"I'll go," Katrina offers. "We can go, too, the three of us. We need a good chance to get out," Rose says, gesturing to her sisters.<br/><br/>As he began work on the detection device, he'd discover, fairly quickly, that it would need a lot of power to detect the energy sources, and that it wouldn't have much range. The best he could get would be less than a half-mile, and that would simply inform the user that something was on the detection, not what it was. Only at a range of less than a hundred feet could it give an accurate idea of where the items truly was, getting more and more accurate, the closer it got.