SILVER SPRING (AP).- The bullet that killed Abraham Lincoln is mounted under glass, like a diamond in a snow globe, in its new home at the National Museum of Health and Medicine. The lead ball and several skull fragments from the 16th president are in a tall, antique case overlooking a Civil War exhibit in a museum gallery in Silver Spring, just off the Capital Beltway. The military museum, known for its collection of morbid oddities, moved in September from the former Walter Reed Army Medical Center in Washington. At Walter Reed, visitors had to pass through a security gate and find the museum on the campus, where parking could be a problem. The new building stands outside the gates of Fort Detrick’s Forest Glen Annex. Visitors can just drive up, walk in and come face-to-face with a perpetually grinning skeleton directing them to an exhibit on the human body. There, one can see a hairball from the stomach of