“He shuddered at the idea of digging beneath the surface. It would be stifling, hot, filthy, and dangerous. The ferrets also occasionally commandeered a heavy truck, loaded it with men and material, and drove it, bouncing along, around the outside perimeter of the camp. They believed the weight would cause any underground tunnel to collapse. Once, more than a year earlier, they'd been right. He remembered the fury on Colonel MacNamara's face when the long days and nights of hard work were so summarily crushed.”