields. As each tips back it produces a hollow tapping sound and one may hear amid the continuous bubbling of water a delicate and irregular recital of taps from fifty or more of these little water mills in operation at once. — Schafer, Murray R, The Soundscape- Our Sonic Environment…, 840

Categorization

• XREF: Connects to Schafer’s theme of found natural music elsewhere in the book, and to field recording of agricultural acoustics. — connects to: Tuning the lengths of irrigation bamboo would produce musical melody. — Schafer, Murray R, The Soundscape- Our Sonic Environment…, 840
• corroborated: 2 independent passages support this claim — Schafer, Murray R, The Soundscape- Our Sonic Environment…, 840