"Then what?" Halleck asked.

Kynes shrugged. "Wait for the worm to leave."

"That's all?" Paul asked.

"When the worm has gone, one may try to walk out," Kynes said. "You must walk softly, avoid drum sands, tidal dust basins—head for the nearest rock zone. There are many such zones. You might make it."

"Drum sand?" Halleck asked.

"A condition of sand compaction," Kynes said. "The slightest step sets it drumming. Worms always come to that."

"And a tidal dust basin?" the Duke asked.

"Certain depressions in the desert have filled with dust over the centuries. Some are so vast they have currents and tides. All will swallow the unwary who step into them."

Halleck sat back, resumed strumming the baliset. Presently, he sang:

He broke off, leaned forward. "Dust cloud ahead, Sire."

"I see it, Gurney."

"That's what we seek," Kynes said.

Paul stretched up in the seat to peer ahead, saw a rolling yellow cloud low on the desert surface some thirty kilometers ahead.

"One of your factory crawlers," Kynes said. "It's on the surface and that means it's on spice. The cloud is vented sand being expelled after the spice has been centrifugally removed. There's no other cloud quite like it."

"Aircraft over it," the Duke said.

"I see two... three... four spotters," Kynes said. "They're watching for wormsign."

"Wormsign?" the Duke asked.

"A sandwave moving toward the crawler. They'll have seismic probes on the surface, too. Worms sometimes travel too deep for the wave to show." Kynes swung his gaze around the sky. "Should be a carryall wing around, but I don't see it."

"The worm always comes, eh?" Halleck asked.

"Always."

Paul leaned forward, touched Kynes' shoulder. "How big an area does each worm stake out?"

Kynes frowned. The child kept asking adult questions.

"That depends on the size of the worm."

"What's the variation?" the Duke asked.

"Big ones may control three or four hundred square kilometers. Small ones—" He broke off as the Duke kicked on the jet brakes. The ship bucked as its tail pods whispered to silence. Stub wings elongated, cupped the air. The craft became a full 'thopter as the Duke banked it, holding the wings to a gentle beat, pointing with his left hand off to the east beyond the factory crawler.

"Is that wormsign?"

Kynes leaned across the Duke to peer into the distance.

Paul and Halleck were crowded together, looking in the same direction, and Paul noted that their escort, caught by the sudden maneuver, had surged ahead, but now was curving back. The factory crawler lay ahead of them, still some three kilometers away.

Where the Duke pointed, crescent dune tracks spread shadow ripples toward the horizon and, running through them as a level line stretching into the distance, came an elongated mount-in-motion—a cresting of sand. It reminded Paul of the way a big fish disturbed the water when swimming just under the surface.

"Worm," Kynes said. "Big one." He leaned back, grabbed the microphone from the panel, punched out a new frequency selection. Glancing at the grid chart on rollers over their heads, he spoke into the microphone: "Calling crawler at Delta Ajax niner. Wormsign warning. Crawler at Delta Ajax niner. Wormsign warning. Acknowledge, please." He waited.

The panel speaker emitted static crackles, then a voice: "Who calls Delta Ajax niner? Over."

"They seem pretty calm about it," Halleck said.

Kynes spoke into the microphone: "Unlisted flight—north and east of you about three kilometers. Wormsign is on intercept course, your position, estimated contact twenty-five minutes."

Another voice rumbled from the speaker: "This is Spotter Control. Sighting confirmed. Stand by for contact fix." There was a pause, then: "Contact in twenty-six minutes minus. That was a sharp estimate. Who's on that unlisted flight? Over."

Halleck had his harness off and surged forward between Kynes and the Duke. "Is this the regular working frequency, Kynes?"

"Yes. Why?"

"Who'd be listening?"

"Just the work crews in this area. Cuts down interference."

Again, the speaker crackled, then: "This is Delta Ajax niner. Who gets bonus credit for that spot? Over."

Halleck glanced at the Duke.

Kynes said: "There's a bonus based on spice load for whoever gives first worm warning. They want to know—"

"Tell them who had first sight of that worm," Halleck said.

The Duke nodded.

Kynes hesitated, then lifted the microphone; "Spotter credit to the Duke Leto Atreides. The Duke Leto Atreides. Over."

The voice from the speaker was flat and partly distorted by a burst of static: "We read and thank you."

"Now, tell them to divide the bonus among themselves," Halleck ordered. "Tell them it's the Duke's wish."

Kynes took a deep breath, then: "It's the Duke's wish that you divide the bonus among your crew. Do you read? Over."

"Acknowledged and thank you," the speaker said.

The Duke said: "I forgot to mention that Gurney is also very talented in public relations."

Kynes turned a puzzled frown on Halleck.

"This lets the men know their Duke is concerned for their safety," Halleck said. "Word will get around. It was on an area working frequency—not likely Harkonnen agents heard." He glanced out at their air cover. "And we're a pretty strong force. It was a good risk."

The Duke banked their craft toward the sandcloud erupting from the factory crawler. "What happens now?"

"There's a carryall wing somewhere close," Kynes said. "It'll come in and lift off the crawler."

"What if the carryall's wrecked?" Halleck asked.

"Some equipment is lost," Kynes said. "Get in close over the crawler, my Lord; you'll find this interesting."

The Duke scowled, busied himself with the controls as they came into turbulent air over the crawler.

Paul looked down, saw sand still spewing out of the metal and plastic monster beneath them. It looked like a great tan and blue beetle with many wide tracks extending on arms around it. He saw a giant inverted funnel snout poked into dark sand in front of it.

"Rich spice bed by the color," Kynes said. "They'll continue working until the last minute."

The Duke fed more power to the wings, stiffened them for a steeper descent as he settled lower in a circling glide above the crawler. A glance left and right showed his cover holding altitude and circling overhead.

Paul studied the yellow cloud belching from the crawler's pipe vents, looked out over the desert at the approaching worm track.

"Shouldn't we be hearing them call in the carryall?" Halleck asked.

"They usually have the wing on a different frequency," Kynes said.

"Shouldn't they have two carryalls standing by for every crawler?" the Duke asked. "There should be twenty-six men on that machine down there, not to mention cost of equipment."

Kynes said: "You don't have enough ex—"

He broke off as the speaker erupted with an angry voice: "Any of you see the wing? He isn't answering."

A garble of noise crackled from the speaker, drowned in an abrupt override signal, then silence and the first voice: "Report by the numbers! Over."

"This is Spotter Control. Last I saw, the wing was pretty high and circling off northwest. I don't see him now. Over."

"Spotter one: negative. Over."

"Spotter two: negative. Over."

"Spotter three: negative. Over."

Silence.

The Duke looked down. His own craft's shadow was just passing over the crawler. "Only four spotters, is that right?"