Life in these worlds was rhythmically divided by the tides. During the nocturnal tides the bird-clouds all slept on the waves. During the day-time tides they indulged in aerial sports and religious exercises. But twice a day, when the land was dry, they cultivated the drenched ooze, or carried out in their cities of concrete cells all the operations of industry and culture. It was interesting to us to see how ingeniously, before the tide's return, all the instruments of civilization were sealed from the ravages of the water.
We supposed at first that the mental unity of these little avians was telepathic, but in fact it was not. It was based on the unity of a complex electromagnetic field, in fact on "radio" waves permeating the whole group. Radio, transmitted and received by every individual organism, corresponded to the chemical nerve current which maintains the unity of the human nervous system. Each brain reverberated with the ethereal rhythms of its environment; and each contributed its own peculiar theme to the complex pattern of the whole. So long as the flock was within a volume of about a cubic mile, the individuals were mentally unified, each serving as a specialized center in the common "brain." But if some were separated from the flock, as sometimes happened in stormy weather, they lost mental contact and became separate minds of very low order. In fact each degenerated for the time being into a very simple instinctive animal or a system of reflexes, set wholly for the task of restoring contact with the flock.
It may easily be imagined that the mental life of these composite beings was very different from anything which we had yet encountered. Different and yet the same. Like a man, the bird-cloud was capable of anger and fear, hunger and sexual hunger, personal love and all the passions of the herd; but the medium of these experiences was so different from anything known to us that we found great difficulty in recognizing them.
Sex, for instance, was very perplexing. Each cloud was bisexual, having some hundreds of specialized male and female avian units, indifferent to one another, but very responsive to the presence of other bird-clouds. We found that in these strange multiple beings the delight and shame of bodily contact were obtained not only through actual sexual union of the specialized sexual members but, with the most exqui site subtlety, in the aerial interfusion of two flying clouds during the performance of courtship gymnastics in the air.
More important for us than this superficial likeness to ourselves was an underlying parity of mental rank. Indeed, we should not have gained access to them at all had it not been for the essential similarity of their evolutionary stage with that which we knew so well in our own worlds. For each one of these mobile-minded clouds of little birds was in fact an individual approximately of our own spiritual order, indeed a very human thing, torn between the beast and the angel, capable of ecstasies of love and hate toward other such bird-clouds, capable of wisdom and folly, and the whole gamut of human passions from swinishness to ecstatic contemplation.
Probing as best we could beyond the formal similarity of spirit which gave us access to the bird-clouds, we discovered painfully how to see with a million eyes at once, how to feel the texture of the atmosphere with a million wings. We learned to interpret the composite percepts of mud-flats and marshes and great agricultural regions, irrigated twice daily by the tide. We admired the great tide-driven turbines and the system of electric transport of freight. We discovered that the forests of high concrete poles or minarets, and platforms on stilts, which stood in the shallowest of the tidal areas, were nurseries where the young were tended till they could fly.
Little by little we learned to understand something of the alien thought of these strange beings, which was in its detailed texture so different from our own, yet in general pattern and significance so similar. Time presses, and I must not try even to sketch the immense complexity of the most developed of these worlds. So much else has still to be told. I will say only that, since the individuality of these bird-clouds was more precarious than human individuality, it was apt to be better understood and more justly valued. The constant danger of the bird-clouds was physical and mental disintegration. Consequently the ideal of the coherent self was very prominent in all their cultures. On the other hand, the danger that the self of the bird-cloud would be psychically invaded and violated by its neighbors, much as one radio station may interfere with another, forced these beings to guard more carefully than ourselves against the temptations of the herd, against drowning the individual cloud's self in the mob of clouds. But again, just because this danger was effectively guarded against, the ideal of the world-wide community developed without any life-and-death struggle with mystical tribalism, such as we know too well. Instead the struggle was simply between individualism and the twin ideals of the world-community and the world-mind.
At the time of our visit world-wide conflict was already breaking out between the two parties in every region of the planet. The individualists were stronger in one hemisphere, and were slaughtering all adherents of the world-mind ideal, and mustering their forces for attack on the other hemisphere. Here the party of the world-mind dominated, not by weapons but by sheer radio-bombardment, so to speak. The pattern of ethereal undulations issuing from the party imposed itself by sheer force on all recalcitrants. All rebels were either mentally disintegrated by radio-bombardment or were absorbed intact into the communal radio system. The war which ensued was to us astounding. The individualists used artillery and poison gas. The party of the world-mind used these weapons far less than the radio, which they, but not their enemies, could operate with irresistible effect. So greatly was the radio system strengthened, and so adapted to the physiological receptivity of the avian units, that before the individualists had done serious harm, they found themselves engulfed, so to speak, in an overwhelming torrent of radio stimulation. Their individuality crumbled away. The avian units that made up their composite bodies were either destroyed (if they were specialized for war), or reorganized into new clouds, loyal to the world-mind.
Shortly after the defeat of the individualists we lost touch with this race. The experience and the social problems of the young world-mind were incomprehensible to us. Not till a much later stage of our adventure did we regain contact with it.
Others of the worlds inhabited by races of bird-clouds were less fortunate. Most, through one cause or another, came to grief. In many of them the stresses of industrialism or of social unrest brought about a plague of insanity, or disintegration of the individual into a swarm of mere reflex animals. These miserable little creatures, which had not the power of independent intelligent behavior, were slaughtered in myriads by natural forces and beasts of prey. Presently the stage was clear for some worm or amoeba to reinaugurate the great adventure of biological evolution toward the human plane.
In the course of our exploration we came upon other types of composite individuals. For instance, we found that very large dry planets were sometimes inhabited by populations of insect-like creatures each of whose swarms of nests was the multiple body of a single mind. These planets were so large that no mobile organism could be bigger than a beetle, no flying organism bigger than an ant. In the intelligent swarms that fulfilled the part of men in these worlds, the microscopic brains of the insect-like units were specialized for miscroscopic functions within the group, much as the members of an ant's nest are specialized for working, fighting, reproduction, and so on. All were mobile, but each class of the units fulfilled special "neurological" functions in the life of the whole. In fact they acted as though they were special types of cells in a nervous system.