T-139 isn’t a disease,” Houk said quickly. “It’s a nerve gas. And if I had my choice, I’d rather this was a nerve gas attack. Once gas has dissipated, the threat is over. A biological threat is considerably harder to contain.” “If it was gas,” Copperfield said, “it’ll have dissipated long ago, but there’ll be traces of it on almost everything. Condensative residue. We’ll be able to identify it in no time at all.”
