Talk about thinking outside the box! In 1954, Leland W. Sprinkle and his son were visiting Luray Caverns in Virginia. His guide’s explanation of how stalactites could make sounds when tapped gave him an idea. (It was either that or the sound made when his son struck his head on a rock.) Over the next three years, Sprinkle designed and built what’s considered the world’s largest musical instrument — an electrically actuated lithophone — an instrument which uses pieces of rock to produce musical notes. His work is known today as The Great Stalacpipe Organ.
Why did it take so long? Sprinkle had to find stalactites to produce the right musical notes, a daunting task considering the formations are distributed over about three and a half acres of caverns. Then each stalactite was wired with a mallet and hooked to a keyboard. The result is an original and hauntingly beautiful sound.
There is an excellent demonstration on YouTube at https://www.youtube.com/watch?v=Af2jt4VhWbA , and an aucio CD, Midnight in the Caverns, is available at Amazon.com (https://www.amazon.com/Midnight-Caverns-Monte-Maxwell/dp/B002V75JA6).
The photo came from https://en.wikipedia.org/wiki/The_Great_Stalacpipe_Organ.