You know a piece of property is doomed when people start talking about turning it into a prison. That's one of developer Jackie Welch's ideas for the Mall of Memphis. Welch has no financial interest in the property, and his suggestion came in the midst of some wide ranging musings about the general state of Memphis and Shelby County. But the owner of Welch Realty does know a little about real estate and Memphis demographics, having sold businesses and building sites along Highway 51 in Whitehaven, Winchester in Hickory Hill, and Germantown Road in Cordova as the fortunes of those areas rose and/or fell. The sprawling Mall of Memphis on the south leg of Interstate 240 has lost its anchors and scores of other tenants as retailers and customers moved east, first to Hickory Ridge Mall and then to Wolfchase Galleria. The Raleigh Springs Mall appears headed for a similar fate. Last week, Dillard's announced that it will join Goldsmith's and J C Penney in leaving the 32-year-old mall. Customers and retailers have moved south and east to DeSoto County and the Wolfchase Galleria. Attempting to recapture some of that via annexation, Memphis has stretched its boundaries out Highway 64 nearly to Fayette County. Our disposable city encompasses more than 300 square miles. For now, the most seriously sick patient is the Mall of Memphis, whose vast empty parking lots along Nonconnah Creek are in plain view of thousands of motorists passing through Memphis every day. "They ought to turn those old department stores into schools and save some money," Welch said, noting the general sense of alarm about county debt tied to new school construction. "Or they could put in a minimum-security prison." No cracks, please, about them being one and the same. These suggestions are likely to get about as far as Welch's earlier proposal to sell off a strip of Shelby Farms along Germantown Road or former Shelby County mayor Jim Rout's joking observation that Midtown's old Sears Building would make a swell prison. But the two malls on life supportmay well join the Sears Building on the perennially vacant list if somebody doesn't come up with a better idea than the Community Redevelopment Act subsidies that were proposed and then aborted by the city a few years ago. Welch, who sold nine school sites serving his subdivisions to the county board of education, said he's out of the school business and focusing on a new bank he has started called First Souce which will open in April in Germantown. "We're not going to be the leaders in the residential market for the next few years like we were for the last 10 years," he said.