But at the first red light you take the gauze out of your pocket and unfold it for a brief peek, Eric said, and there's nothing there but a small mound of powder because your teeth have completely crumbled. These hard strong reliable structures designed for biting and gnawing, for tearing flesh. These things that last a million years in the jaws of prehistoric people, in the skulls that we dig up and study. Turned to dust in your pocket in six frigging minutes.

He called Janet and talked. He talked and listened. The smaller the talk, the better he felt. He took satisfaction in the details of her day, the matters of barely passing interest that struck him in his lonely love as items of privileged witness.

Sometimes she talked about her work, trauma duty deep in the night, and she was matter-of-fact about it, bodies flopping on the just-mopped floor of the corridor, relatives dragging in a knife victim or OD, the uncle and mother gripping the man's head and legs and a cluster of small kids at the edges, two to each arm.

She described scenes that were like paintings of the European masters, the ones who did miracles and wars.

Her strength in these matters made her beautiful to him. She was a smallish woman, they were both fairly short and Janet was slight as well, and he liked to imagine her in a scrub suit plunging a fist into someone's chest cavity and coming out with a bullet or a chicken bone. Her shyness did not conceal her eloquence of mettle and will. He saw and heard it often. She clung to him persistently to make a point.

He thought they were too damn earnest. They wanted a family and each other but were periodically beset by the complexity of the undertaking, the plans, the chances, the cities, the idea of marriage and children and jobs and how hard it is to do everything right, and they agreed and bargained and argued, they planned and fought.

He looked at Landsat photos shot from space a year or two earlier. The pictures were false-color composites that revealed signs of soil erosion, geological fracture and a hundred other events and features. They showed stress and drift and industrial ravage, billion-bit data converted into images.

He saw how remote sensors pulled hidden meanings out of the earth. How sweeps and patches of lustrous color, how computer fuchsias or rorschach pulses of unnamed shades might indicate a change in water temperature or where the dwindling grizzlies go to forage and mate. He looked at spindly barrier beaches that showed white as shanked bone. He found sizable cities pixeled into mountain folds and saw black lakes high in the ranges, kettle holes formed by glacial drift.

He could not stop looking.

The photo mosaics seemed to reveal a secondary beauty in the world, ordinarily unseen, some hallucinatory fuse of exactitude and rapture. Every thermal burst of color was a complex emotion he could not locate or name.

And he thought of the lives inside the houses embedded in the data on the street that is photographed from space.

And that is the next thing the sensors will detect, he thought. The unspoken emotions of the people in the rooms.

And then he thought inevitably of Nick.

He wanted to call his brother many times. He thought he'd like to talk to him about the work he was doing here. He'd be able to give Nick a general sense of things, let him know that the kid was doing important work but that it troubled him now and then.

One day he might find himself putting together a physics package, the explosive components of a nuclear device – true-blue bombhead country.

Matt wasn't sure he could deal with this himself. He could if he had to, and Janet would help, she'd have a clear position he could set against his doubts, but he wanted to talk to Nick. He wanted to hear his brother's voice coming down the phone line, the slightly bent stresses that carried a literal lifetime of associations.

Nick had a graveness that was European in a way. He was shaped and made. First unmade and then reimagined and strongly shaped and made again. And he was somber and self-restrained at times and not free-giving but maybe he would give the kid advice about the moral and ethical aspects of this kind of work. Mainly what Matt wanted was a show of interest. This was more important than outright counsel, a recommendation or judgment, but he wanted that too – a judgment in his brother's voice.

He didn't know what his brother might say. He might say this is the way you define yourself as a serious man, working through the hard questions and harrowing choices, and if you stick with it you'll be stronger in the end. Or he might say, Fool, what kind of mark will this make on your soul when you become a father like me? Think of the guilt of raising children in a world you've made – your talent put to such desolate use. Speaking softly now. And who knows the ticklish business of weapons better than I do, brother?

But he'd never make that last remark, would he? And Matt didn't make the call. They didn't often talk, or they talked about their mother, or they hassled each other routinely, but maybe he'd call later when he felt the urge again.

When the wind gusted out of the mountains it rebodied the dunes and if you were up out of the Pocket and sitting around at home with a beer and a snack you saw your laundry go horizontal on the backyard line, all of it, sheets, hankies, boxer shorts, pajama bottoms, like people of all sizes and shapes snapping from the pressure, letting their souls fly forth to the gypsum hills.

"But that's not the point," Eric said, "you keep mi, mi, missing the point."

It was raining in the mountains.

Eric had a fake stutter he liked to use to texture the conversation, a thing he'd developed to mock himself or his listener, although neither one of them stuttered, or maybe he was imitating some nightclub comic or simpy character on TV-it wasn't clear to Matt.

He looked out a window of Eric's bungalow. The rain was a wall of smoky shimmer that hung across the limestone bluffs. Eric sat on a sofa that was still wrapped in warehouse plastic amid a mess of scientific journals, UFO monthlies, supermarket tabloids, half a dozen Playboys and some lost food.

"Even though huge amounts of territory were affected and large numbers of people were exposed, it remains a major secret to this day."

"So secret it may not be true," Matt said.

"Do you believe it's true?"

"I believe mistakes were made."

Eric enjoyed this. His shadow smile appeared at the far end of the sprawled body. It came and went, like some inner dialogue he was conducting that ran parallel to the spoken lines, a thing of elusive drift.

"But the point is, pure and simple."

"What's the point, Eric?"

He picked up a magazine and leafed through it aimlessly, speaking in a tone that was slightly impatient but mostly, now that he was finally coming to the point, a little weary and bored.

"It was done deliberately," he said. "They knew the tests weren't safe but they went ahead anyway. They marched troops to zero point after the detonations. They sent manned aircraft through radiation clouds. They injected people with plutonium to track its course through the body, They did this deliberately, without telling people what the risks were. They exposed troops to the atomic flash and some of them were given protective eye filters and some were not. They experimented on children, infants, fetuses and mental patients. They never told the Navahos who worked in uranium mines what the dangers were. The dangers were considerable as it turned out. They zapped the testicles of prison inmates. They basically grabbed you by the balls and zapped you full of x rays. This is the story I hear. Do you believe it?"