It was like finding a Rembrandt under a paint-by-numbers canvas.

Contractor Brad Kellogg made a remarkable discovery in November while he was removing 1970s-era drywall and wainscoting from an 1840s-era church at Autrey Mill Nature Preserve and Heritage Center in Johns Creek.

Hyosub Shin/AJC (ENLARGE)

Nails believed to date to the 1800s are just some of the items discovered as workers renovate the old church at Autrey Mill.

Hyosub Shin/AJC (ENLARGE)

An 1840s church that was moved to Autrey Mill Nature Preserve and Heritage Center after it stood in the way of a bulldozer in Johns Creek has offered surprises for renovators.

Hyosub Shin/AJC (ENLARGE)

The 1840s former Methodist church at the Autrey Mill Nature Preserve and Heritage Center will host weddings and community activities after its renovation is done.

Hyosub Shin/AJC (ENLARGE)

Juan Jose of Kellogg Construction cleans an original window that's part of the tongue-and-groove walls.

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Hidden under the most recent remodeling were the original interior walls, thought to be long gone. They retained their pale yellow coat of paint.

"We knew the exterior paneling was original, but not the interior," said Cheryl Bowlin, an Autrey Mill board member. "We had no clue that anything inside had been preserved."

Autrey Mill workers probably will put a slab of clear Plexiglas over a section of the wall for display, but then will paint over the rest of it to protect it, Bowlin said. The walls feature tongue-and-groove boards and are so evenly cut and placed that the separation between them is as fine as a pencil line.

The discovery came as Autrey Mill was restoring the 160-year-old Methodist church, which used to be in the Warsaw community of Johns Creek. When the restoration is finished, Autrey Mill leaders hope to use it for weddings and as a community center. The church will hold about 80.

Churches in the rural South in the 1840s often served as a center of the community, a place for seeing friends and family and, of course, for spiritual guidance. Ministers of all denominations often rode circuits, making regular stops at churches scattered over a district. Residents would attend whatever local church happened to have a minister present.

Over the years, the old Warsaw Methodist church was modernized with the addition of air conditioning and heating. A concrete Sunday school facility was added to the back.

Until about four years ago the church rested near a cemetery on Ga. 141 just north of State Bridge Road.

The building was home to a Lutheran church for a while and served as a Boy Scout hut. It ceased to function as a place of worship in about 2000.

Saving the church was a battle.

It was on the verge of being demolished for a new strip mall. Janis Hill, who attended the old church as a child and whose 82-year-old mother, Lillian Long Dockery, is the oldest living member, fought to save it through Fulton County. Hill's family had attended the church for five generations. She was baptized there as was her mother and grandmother. Hill and her husband, John, and daughter Jodie Ritch and her husband, Quentin, attended meeting after meeting. They kept nighttime vigils at the church to ward off vandals. They made telephone calls and wrote letters. To raise money for attorneys, Hill put together and sold a cookbook of old church recipes.

"There was a lot to fight for," Hill said.

For two years, supporters of the church bogged down the proposed project. Eventually, the developer, tired of being tied down, agreed to move the church.

It sat unused at Autrey Mill while volunteers slowly labored to restore it. Work received a boost when state House Speaker Pro Tem Mark Burkhalter procured a $269,000 grant for historic preservation at the mill.

One of the first steps was to deal with honeybees that had taken up residence in three of the four corners of the church. Kellogg has rebuilt the porch, closed in a back wall, and has patched the walls, using specially milled wood to match original lumber. Using old photographs, Kellogg has constructed a wooden base for the small metal steeple that Hill's husband saved.

Volunteers pulled up a tattered red carpet and found the hardwood flooring that came from the old Duluth High School gymnasium when it was torn down around 1960. The original floor is underneath, but no one has much inclination to tear up the top layer just yet. The current floor is striped with pale lines where the pews were, and dark, worn places where people's feet were. The pews have brass plates with the names of Johns Creek families embossed on them – Medlock, Abbott, Long, Waits.

Bowlin said families used to buy pews to help raise money for the church.

The windows are tall with amber and lavender colored glass with the pebbled texture of a basketball. Bowlin said many of the panes were broken by youngsters, but they have found a glazier in Suwanee who can manufacture period replacements.

Kellogg said the construction is remarkable. The walls are from heart of pine. The frame of the structure sits in notches carved from beams and secured with wooden dowels. Kellogg said he's found corn cobs and newspapers plugging holes. Some of the beams under the floor show the rough chops of the carpenters as they hewed them to size.

Although Autrey Mill preservationists hope to make it appear much as it did, there are certain nods to the current age – building codes require a ramp, the building sits about 3 feet higher than it did, nails are round instead of square cut.

And there will be one central door instead of the original two – one for men and one for women.

"We want to rent it out, and we thought brides would want to use one door," Bowlin said, almost apologetically.

Hill said she hopes visitors will learn to appreciate the past. And she hopes they appreciate how central the church was to the community.

"Church was it," she said. "You had revival and you had church. That was our social life."

The building should be finished sometime in May.