Tance was walking slowly toward the gun, peering nearsightedly up at it. "Quite complex, isn't it? All those vanes and tubes. I suppose this is some sort of a telescopic sight." His gloved hand touched the end of a long tube.
Instantly the gun shifted, the barrel retracting. It swung—
"Don't move!" Dorle cried. The barrel swung past them as they stood, rigid and still. For one terrible moment it hesitated over their heads, clicking and whirring, settling into position. Then the sounds died out and the gun became silent.
Tance smiled foolishly inside his helmet. "I must have put my finger over the lens. I'll be more careful." He made his way up onto the circular slab, stepping gingerly behind the body of the gun. He disappeared from view.
"Where did he go?" Nasha said irritably. "He'll get us all killed."
"Tance, come back!" Dorle shouted. "What's the matter with you?"
"In a minute." There was a long silence. At last the archeologist appeared. "I think I've found something. Come up and I'll show you."
"What is it?"
"Dorle, you said the gun was here to keep the enemy off. I think I know why they wanted to keep the enemy off."
They were puzzled.