"Mites," he said, "or so they say down at the Flea Circus anyway." He 
picked up one of the black things taken from the mask and flicked it with a 
fingertip. A cineritious cloud swirled out of it, like a drop of ink in a glass 
of water, and hung swirling in the air, neither rising nor falling. Sparkles of 
light flashed in the midst of it like fairy dust. "See, there's mites around, 
all the time. They use the sparkles to talk to each other," Harv explained. 
"They're in the air, in food and water, everywhere. And there's rules that 
these mites are supposed to follow, and those rules are called protocols. And 
there's a protocol from way back that says they're supposed to be good for your 
lungs. They're supposed to break down into safe pieces if you
breathe one inside of you." Harv paused at this point, theatrically, to summon 
forth one more ebon loogie, which Nell guessed must be swimming with safe mite 
bits. "But there are people who break those rules sometimes. Who don't follow 
the protocols. And I guess if there's too many mites in the air all breaking 
down inside your lungs, millions—well maybe those safe pieces aren't so 
safe if there's millions. But anyways, the guys at the Flea Circus say that 
sometimes the mites go to war with each other. Like maybe someone in Shanghai 
makes a mite that doesn't follow the protocol, and gets his matter compiler to 
making a whole lot of them, and sends them all across the water to New Atlantis 
Clave to snoop on the Vickys, or even maybe to do them harm. Then some 
Vicky—one of their Protocol Enforcement guys—makes a mite to go 
out and find that mite and kill it, and they get into a war. That's what's 
happening today, Nell. Mites fighting other mites. This dust—we call it 
toner—is actually the dead bodies of all those mites."