Soon it would be time to shift from one vision to another. He felt the movement of sandtrout as a movement within himself. Fremen had lived with the strange creatures for generations, knowing that if you risked a bit of water as bait, you could lure them into reach. Many a Fremen dying of thirst had risked his last few drops of water in this gamble, knowing that the sweet green syrup teased from a sandtrout might yield a small profit in energy. But the sandtrout were mostly the game of children who caught them for the Huanui. And for play.
Leto shuddered at the thought of what that play meant to him now.
He felt one of the creatures slither across his bare foot. It hesitated, then went on, attracted by the greater amount of water in the qanat.
For a moment, though, he'd felt the reality of his terrible decision. The sandtrout glove. It was the play of children. If one held a sandtrout in the hand, smoothing it over your skin, it formed a living glove. Traces of blood in the skin's capillaries could be sensed by the creatures, but something mingled with the blood's water repelled them. Sooner or later, the glove would slip off into the sand, there to be lifted into a spice-fiber basket. The spice soothed them until they were dumped into the deathstill.
He could hear sandtrout dropping into the qanat, the swirl of predators eating them. Water softened the sandtrout, made it pliable. Children learned this early. A bit of saliva teased out the sweet syrup. Leto listened to the splashing. This was a migration of sandtrout come up to the open water, but they could not contain a flowing qanat patrolled by predator fish.
Still they came; still they splashed.
Leto groped on the sand with his right hand until his fingers encountered the leathery skin of a sandtrout. It was the large one he had expected. The creature didn't try to evade him, but moved eagerly onto his flesh. He explored its outline with his free hand - roughly diamond-shaped. It had no head, no extremities, no eyes, yet it could find water unerringly. With its fellows it could join body to body, locking one on another by the coarse interlacings of extruded cilia until the whole became one large sack-organism enclosing the water, walling off the "poison" from the giant which the sandtrout would become: Shai-Hulud.
The sandtrout squirmed on his hand, elongating, stretching. As it moved, he felt a counterpart elongating and stretching of the vision he had chosen. This thread, not that one. He felt the sandtrout becoming thin, covering more and more of his hand. No sandtrout had ever before encountered a hand such as this one, every cell supersaturated with spice. No other human had ever before lived and reasoned in such a condition. Delicately Leto adjusted his enzyme balance, drawing on the illuminated sureness he'd gained in spice trance. The knowledge from those uncounted lifetimes which blended themselves within him provided the certainty through which he chose the precise adjustments, slaving off the death from an overdose which would engulf him if he relaxed his watchfulness for only a heartbeat. And at the same time he blended himself with the sandtrout, feeding on it, feeding it, learning it. His trance vision provided the template and he followed it precisely.
Leto felt the sandtrout grow thin, spreading itself over more and more of his hand, reaching up his arm. He located another, placed it over the first one. Contact ignited a frenzied squirming in the creatures. Their cilia locked and they became a single membrane which enclosed him to the elbow. The sandtrout adjusted to the living glove of childhood play, but thinner and more sensitive as he lured it into the role of a skin symbiote. He reached down with the living glove, felt sand, each grain distinct to his senses. This was no longer sandtrout; it was tougher, stronger. And it would grow stronger and stronger... His groping hand encountered another sandtrout which whipped itself into union with the first two and adapted itself to the new role. Leathery softness insinuated itself up his arm to his shoulder.
With a terrible singleness of concentration he achieved the union of his new skin with his body, preventing rejection. No corner of his attention was left to dwell upon the terrifying consequences of what he did here. Only the necessities of his trance vision mattered. Only the Golden Path could come from this ordeal.
Leto shed his robe and lay naked upon the sand, his gloved arm outstretched into the path of migrating sandtrout. He remembered that once he and Ghanima had caught a sandtrout, abraded it against the sand until it contracted into the child-worm, a stiff tube, its interior pregnant with the green syrup. One bit gently upon the end and sucked swiftly before the wound was healed, gaining the few drops of sweetness.