The pilot screamed in pain. "No—I swear it!"

"How does the Manhattan Crystal furnish power for New York?"

"I don't know."

"It's transmission of power, isn't it?" demanded Dave, jerking the wounded arm again.

"I—"

"Good. That's what I thought. Transmission from one crystal to another. They blow them up the same way?"

The pilot nodded, weakly.

"So we don't manufacture the crystals in the nuclear laboratories. You and your gang deliver them like Santa Claus, coming down the chimney!"

The pilot nodded again.

"Now—where is this thing run from?"