Aligning the drums Stacking and aligning column drums is another challenge. When Korres's crew separates two original drums for the first time in 2,500 years, they discover the ancients' ingenious solution. When mating two drums, the Athenians carved two pieces of cedar, one fitting inside the other like a key into a lock. These were set into holes cut in the center of each drum; when one drum was lowered onto the other, the cedar ensured proper alignment. Here, architect Cathy Paraschi displays three pairs: an original set (at left, still smelling of cedar), a modern copy (stacked at center), and a pair made out of titanium for use in today's restoration.