More double Falls could be anticipated: on the thirty-first day after First Fall, Thread would sweep across Karachi camp and the tip of the Kahrain peninsula; three days later a single land corridor would range from Kahrain across Paradise River Stake, while a second Fall would pass harmlessly at sea well above the tip of Cibola Province. After another three days, a dangerous double would hit Boca Stake and the thick forests of lower Kahrain and Araby, stocks of the one real wood vitally needed to shore up mine pits at busy Karachi Camp and Drake’s Lake.

Ezra spent hours in the booth that housed the link with the Yokohama’s mainframe, scanning the naval and military histories to find some means of combating the menace. He also sought, with much less optimism, obscure equations or devices that might be able to alter the orbit of the planet. Then the next Fall could, perhaps, be avoided. Meanwhile, however, the present pass had seeded Pern’s orbit with spirals of the encapsulated Thread, a danger that the colonists would have to face no matter what. He also did comparisons with data from Kitti’s program, delving into science files, using his security ID to access secret or “need to know” information. He was waiting, too, for the probe’s findings to be relayed back to him. And because everyone knew where to find Ezra, he often intercepted complaints and minor problems that would have added unnecessary burdens to the admiral and the governor.

Kenjo was sent on three more missions, each time trying to find a more efficient way of destroying enough Thread in space to justify the expenditure of precious fuel. The gauges on the Mariposa dropped only slightly with each trip, and Kenjo was commended on his economy. Drake was openly envious of the space pilot’s skill.

“Jays, man,” Drake would say. “You’re driving it on the fumes!”

Kenjo would nod modestly and say nothing. He was, however, rather relieved that he had not managed to transfer all the fuel sacks to their hiding place at Honshu. All too soon, he would have to broach that supply to ensure continued trips into space. Only there did he feel totally aware and alive in every sense and nerve of his body.

But each time he brought back useful information. Thread, it turned out, traveled in a pod that burned away when it hit the atmosphere of Pern, leaving an inner capsule. About 15,000 feet above the surface, the inner capsule opened into ribbons, some of which were not thick enough to survive in the upper reaches. But, as everyone at Landing well knew, plenty fell to the surface.

Most of the sleds were unpressurized, so they had an effective ceiling of 10,000 feet. There was still only one way to clear the Thread from the skies: by flamethrowers.