Ruiz-Sanchez changed the carafe of fresh water in the niche beside the hammock, went into the hall, and donned boots, mackintosh and waterproof hat. The night sounds of Lithia burst in upon him as he opened the stone door, along with a gust of sea air bearing the characteristic halogen odor always called "salty." There was a thin drizzle falling, making halos around the lights of Xoredeshch Sfath. Far out, on the water, another light moved. That was probably the coastal side-wheeler to Yllith, the enormous island which stood a-thwart the Upper Bay , barring the Gulf of Sfath as a whole from the equatorial sea.
Outside, Ruiz-Sanchez turned the wheel which extended bolts on every margin of the door. Drawing from his mackintosh a piece of soft chalk, he marked on the sheltered tablet designed for such uses the Lithian symbols which meant "Illness is here." That would be sufficient. Anybody who chose to could open the door simply by turning the wheel-the Lithians had never heard of locks-but the Lithians, too, were overridingly social beings, who respected their own conventions as they respected natural law.
That done, Ruiz-Sanchez set out for the center of the city and the Message Tree. The asphalt streets shone in the yellow lights cast from windows, and in the white light of the mantled, wide-spaced street lanterns. Occasionally he passed the twelve-foot, kangaroo-like shape of a Lithian, and the two exchanged glances of frank curiosity, but there were not many Lithians abroad now. They kept to their houses at night, doing Ruiz-Sanchez knew not what. He could see them frequently, alone or by twos or threes, moving behind the oval windows of the houses he passed. Sometimes they seemed to be talking.
What about?
It was a nice question. The Lithians had no crime, no newspapers, no house-to-house communications systems, no arts that could be differentiated clearly from their crafts, no political parties, no public amusements, no nations, no games, no religions, no sports, no cults, no celebrations. Surely they didn't spend every waking minute of their lives exchanging knowledge, making things go, discussing philosophy or history, or planning for tomorrow! Or did they? Perhaps, Ruiz-Sanchez thought suddenly, they simply went inert once they were inside their jugs, like so many pickles! But even as the thought came, the priest passed another house, and saw their silhouettes moving to and fro…
A puff of wind scattered cool droplets in his face. Automatically, he quickened his step. If the night were to turn out to be especially windy, there would doubtless be many voices coming and going in the Message Tree. It loomed ahead of him now, a sequoialike giant, standing at the mouth of the valley of the River Sfath-the valley which led in great serpentine folds into the heart of the continent, where Gleshchtehk Sfath, or Blood Lake in English, poured out its massive torrents.
As the winds came and went along the valley, the tree nodded and swayed-only a little, but that little was enough. With every movement, the tree's root system, which underlay the entire city, tugged and distorted the buried crystalline cliff upon which the city had been founded, as long ago in Lithian pre-history as was the founding of Rome on Earth. At every such pressure, the buried cliff responded with a vast heart-pulse of radio waves-a pulse detectable not only all over Lithia, but far out in space as well. The four Commission members had heard those pulses first on shipboard, when Alpha Arietis, Lithia's sun, was still only a point of light ahead of them, and had looked into each other's faces with eyes gleaming with conjecture.
The bursts, however, were sheer noise. How the Lithians modulated them to carry information-not only messages, but the amazing navigational grid, the planet-wide time-signal system, and much more-was something as remote from Ruiz-Sanchez' understanding as affine theory, although Cleaver said it was all perfectly simple once you understood it. It had something to do with semi-conduction and solid-state physics, which (again according to Cleaver) the Lithians understood better than any Earthman.