A breath of even cooler air came flowing up into Ben’s face as he followed Robert and Jill down into the sub-basement. Blocks of gray granite had been stacked to make simple steps, twelve of them. Straight ahead at the bottom there was a small space—just enough room for the chains and pulleys that kept the door raised. He did a double take when he saw the weights—two large rusty cannonballs hung at the end of each chain. Ben tilted his head back and looked up at the hatch suspended above him. The bottom of the three wide oak planks had been sheathed with copper—the whole thing had to weigh several hundred pounds.