In 1989 The Deep Listening Band (Pauline Oliveros, Stuart Dempster, Panaiotis with guests Fritz Hauser and Julie Lyon Balliett) explored the sound properties of the Tarpaper Cave in Rosendale, New York. Rain Delay is from the 1990 CD Troglodyte’s Delight (¿What next?). 

Music For The Williamson Tunnels: A Collection Of The Sound Of Dripping Water 

As Brian Eno made music for environments rather than from them (Music For Airports) these CDs are best listened to within the strange damp world of the Williamson Tunnels in Liverpool. The ceilings of these caverns are thin and the sound of dripping water can frequently be heard, but not necessarily seen. It is a sound that has intrigued artists for nigh on a century and this collection brings together historical pieces alongside new compositions from artists who have expanded that first single drip:  Link