"D-D-Don't Touch!" shouted the father of 6-year-old Eric Nichol as the boy curiously picked up a fragile $35 slide projector yesterday at an antique show touted as the "granddaddy of them all" on the East Coast.

Eric, his parents and thousands of other antique enthusiasts reveled in a cornucopia of antiquity yesterday as they strolled through an old tobacco barn located just outside Upper Marlboro.

The show, which included thousands and thousands of items ranging from brass beds and gleaming cut crystal to pre-Columbian statues and old oak furniture, is sponsored by St. Thomas' parish in southern Prince George's County.

Expected to net between $25,000 and $30,000 from the $2 admission price, the Tobacco Barn Antique Show has become a competitive showplace for antique dealers on the East Coast, according to a show spokesman. He said there are at least 1,100 retailers who are currently on the waiting list for floor-space in the old tobacco barn.

The show is in its 18th year and interest continues to swell, according to a number of travelling antique dealers.

The dealers are a curious lot. Many of them are over the age of 65, and are using their retirement to get the best price for items they have bought along their journey from one show to the next. "Instead of working in a store all day, we drive a truck," one dealer said.

The antique dealers peer over their displays and smile at curious customers who more often then not ask "What's that?"

The slide projector that curious 6-year-old Eric tried picked up used a kerosene lamp to illuminate handpainted slides. The lamp, according to its dealer, was used between the mid and late 1800s.

There was also a solid teak handcarved Chinese curio cabinet that sells for approximately $2,500. There was a Totanac burial figure of a priest from Vera Cruz, Mexico, that sells for $4,500 and there was a desk that is called the king of desks that sells for $10,500.

The king of desks, a Wooten Desk has several signs posted that said: "Don't Touch." A man who looked like Archie Bunker and chewed on a cigar rummaged through the desk despite the signs. His wife kept saying: "Daa..vid stop!"

Many of the spectators who wandered across the acre of floor space was impressed with both the items and their prices.

Elizabeth McClain of Arlington looked at an old oak dresser that was made back in 1800 and sold for $1,800 and said: "I love it but it just costs too much . . . where would I put it?"

The antique show will continue today. It will be open 11 a.m. to 6 p.m. CAPTION: Picture, Jackie Walden helps Robert Warren of Alexandria carry a chest Warren bought for $22 as a toy box for his son, By Charles Del Vecchio - The Washington Post