It reminds me of adults playing trick or treat! but in the springtime," said a woman walking up the front steps with map and guidebook in hand.

It was a Friday night. Candles burned in windows with six-over-six panes. The white flag with the PPS insignia hung from the wrought iron bannister. It designated that private home as a participant in the Providence Preservation Society's "Festival of Historic Houses" tour. The scene was a posh, narrow street in the section of town known as the East Side of Rhode Island's capital city.

"This is a good one," whispered the elderly gentlemen, also on the walking tour, who was leaving the restored 18th-century Victorian home and felt the need to critique.

Inside, the lady of the house nodded her greeting and smiled as visitors surveyed her home from top to bottom, often elbowing each other and commenting on the furnishings, unaware of the owner's presence.

There was a slight chill in the New England nighttime air and the blaze from a fireplace was the only illumination in the room other than candlelight. Wide floorboards, the color of aged honey, gleamed under oriental rugs that curved with the natural sag of the house. A mantel embellished with a Greek key frieze held a collection of the family's automobile hood ornaments. Mahogany, Hepplewhite furniture, flowered-chintz couches, starched white curtains all blended together to make a home.

The children's school pictures were tucked into a beveled-edge mirror and school papers were taped to the refrigerator in the kitchen (the only room in most of the renovated homes that has been completely modernized). An outside wall had been removed and replaced with a glass enclosure, creating a greenhouse effect for the shelves of blooming plants and hanging ferns.

"Actually, you can do anything you want to the houses inside. Sneak in a skylight, for instance, as long as you can't see it from the street or you don't change the exterior," said Liz Chase, a member of the society and a real estate broker familiar with the rules of the Historic District Commission. That's the agency controlling the boundaries and preservation guidelines of the area now containing 750 homes and public buildings restored with more than $20 million in private funds.

Twenty-five years ago the area was a slum and about to be demolished completely in the name of urban renewal. Flimsy partitions created cheap rooming houses out of the mansions once owned by prosperous China Trade entrepreneurs and wealthy turn-of-the-century industrialists. The small clapboard homes--once lived in by craftsmen--that hugged the brick-inlaid sidewalks were covered with asbestos shingles and selling for under $10,000, whenever a buyer could be found.

In the daytime, the area was acceptable because prestigious, ivy-covered Brown University was in the middle of it. But by the early evening, Benefit, Power, Sheldon, Prospect and a number of other streets--all names once associated with puritanical, Yankee Rhode Islanders--became the avenues of fortune for prostitutes, with feathers in their hats and earrings dangling from their lobes, who wiggled down streets once trod by Edgar Allen Poe and George Washington. They even sauntered right past the First Baptist Church in America, built in 1775 and still serving an active, continuing congregation.

Out of despair for the demise of Rhode Island pride, John Nicholas Brown and Antoinette F. Downing founded the Providence Preservation Society and encouraged wealthy families to buy into the area and renovate. (One owner remembers standing in a cold, empty front hall of a 15-room mansion watching rainwater run down the front hallway.)

One by one, the homes were salvaged and the legendary success in future years caused the Benefit Street area to be dubbed "The Mile of History." It has brought the solid citizen back and spurred economic and tourist development in a city only 18 miles wide with a population of 156,000 and not growing. No wonder the PPS shows off some of the homes and gardens with such pride.

This year's focus will be in an area platted during the 1790s. Clapboard homes of craftsmen and small businessmen have been chosen for the Friday Night Candlelight Tour on May 7, from 7 to 10 p.m., because of the imaginative renovation done by the owners.

Saturday, May 8, there are two tours, with a mix of modest dwellings, mansions and Colonial Revival-style homes. The daytime house and garden tour is from 10 a.m. to 4 p.m., followed by the traditional wine and cheese party for all tour participants from 4 to 5 p.m. at Hamilton House, a late 1800s, French-style, three-story stone residence adapted for use as a senior citizens center.

On the Saturday evening 7-to-10 candlelight tour, early 19th-century homes will predominate. The 33 homes on the tour are not interchangeable and are open only during the specified times.

The PPS tour is a lovely way to take a few steps back in time when neat white picket fences enclosed tulip beds in a city backyard.

It's flowering cherry tree branches shading rows of purple and yellow pansies on sidewalks that heave from winter frosts and age. It's hand-crocheted doilies on antique furniture and cast-iron stoves still used to make a good thick stew. It's standing in the middle of a study walled in bookcases with a portrait of someone's great-great-grandfather staring down at you and listening to the master of the house talk about its history and being mesmerized by his diction and aloofness.

You'd almost expect to find carriages waiting to take you from house to house, but the PPS provides free bus shuttles instead. Ticket in hand, you become a sanctioned peeping Tom on the loose. PPS volunteers stand like guardians in all the rooms, fielding questions and silently patrolling for the owners.

"Actually, because of the increase in burglaries during the year, all of us have sent our silver and anything of value out for storage," said Richard Harrington, curator for 30 years of Mrs. John Nicholas Browns' military artifacts collection.

"I rope off my living room and put plastic runners over the rugs," he added, noting that 700 people have passed through his home in one day. "My God," he huffed, "at one point they were lined up outside like Radio City Music Hall. But I open up my home for the society. The tour is good revenue for them."

Tickets sell for $15 per tour in advance, $18 on the day of the tour. The best accommodations for out-of-towners is with a package at the Biltmore Plaza hotel. Priced at $140 per person, double occupancy, the package includes two nights, continental breakfasts, Friday buffet dinner, Sunday brunch and tickets for the Friday evening and Saturday daytime tours, plus free shuttle to festival tour sites.

If you are not able to take the Historic House Tours, the PPS sponsors daily walking tours year-round (adults $2.50, children $1) and also suggests routes you can take yourself. A long lunch tour is available for $13 if you notify the PPS a week in advance. "Depending upon the availability of the owner, some private homes can be viewed, too," said Carol Hagglund of the Society, "but don't hold me to that promise."

For information or reservations, contact the Providence Preservation Society at 24 Meeting St., Providence, R.I. 02903. (401) 831-7440.AAlbanese is a free-lance writer who lives in Providence.