As a fifth-generation locksmith in this tough town, John Henssler figured he had heard it all.
Then a stranger walked into his family's century-old shop and offered to repaint its faded, two-story business sign _ for free.
"I thought he was pulling my leg,'' Henssler said.
But Robert Blackson was serious. The Temple University arts administrator, who passed the sign daily on his way to work, had been captivated by the ethereal lettering on the exterior wall: "Est. 1898, H. Henssler, Expert Locksmith. Any Lock, Any Key.''
Their conversation last summer led not only to a fresh coat of paint for the locksmith's sign _ the first in decades _ but also to a fledgling effort to revive other fading advertisements around Philadelphia.
Also called "ghost signs,'' these vanishing ads have become a subject of fascination in urban landscapes large and small, from New York City to York, Pa. Aficionados curate photo blogs, post pictures on Instagram and tag online maps with their locations, almost like a public scavenger hunt.
Ghost signs are generally defined as painted signage, at least 50 years old, on an outside wall that publicizes a defunct business or product, according to Lawrence O'Toole, author of "Fading Ads of Philadelphia.'' But some mark establishments that are still open.
Henssler's ad in north Philadelphia is the first ghost sign resurrected by a new partnership between Temple's Tyler School of Art and the city's Mural Arts Program. Blackson, who is leading the effort, sees the program as a way to renew small businesses and, possibly, entire neighborhoods.
"It could be a great way to boost civic pride,'' Blackson said. "I think there's loads of potential to make it a project that's not about just paint and brushes.''
The intrigue of ghost signs is multifaceted, stemming from the intersection of art, history and commerce. Some fans are captivated by the fonts and graphics, representing the nearly lost tradition of sign painting; others appreciate the ads as history writ large, telling stories about how things used to be, the industries that once powered a neighborhood or the provenance of a building.
Philadelphia has no shortage of ghost signs, left over from its two centuries as an industrial and manufacturing powerhouse. Some have been reincarnated in surprising ways.
A brick row house in the heart of downtown has two ghost signs on its side wall: ``T.J. Cobourn, Groce(r),'' with the last letter missing, and another that says ``Camac Food Market.'' Now, the building houses an Italian restaurant called Mercato _ the Italian word for ``market.''
And the former Wilbur Chocolate Co. complex in the Old City neighborhood became The Chocolate Works apartment building. The faded word ``Wilbur's'' is still visible in white on the building's side, harkening back to a time when the area was known as Confectioners Row.
Frank Jump, who has chronicled New York's vanishing ads on a photo blog and in a book, prefers for the art to be left alone.
"Once you alter the sign by either trying to restore it or painting over it, you're obliterating the original work,'' Jump said.
But Blackson noted that in Henssler's case, the sign isn't just about the art _ it's about making a living. Henssler is struggling to carry on the family tradition alluded to on his business cards: "We changed your great-grandmothers' locks.''
"I think if John was no longer in business, then maybe it should just go the way of the weather,'' Blackson said of the sign. "I want to make it clear he's still open for business.''
Over the past few months, two Tyler students and Mural Arts staff artist Nathaniel Lee have worked from scaffolds erected outside the shop, located on the bottom floor of the row house in which Henssler's father was born.
As Lee recently put on some finishing touches, he said it had been rewarding and challenging to recapture the colors, images and intention of the original artist.
Some of the areas (of the sign) were completely lost and we had to look for clues,'' he said, noting they got a little help from old photos.
Lee added that their work generated nearly all positive comments from passers-by, except for one man who said he preferred it the old way. Lee's response? Wait 10 or 15 years _ it will start to look weathered.
The Mural Arts Program plans to fund the repainting of four to six more fading ads starting this summer, working with Blackson to identify small-business owners who'd like to spruce up their signage. The program's executive director, Jane Golden, called it a way of ``honoring the past while thinking about the future.''
Henssler had wanted to repaint his flaking wall ad for years, but said he didn't have the time or money.
"People don't think you're here when they see that,'' Henssler said of the ghost sign. "Now a lot more people come in.''