It suddenly hit me, what she was saying. "What?" I said, sitting up in bed. "Are you kidding?" If it was true, it was an extraordinary development, a genuine technological breakthrough, and it meant"It's true," Julia said quietly. "We're manufacturing in Nevada." She smiled, enjoying my astonishment.

Onscreen, Julia was saying, "I have one of our Xymos cameras under the electron microscope, here"-she pointed to the screen-"so you can see it in comparison to the red blood cell alongside it."

The image changed to black-and-white. I saw a fine probe push what looked like a tiny squid into position on a titanium field. It was a bullet-nosed lump with streaming filaments at the rear. It was a tenth of the size of the red blood cell, which in the vacuum of the scanning electron microscope was a wrinkled oval, like a gray raisin.

"Our camera is one ten-billionth of an inch in length. As you see, it is shaped like a squid," Julia said. "Imaging takes place in the nose. Microtubules in the tail provide stabilization, like the tail of a kite. But they can also lash actively, and provide locomotion. Jerry, if we can turn the camera to see the nose… Okay, there. Thank you. Now, from the front, you see that indentation in the center? That is the miniature gallium arsenide photon detector, acting as a retina, and the surrounding banded area-sort of like a radial tire-is bioluminescent, and lights the area ahead. Within the nose itself you may be able to just make out a rather complex series of twisted molecules. That is our patented ATP cascade. You can think of it as a primitive brain, which controls the behavior of the camera-very limited behavior, true, but enough for our purposes."

I heard a hiss of static, and a cough. The screen image opened a small window in the corner, and now showed Fritz Leidermeyer, in Germany. The investor shifted his enormous bulk. "I'm sorry, Ms. Forman. Tell me please where is the lens?"

"There is no lens."

"How can you have a camera with no lens?"

"I'll explain that as we go," she said.

Watching, I said, "It must be a camera obscura."

"Right," she said, nodding.

Camera obscura-Latin for "dark room"-was the oldest imaging device known. The Romans had found that if you made a small hole in the wall of a dark room, an upside-down image of the exterior appeared on the opposite wall. That was because light coming through any small aperture was focused, as if by a lens. It was the same principle as a kid's pinhole camera. It was why ever since Roman times, image-recording devices were called cameras. But in this case"What makes the aperture?" I said. "Is there a pinhole?"

"I thought you knew," she said. "You're responsible for that part."

"Me?"

"Yes. Xymos licensed some agent-based algorithms that your team wrote."

"No, I didn't know. Which algorithms?"

"To control a particle network."

"Your cameras are networked? All those little cameras communicate with each other?"

"Yes," she said. "They're a swarm, actually." She was still smiling, amused by my reactions.

"A swarm." I was thinking it over, trying to understand what she was telling me. Certainly my team had written a number of programs to control swarms of agents. Those programs were modeled on behavior of bees. The programs had many useful characteristics. Because swarms were composed of many agents, the swarm could respond to the environment in a robust way. Faced with new and unexpected conditions, the swarm programs didn't crash; they just sort of flowed around the obstacles, and kept going.

But our programs worked by creating virtual agents inside the computer. Julia had created real agents in the real world. At first I didn't see how our programs could be adapted to what she was doing.

"We use them for structure," she said. "The program makes the swarm structure." Of course. It was obvious that a single molecular camera was inadequate to register any sort of image. Therefore, the image must be a composite of millions of cameras, operating simultaneously. But the cameras would also have to be arranged in space in some orderly structure, probably a sphere. That was where the programming came in. But that in turn meant that Xymos must be generating the equivalent of"You're making an eye."

"Kind of. Yes."

"But where's the light source?"

"The bioluminescent perimeter."

"That's not enough light."

"It is. Watch."

Meanwhile, the onscreen Julia was turning smoothly, pointing to the intravenous line behind her. She lifted a syringe out of a nearby ice bucket. The barrel appeared to be filled with water. "This syringe," she said, "contains approximately twenty million cameras in isotonic saline suspension. At the moment they exist as particles. But once they are injected into the bloodstream, their temperature will increase, and they will soon flock together, and form a meta-shape. Just like a flock of birds forms a V-shape."

"What kind of a shape?" one of the VCs asked.

"A sphere," she said. "With a small opening at one end. You might think of it as the equivalent of a blastula in embryology. But in effect the particles form an eye. And the image from that eye will be a composite of millions of photon detectors. Just as the human eye creates an image from its rods and cone cells."

She turned to a monitor that showed an animation loop, repeated over and over again. The cameras entered the bloodstream as an untidy, disorganized mass, a kind of buzzing cloud within the blood. Immediately the blood flow flattened the cloud into an elongated streak. But within seconds, the streak began to coalesce into a spherical shape. That shape became more defined, until eventually it appeared almost solid.

"If this reminds you of an actual eye, there's a reason. Here at Xymos we are explicitly imitating organic morphology," Julia said. "Because we are designing with organic molecules, we are aware that courtesy of millions of years of evolution, the world around us has a stockpile of molecular arrangements that work. So we use them."

"You don't want to reinvent the wheel?" someone said.

"Exactly. Or the eyeball."

She gave a signal, and the flat antenna was lowered until it was just inches above the waiting subject.

"This antenna will power the camera, and pick up the transmitted image," she said. "The image can of course be digitally stored, intensified, manipulated, or anything else that you might do with digital data. Now, if there are no other questions, we can begin." She fitted the syringe with a needle, and stuck it into a rubber stopper in the IV line.

"Mark time."

"Zero point zero."

"Here we go."

She pushed the plunger down quickly. "As you see, I'm doing it fast," she said. "There's nothing delicate about our procedure. You can't hurt anything. If the microturbulence generated by the flow through the needle rips the tubules from a few thousand cameras, it doesn't matter. We have millions more. Plenty to do the job." She withdrew the needle. "Okay? Generally we have to wait about ten seconds for the shape to form, and then we should begin getting an image… Ah, looks like something is coming now… And here it is." The scene showed the camera moving forward at considerable speed through what looked like an asteroid field. Except the asteroids were red cells, bouncy purplish bags moving in a clear, slightly yellowish liquid. An occasional much larger white cell shot forward, filled the screen for a moment, then was gone. What I was seeing looked more like a video game than a medical image.

"Julia," I said, "this is pretty amazing."

Beside me, Julia snuggled closer and smiled. "I thought you might be impressed." Onscreen, Julia was saying, "We've entered a vein, so the red cells are not oxygenated. Right now our camera is moving toward the heart. You'll see the vessels enlarging as we move up the venous system… Yes, now we are approaching the heart… You can see the pulsations in the bloodstream that result from the ventricular contractions…" It was true, I could see the camera pause, then move forward, then pause. She had an audio feed of the beating heart. On the table, the subject lay motionless, with the flat antenna just over his body.