Julian pressed a switch, and a beam of dazzling brilliance bored down the tunnel before them. The vast central roadway stretched out like a dirigible hangar of infinite length. Here and there, the upsweeping curves of the walls were pierced with side-turnings; mysterious, gaping mouths whose immenseness was dwarfed only by the proportions of the main artery. Of traffic, there was little at the present, but such machines as were visible scuttled along with a methodical orderliness, keeping to the right of the track and paying no attention either to pursuer or pursued.
'Why don't they attack us?' Roy wondered.
'Too specialised,' replied Ril. 'Their whole organisation is worked on a basis of calculation, precision and instinct. They know, for instance, that there is danger from the red stalking-machines outside; that danger is calculated and allowed for. But when they face us, they are up against the incalculable, and their instincts are not any help to them. For centuries, perhaps, they have not been called upon to cope with the unexpected.'
'But they attacked and captured us in the first place.'
'True, but then they were in the open, where dangers might be expected and their instinct was to overcome a challenge. It requires more than instinct and simple calculation to grasp the idea of one of their own machines being turned against them. You notice that even the one we are following has shown no sign of perturbation; it has just kept steadily on its way and paid no attention to anything else.'
'Then we are safe from interference? All we have to do is to recapture Jessica when we reach the other machine, and march out with her.'
Ril looked doubtful. It seemed unlikely that it would be as simple as that.
'We are all right, I think, until we are discovered by the central intelligence. We can't tell what will happen then.'
'But how do you know there is a central intelligence?'
Ril lifted one hand from the controls of the racing vehicle, and waved it in an expressive sweep.
'Something must control all this. Besides, you remember the machine which wrote on the floor—it was obviously designed for brain-work of some kind. It had no legs to move about on. It was a calculating machine—a kind of composite-thinking mechanism. Somewhere in this ant-mountain there must be a super-calculator, capable not only of working from known factors, but of reasoning from probabilities; a kind of central brain, of which our questioner was a mere subsidiary.'
'It sounds too improbable.'
'I don't think so. Since the insects had even more natural obstacles to overcome than man had, they must, of necessity, use more involved apparatus.'
While Ril spoke, they gradually gained on the machine ahead. Now, a bare twenty yards separated the two. Julian already had his hands on the control-levers of the tentacles, and was ready to send them coiling out the moment the range permitted. The leader turned, with a sudden swerve, down a passage to the left. Only by skilful manipulation did Ril avoid overshooting the corner, but he succeeded, and they gained yet another couple of yards. The three men grew more tense as the distance lessened. Julian's knuckles were white on the levers, and his face strained. Roy again thrust his head and shoulders through the top panel, and held his tube ready for action. Then, with disconcerting suddenness, the passage walls fell away and they sped out into a large, circular hall.
Roy had a glimpse of serried ranks of the white metal machines, gleaming and glittering in the rays of their lamp; then his eyes rose to the structure which dominated the whole vast room. It stood, raised on a dais in the exact centre—a huge, metallic shape, sprouting with a multitude of shining feelers. At that moment, Julian went into action. Judging his distance to a nicety, he sent a tentacle whipping round one of the rear legs of Jessica's captor.
Simultaneously, Ril slowed their machine, and there came a jerk which almost dislodged Roy from his perch. The legs of the leader crumpled beneath it, and the shining belly met the ground with a thud. Julian, with the full power of the attached tentacle, began to draw it back towards them. From his vantage-point, Roy sliced with a pencil-thick ray at the roots of the feelers which bound Jessica. The whole affair had taken place so quickly that they had been unmolested; but as the last strand parted, there came an ominous stirring in the ranks of the surrounding machines.
Ril's voice rose insistently. 'Quick! Get that central globe!'
Roy perceived that the many feelers around it had sprung into furiously writhing signals. With sweeps of his ray at full power, he carved it into sections. As the parts fell, he saw the outflow of myriads of ants, running in glistening streams across the floor.
'Too late!' cried Ril. 'It's given the order.'
Roy swung his beam around the closing circle of machines, while the tentacles under Julian's control sought and grasped the prostrate form of Jessica. They snatched her from the ground a split second before the insect hordes swept the spot.
'We've got to run for it,' Ril called up, as he manoeuvred their craft to the right-about. 'Clear a way to the passage.'
The few machines in their path were swiftly dealt with, but while Roy's attention was taken aside, the rest of the circle was closing in.
'Full speed!' he roared down to the dwarf.
They tore forward with a jerk, the light and Roy's heat-ray blazing ahead of them. Once in the comparative safety of the corridor, he turned around and devoted his attention to hindering the pursuit. Dozens fell to his ray, but he saw that, in spite of his destruction, the mass was gaining. At a sudden idea, he thrust the power of his tube down a couple of notches, and gave an exclamation of satisfaction at the result. The machines, instead of being blotted out, were now being fused into immobility and thus presenting considerable difficulties to the advance of those in the rear. A second inspiration struck him, and he called to Ril to slow down.
He swung his ray across the passage and rendered useless the first rank of the pursuers. As those behind came climbing over them, he swung the ray back along the line so that they were fused above their fellows. Still more came scrambling over, and again the ray swept across. A grim smile of success twitched his mouth as he steadily continued his tactics. At great speed, he was building a solid wall of fused metal between himself and the pursuers. It was but a short time before it blocked the passage from the floor to the curved roof.
The moment it was complete, he jumped to the ground and ran forward to where Jessica's inert form rested in the grip of the feelers. He was thankful that she had been unconscious throughout the rescue. It was the work of a few seconds to strip off the clinging remnants of her captor's tentacles and lift her up to Julian, who had taken his place at the panel opening. Swinging himself hurriedly aboard, he called to Ril for full speed. There was no telling how long the fused wall would hold.
The remaining length of passage was covered without incident, or even sight of other machines, but they emerged into the main traffic artery to find a different state of affairs. They had last seen it almost empty; now, it was crowded. A number of mechanisms rushed at them with antagonistic intent, and were promptly rayed before they reached a dangerous distance. Following them were others; but by no means all the machines in sight were concerned in the attack. The majority continued peacefully to go about their appointed tasks. Either the alarm had not been intended for all. or else it had been cut short before it became general. Whatever the cause, the result was a great jostling and tangling of machines at cross-purposes. The attackers were obstructed and hindered at every turn by the instinctive way in which the others pursued their routine work.