When Joe McGill spreads his sleeping bag on the floor of a slave cabin, he knows that spending the night there will conjure the specter of slavery.

"If I were a firm believer in ghosts and spirits and things of that nature, I don't think I could do this," said McGill, a preservationist who is working to preserve buildings that are part of a past that many prefer to forget....

McGill, a program officer with the National Trust for Historic Preservation, will spend Saturday night in a cabin at Hobcaw Barony near the coastal community of Georgetown....