looked, as somebody clever once said, like the box the building should have come in. The director didn't quite slaver over Maggie's hand, but he personally took us down to the laboratory level, where a String package was being assembled.
The lab looked like the world's cleanest machine shop, with concrete floors and a lot of noise. The String package was in a back room. Entry was through three sets of glass doors, and for the last two the director needed different-colored key cards.
String was the size of a console television. It was mounted on a testing gyro that allowed it to swivel freely. There was nothing tidy about it. Wires and electronics boards stuck out at all angles. There were nozzlelike protrusions here and there, and cylindrical openings where other nozzlelike protrusions would fit. A dolly full of testing equipment sat next to it, and nearby, two engineers in blue smocks argued about readouts. They stopped when we walked in.
Maggie introduced me as Mr. Lamb and told them I was cleared for all access. "What do you think?" she asked me.
I walked around the instrument package and shook my head. "Beats the shit out of me," I said.
"We could give you the Bigshot show," one of the engineers suggested. He had tape wrapped around the bridge of his glasses, which gave him a slightly crazed look. "It'd take about two minutes to rig up."
"Sure, why not?"
The testing equipment was quickly disconnected. The two engineers rolled in a dolly that carried what looked like a cartoon fishbowl, except that it bristled with short metallic rods. At the end of each rod was a glassy bubble. The engineers fitted the fishbowl around the String package like a Plexiglas jacket, and plugged in a half dozen multicolored flat cables.
"Okay," said one of the engineers. There was a keypad with a tiny digital LED panel on the side of the package. He punched a few buttons and peered at the readout, punched a few more, and nodded.
"Mr. Lamb, if you could stand right here." He pointed at a spot on the floor and I stood there. "Okay. Now look at this screen."
He turned on a monitor. It showed what looked like a head as painted by a two-year-old.
"That's your head as interpreted by high-frequency audio waves, infrared sensors, radar and laser rangers. Right now we're looking at the laser sensing. You can read it like a contour map. The brightest yellow part is your nose, then it moves through the red, green, and blue as it goes further back.
"Now here," he said, flipping on another monitor, "is a simulated three-dimensional readout of your head, and its direction, size, range, velocity, and probable identity shown down here in the corner of the screen."
Most of the numbers were meaningless unless you knew the code sequences, though under "identity" it said "head."
"We rigged it to say head," said the engineer with the crazed look.
"Now move around the room," said the other one. I moved, and the readouts changed. "It's following you," he said.
I stepped behind Maggie and looked over her head. It was still following me, and when I came out from behind her, continued to follow.
"Your personal characteristics were read into the computer, so it followed only you. We have it programmed for a single target, or it would have picked up Ms. Kahn as a second target and started a separate reading on her, while registering that you were eclipsed behind her."
"Neat," I said. "Listen, what is this audio thing, and what use can you make of audio pickups if you've got two planes on diverging courses, each at, say, Mach 2?"
"Okay," said one of the engineers, slipping into a professorial tone. "You have to understand.
Maggie and the director excused themselves after fifteen minutes of it. I stayed for another two hours looking at the machinery and talking about the software that would run the stuff. It was not my field at all, but I could see the concepts. If I started studying right away, it would only take six years to catch up with what they were