While war veterans solicited donations for poppies on Loop street corners the Thursday before Memorial Day, another group was offering something less traditional. As throngs of workers with briefcases and gym bags hurried home from work, 14 solitary figures scattered up and down LaSalle Street between the Board of Trade and the Chicago River carried small digital recorders playing the sound of a heartbeat sampled off the Internet. The speakers were hidden under their clothes, close to their hearts, and from 5:00 to 5:32 PM the microphones they held to their chests amplified the sound through ten-watt battery-powered Radio Shack megaphones. These slightly mysterious citizens were participants in 32 Minutes on LaSalle, composed by performance artist Mathew Wilson and sponsored by Columbia College’s Hokin Center as part of its annual May fest.

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The performers were undemonstrative; they moved with the flow, creating fleeting eddies of embarrassment. People seemed puzzled. A few were perturbed, while more were curious but reluctant to ask what was going on or what it meant. Since Wilson stages his elusive performances in public spaces without permits or press releases, none of the passersby knew in advance what they were encountering. Wilson will often notify a critic or a reporter or two, but he’d rather have his artwork go unreviewed than risk having the presence of the media tip off potential viewers that a performance is in progress.

One participant was Wilson’s wife, Gosia, who stood with a stroller containing their three-and-a-half-year-old daughter. “People just looked at me strangely,” she said afterward. “I can’t describe the look. It was like, ‘That poor baby, what is that mother doing?’”

As Wilson’s piece ended, an impromptu performance unfolded from behind a window at the Federal Express office at 203 N. LaSalle. As an officer ticketed an illegally parked truck outside, the driver slapped his outstretched palms on the window and pantomimed a face of comic panic. But the officer never saw the show at his back.