If you're wondering about the dozens of strings stretching across Third Street from Cowles Commons to the Des Moines Civic Center, it's not a massive spiderweb created to snag monster-sized insects.
It's a giant string instrument dubbed the Sonic Butterfly. The working instrument under construction is for free performances starting Thursday.
"Some of the strings are going to be as long as 200 feet," said Andrea Brook, the creator of the musical contraption adorning downtown Des Moines. "If you’ve ever experienced a Tibetan singing bowl — Tibetan singing bowls are made of brass — my strings are also made of brass.”
Also like a Tibetan singing bowl, Brook's creation may be beautiful to behold, but its main purpose is musical.