Robert L. White, 54, who turned a chance autograph from President John F. Kennedy into an obsession and then into a makeshift museum, died Oct. 11 at Howard County General Hospital after a heart attack. He lived in Woodbine.

From the moment a young Mr. White received his Kennedy signature, he became gleefully caught up in the swell of the Camelot myth. He bought Kennedy artifacts as they became available, storing the property in his mother's Catonsville, Md., home for years. There, in her basement, he co-mingled JFK's christening ring with the president's rocking chair.

He also housed hundreds of items "once touched by" the president or his confidants. Such goods -- perhaps a coffee cup that touched the candidate's lips at a campaign stop -- might have dubious historical value to many, but they seemed to fill Mr. White with a sense of deep purpose.

Mr. White was said to have kept the largest assemblage of Kennedy memorabilia: about 25,000 pieces of correspondence and items of Camelot chattel.

His mother liked his using her basement for the collection, especially since it assured her a daily visit from her son, who wanted to check on the Kennedy wallets and passports, the reading glasses and lockets of hair.

As word spread of the curious collection, he received visitors by appointment and never charged them. He encouraged people to touch the items, and he loved nothing so much as photographing guests in a Kennedy rocking chair so they could take home a memory of their brush with history.

The collection expanded because of Mr. White's friendship with Kennedy's former personal secretary, Evelyn Lincoln. After her death in 1995, she bequeathed to Mr. White hundreds of items she had as mementos from her own Kennedy association.

Mr. White's accumulation remained a largely private affair until the mid-1990s, when he left his longtime job selling industrial cleaning supplies to start a more formal JFK museum. He hoped for public funds to help the effort, but nothing was finalized.

But he was encouraged by the millions raked in through Sotheby's 1996 auction of the estate of Jacqueline Kennedy Onassis. Mr. White decided he would sell some of his Kennedy wares and use the income for his own museum.

That drew the ire of the Kennedy family and the attention of the U.S. government, which began to probe whether the goods were federal property.

In the end, Mr. White withdrew some items from auction, including a mahogany clock that once had ticked in the Oval Office and journals from Kennedy's congressional career.

Bad feelings lingered between Mr. White and the Kennedy family. For him, the operation had not been about profit for its own sake.

Without his own official museum, he lent his collection to the Florida International Museum in St. Petersburg in 1998 and during the next few years accompanied a traveling exhibition.

Robert Louis White was a tall, tanned, outgoing baseball player in his youth. Growing up in the Baltimore suburbs, he loved talking about his friendship with Orioles pitcher Hoyt Wilhelm, a Hall of Famer who taught him to throw a knuckleball.

Baseball-card collecting led to a fascination with memorabilia in general, whether a letter from horror film actor Boris Karloff or a seltzer bottle signed by two of the Three Stooges.

His growing interest coincided with Kennedy's 1960 presidential election. He felt an instant connection to the charismatic fellow Catholic.

While his Kennedy possessions brought him the most attention, he held on to tens of thousands of other items related to the worlds of film, sports and, sometimes, infamy. He had a piece of bloody towel he claimed was used to wrap Abraham Lincoln's wounds after he had been mortally shot in 1865.

His family took his preoccupation in stride, his children in particular. They said they often were disappointed with visits to prominent museums, where the handling of objects was frowned upon.

Survivors include his wife of 29 years, Jacquelyn Slick White of Woodbine; a son, Zachary S. White of Ellicott City; a stepson, D. Christopher Slick of Eldersburg, Md.; a brother, William M. White of Catonsville; three sisters, Delores Twamley of Princeton, N.J., Dorothy Mason of Catonsville and Margaret Codella of Cranford, N.J.; and a granddaughter.

Robert L. White shows off his collection at his mother's home in 1996.