The sun pounds down on Manhattan, sending some tourists into air-conditioned restaurants and museums; others are giving vendors fistfuls of cash for bottled water and hats.
But despite the heat, a small group of out-of-towners forms a circle on the edge of Washington Square Park and huddles over a manhole cover, cameras clicking. They "ooh" and "ahh" softly, wiping beads of sweat from their faces.
At the front of the pack stands Diana Stuart, a slight but feisty woman who knows the streets of New York backward and forward. Armed with laminated maps, a book, and loose-leaf pages of highlighted notes, the self-described "Manhole Cover Lady" tries to steer the group away from the park, promising that the cover that has caught their attention is the least of what awaits. There is a treasure trove, she insists, of old iron artwork that lies at the feet of unwitting passersby.
True, Sinatra never sang about manhole covers. But that doesn't mean they shouldn't make the cut on New York City's long list of attractions, Ms. Stuart repeats throughout the tour. The "exhibit" is, after all, free and open round the clock, as it has been since the late 1800s.
As Stuart winds the group through the quiet back streets of the West Village, her favorite manhole-cover haunt, she is quick to point out the ones that hark back to the days when "they executed these designs lovingly." When she stops to point out a particularly small and ornate sidewalk cover, one of her favorites, she shakes her head.
"They cared about design then," she says wistfully, pointing out the swirly intricacies that symbolize a bygone era.
Timothy Etinger, a participant in the tour, has been a manhole- cover enthusiast since he first discovered the iron artwork of the streets years ago. He has photographed them ever since, and he and Stuart make a quirky duo, sharing an enthusiasm for what they lament is a dying art.
At one point Mr. Etinger stoops down, camera in hand, to point out with sudden interest a newer model, a simple zigzag design. Stuart's response comes quickly, her tone hovering somewhere between diplomatic and disapproving: "This doesn't have the finesse and the class and the style of the 19th-century ones," she says.
Stuart tells the group that, years ago, foundries such as Jacob Mark and Cornell Ironworks made covers with varying patterns, from tick-tack-toe motifs to curlicues. The newer, mass-produced ones don't even compare. But with few records of the former foundries, a replaced manhole cover is a piece of history lost forever.
Which is why Stuart leads not only tours but a cause. She wants the city to landmark the centennial-aged art, which risks being paved over or replaced by today's simpler mass-produced versions. Cities such as Los Angeles and Sacramento, Calif., have landmarked their much-younger manhole covers, she argues. But New York, with an estimated 600,000 manhole covers (Stuart thinks the number is much higher), has made no such move.
Stuart never intended to become the city's grande dame of in-street art. But 10 years ago, she recalls, "I looked down and saw a stunning manhole cover, then about 30 to 40 in that one day alone, so I knew there was more to this subject than meets the eye."
What there are less and less of, however, are the intricate iron artifacts that aroused her interest a decade ago. They have been disappearing, quietly but steadily, in recent years. Stuart points solemnly to a circle in the sidewalk a few shades lighter than the concrete. A circle the size of a manhole cover.
Pulling out her recently published book, "Designs Underfoot: The Art of Manhole Covers in New York City," she flips to a photo of the manhole cover that graced the ground before being covered by pavement. "This would have been lost to history [if it hadn't been documented]," she says.
Stuart, a longtime history lover, has photographed more than a thousand manhole covers and documented more than 400 of them in her book. "Don't touch my manhole covers," she loves to joke, but her eyes darken. "This is history, right here at our feet."