Yet not circulating for ever. Because the electric entities that human beings called childrims could not change. So nothing was more vulnerable to change than they.
Temperatures across the tropical continent of Campannlat varied greatly at any one time. On a mild day in the summer, while Loilanun sat playing listlessly with her young son, the ground temperature in Oldorando climbed several degrees above zero. Only a comparatively few miles north, by Lake Dorzin, there might be ten degrees of frost. In summer, when the sentinels worked day and night, there was no frost at all in sheltered parts, and cereal crops grew.
Three thousand miles from Oldorando, in the Nktryhk, daily temperatures showed wide variation, from minus twelve degrees centigrade to minus one hundred and fifty degrees, about the temperature at which krypton turns to liquid.
Change accumulated, at first as what may be termed latent change. Then its effects were rapid, as temperature gradients in the upper atmosphere responded to increased radiations from Freyr. The process was steady but quantal. On one occasion, Earth Observation Station Avernus recorded a twelve-degree rise in temperature at a 16.6-mile equatorial altitude within the course of an hour.
With this warming up, stratospheric circulation increased strongly, and the planet was swept by storms. Jet streams were observed over Nktryhk travelling at speeds in excess of two hundred seventy-five miles per hour.
Suddenly, the childrims were no more.
The beginnings of what was to spell a renascence for mankind and animals brought disaster for the childrims. The conditions that created them dispersed between one year and the next. Their vortices of piezoelectric dusts and charged particles were too fragile to survive a more dynamic system. They were gone, leaving behind them evanescent trails of sparks in the rarefied upper air. The sparks soon died.
Yuli and Loil Bry looked in vain for the childrims. Laintal Ay soon forgot he had ever seen them.
Groups of phagors were emerging under the greenish sky common at that altitude, where the sentinels—when not buried in cloud—directed their rays through multitudinous ice crystals. The phagors, stalluns and gillots alike, moved into position with their inhuman gait. Many had birds perched on their shoulders or flying just above them. The birds and the phagors were white, the terrain white or brown and exsiccated black, the sky beyond livid green. The living things were outlined against the Hhryggt Glacier.
The course of the glacier was divided at one point by a massif of plutonic rock which, like an infernal castle, had withstood centuries of siege. The ice had scoured its walls, yet it survived, rearing its bunched towers towards the sky. Where the ice river fell away was a firn-covered plateau. Here stood the ancipital leader, immobile, while the cohorts of his crusade assembled.
It was the components belonging to the kzahhns of Hrastyprt who first decided to bring destruction upon the Sons of Freyr who lived in the remote plains. The young kzahhn was Hrr-Brahl Yprt. He would lead the crusade. It was his grandstallun, the great Kzahhn Hrr-Tryhk Hrast, who had been destroyed by those distant Sons. Under Hrr-Brahl Yprt would the legions ride forth in revenge.
For under Hrr-Brahl Yprt the component had prospered, regaining strength lost since Freyr last burned the world. Force of numbers as much as conscious decision urged it from its altitudinous fastnesses to begin this migration of irresistible scale.
Vengeance moved in their harneys, but action was triggered by favourable temperature gradients in the stratosphere. A heat message thrilled along the five-hundred-mile length of the glacier, as it spilled down from the airless plateau of High Nktryhk to the excoriated valleys east of the Oldorandan plain, drawing out ancipitals from its eaves and crevices.
Hrr-Brahl Yprt waited, motionless. He too heard the heat message across his air-octave.
The precursor of major climatic change activated other forms of life in the region, forms on which the phagors were in part dependent for protein. Protognostic tribes called Madis also occupied the boulder-strewn land of the glaciers. Gaunt, perpetually undernourished, they too began to resume a nomadic habit. They drove before them goat and arang, the quadruped that lived on lichens or rocklice. The Madis sought lower pastures. But they would not travel before the phagor crusade left the way clear.