'What's that?'
'It's something that happens when a human body is exposed to high levels of fear or stress. Your pulse increases but your blood pressure drops.
Physically, your son is in good shape, all things considered. He has no infections or wounds. No physical damage, other than the slight dehydration. It's really quite remarkable, Mr. Thurmond. Things could have been a lot worse. Be thankful that you got to him when you did. How long was he alone?'
'A week.'
The doctor's hushed tones became a whisper.
'I don't imagine his hair was turning that color when you last saw him either.'
'No.' Jim's voice cracked.
Stern placed a hand on Jim's good shoulder and squeezed. 'Well, he's a resilient young man, much like his father. Frankly, I'm amazed. The Big Apple is rotting-literally. Just the biological threat from those things down there alone is enough to make you both sicker than you are-not to mention the wounds you've suffered. We know of a group that was hiding out in a publisher's building on Broadway. One zombie managed to get inside. They destroyed it before it could murder any of them, but the disease on the corpse killed them all within days.'
Jim whistled. 'I never even considered that, and I've had some pretty close contact with these things.'
'You're very lucky. This other group wasn't.'
'How did you stay in contact with them?'
'Radio,' Quinn said. 'Hell, they radioed us even after they were dead.'
Stern put his pen back in his shirt pocket. 'I think you'll both be okay, though I want to keep an eye on that shoulder of yours. I'm giving you some strong antibiotics to help with the infection, but both of you are to take it easy for at least a week. Everyone pulls their own weight here, and you'll have plenty to do soon, depending upon your skills-so think of this as a one-week vacation.'
Jim nodded.
'Besides,' Stern said softly, 'I imagine you'd like to spend some time with your son.'
Jim blinked the tears away. 'You don't know how bad.'
'Believe me, Mr. Thurmond, I do.'
'If you guys don't mind,' Quinn said, 'I'm going to hit the sack. Been up for over twenty-four hours now and I'm pretty wiped out.'
Jim stood up and shook the pilot's hand.
'I just want to thank you again for saving us. If you and your partner hadn't shown up when you did-well, let's just say I thought we were done for.'
'Don't sweat it. Besides, we almost killed you ourselves with the U.B.R.D.'
'What the hell is that thing anyway? My head still hurts from it.'
'A remarkable device,' Stern breathed. 'Basically, it utilizes ultrasonic sound as a weapon.'
'The doc can explain it better than me,' Quinn said,
'so I'll let him take over. I'm sure we'll see each other around. This building is big, but it ain't that big. See ya, Danny!'
Danny waved. His fingers and mouth were stained red from the lollipop.
'Bye, Mr. Quinn! Thank you for helping us.'
After he left, Jim turned to the doctor.
'So it's a weapon?'
'Oh, yes,' Stern replied, 'and a very useful one at that. The technology was a safety feature, used to keep birds away from aircraft, farms, buildings, and such. They are very sensitive to sound, you see, much more so than a human or even a dog. It's really quite extraordinary.
They have a strong hearing ability. It assists them while hunting and helps them communicate with each other while in flight. Our device turns that strength into a weakness.'
'You're telling me it gives them an ear ache?'
The doctor chuckled. 'Not quite. It does much more than that. Ultrasonic sound creates extreme heat, and disrupts the nerves when played at a high frequency. It actually damages the living cells in a body. In the case of the birds, because of their sensitivity to sound, the mechanism's effects are greatly magnified. The stress forces them to flee. That's how it was used in commercial and military aviation. In our case, we simply cranked it up a notch, to use one of my grandson's favorite expressions. We broadcast at 1MHz, which virtually destroys a zombie bird's brain, and thus, destroys the zombie itself.'
'But why?' Jim asked. 'Why does it work on just the birds and not the other zombies? And I thought you said it only worked on living cells?'
'As for why it works on their brains even when the cells are dead-we can only speculate. These things, whatever they may be, seem to originate in their host's brain. It is my theory, and the theory of my associate, Dr. Maynard, who I'm sure you'll meet later, that deep within the host's brain, these entities may reactivate some of those dead cells and tissue. That's what gives them their mobility and reasoning capacity. The U.B.R.D. causes a loss of function in those reactivated cells inside a zombie bird's brain because of that sensitivity to sound, and because of the placement of their ears in relation to their brains.'
Danny watched his father and the doctor talk. His eyes never left Jim.
'Going back to your first question,' Stern continued, 'we simply don't know. The effect is sporadic on the human zombies-it acts as a deterrent, but it doesn't incapacitate or destroy them. Probably because they don't have
