Beneath the generic black on white lettering of Cambridge street signs--"Parking. By Permit Only," "Tow Away Zone"--hang inviting renderings of homes, bridges and snowy streets. A closer look reveals that the bolts fastening the paintings have been turned upward in anticipation of thieves.

The contrast between the effort to give art to the city and to protect it from its citizens is a hard one to reconcile for Tom Dempsey, the man responsible for painting and hanging seventeen streetside works of art over the last two years. But then the whole notion of being a professional artist is something that Tom, who signs his work with the mysterious, yet homey signature of `Tom the Friendly Neighborhood Artist', finds troubling.

"Artwork has a monetary value, but it should have a more emotional value," he says. To make art something other than a static endeavor which is either purchased for large sums of money, or viewed on weekends by large crowds in prestigious museums, Tom has made his art a literal part of the city.

"The paintings were meant as a test for the community," he says, apologizing for his preachy tone. Of the original 17 paintings, 10 are now left. Following the first thefts, Tom returned to each painting, bolting them down as he went.

But if Tom has made this concession to the realities of urban existence, he makes few others in his effort to turn a city into a museum.

And so on the corner of DeWolfe. St. near the Weeks Bridge, as an old man in a dirty blue ski jacket pushes his belongings by in a shopping cart, Tom's view of the bridge on a sunny day hangs on a green signpost.

In another corner of the city, a loud pickup truck comes to a hault, the engine still running. From the truck's back, a large German Shepard leaps out, a thick piece of wood between his teeth. The driver checks the frontdoor of one of his client's homes and calls Dusty back to his place. In the background, almost incidentally, Tom's rendering of a quieter street in a colder season, looks on.

"I'm not trying to lay something on them," Tom says, as the truck pulls away. "I prefer the backdoor approach. The paintings are meant to say, "Welcome, Welcome." Your enjoyment is my reward. It's something as mundane and stupid as all that."

But Tom's arts project did not begin as an altruistic gesture for Tom. Anger, as much as friendliness, spurred the tall, lanky 38-year old to challenge conventional notions of cities and galleries.

With the plight of homeless Americans suddenly becoming visible in the winter of 1985, Tom became increasingly bothered by what he terms the Reagan era's celebration of salesmanship.

"You take the flimsiest idea, and fortify it with talk to turn it into saleable things. Like Reagan--he has flimsy philosophical ideas, but how he sells them is masterful," Tom says in a soft voice. He apologizes often for not being able to pin down the phrases that he wants; his words like his paintings more representational than realistic.

His first paintings, which carried the motto "Greed is not a virtue," were meant to counterbalance the obsessive drive for money which he felt had overtaken the country. "It was a gentle rebuke to all that crap," he says.

In 1985, the teacher at the Massachusetts College of Art put his first painting up, an abstract work, which he now dismisses as being fairly poor. He chose to sign it "Tom the Friendly Neighborhood Artist" because to put his real name on it would have implied that the city had approved his project. They hadn't.

"I was a renegade," he says. "If it's signed, it means it's endorsed."

Tom, a self-described victim of Harvard Real Estate (HRE) no longer lives in Cambridge. He lived in a rent controled, Harvard-owned apartment until the University sold the place to a faculty member. Since it was then owner-occupied, the rent tripled and Tom had to retreat to Brookline. Touring the streets of his urban gallery, Tom greets HRE trucks with a faint call, "Hey there, remember me?"