MARBLEHEAD-Visitors may have noticed that two prized historical items are missing from the first floor of Abbot Hall.But Wayne Butler of the Marblehead Historical Commission has an explanation.Butler told selectmen Wednesday night the due to the sanding and refinishing of the floors in Abbot Hall the 1924 USS Marblehead Bell has been temporarily put in storage.That bell, shining as if for an admiral?s inspection, has stood in the center of the first floor hallway for years. Volunteers Steve Ware and John Philbrick helped Butler to move the bell.When the bell returns to its place of honor, it will have company n and a new pedestal.Butler said Bill Cooper and Scott Campbell are making a new stand that will hold not only the 1924 bell but the recently acquired 1893 USS Marblehead bell as well.Visitors to the selectmen?s meeting room may have noticed something missing as well.The town?s letter from the Marquis de Lafayette, who visited the town on more than one occasion, is missing from its place on the wall.The letter is being treated at the New England Document Center for changes caused by sunlight. It will be copied and the copy will be on display from now on, while the original reposes in a safe, out of harm?s way.Ultra-violet sunlight causes documents to fade. Looking around the room, Butler noted that the original deed to Marblehead is in less danger because it doesn?t receive direct sunlight. “Even so,” he said, “the cover should be put over it when it?s not being shown.”