At every pass they made, thousands of ants shrivelled and became no more than light ash; but still they pushed relentlessly on, marching blindly to certain death. Their centralisation had disappeared with the wreckage of their machine, and now they were left only with the old instinct to attack. There was little real danger; even Julian's lesser ray could have wiped them all out in five minutes. But there came an interruption: the familiar clatter of the metal door. Del turned to see a trio of machines scuttering in through the opening. He pushed up his ray to full power and cut away the fast-moving legs with one sweep. The metal bodies dropped, and impeded those behind.
Del switched a withering blast of heat on the lintel of the doorway. More by luck than knowledge, he succeeded in melting away the supporting catches, and the metal sheet crashed down, bisecting two entering machines as it fell. Kal sprang to Del's side and trained a ray on one of the stranded machines, turning it incandescent; but already, from the broken halves in the doorway, more black streams of insects were flooding to the attack. Switching his ray to low power lest he should melt the door behind, Del swept a myriad of infuriated ants into eternity. Julian and Ril, behind him, continued the destruction of the first swarm.
Kal dealt rapidly with all three of the powerless machines. Each was rendered red-hot, and its crew incinerated before it could escape. Then he joined Del in repelling the second attack. There came a pandemonium of battering against the door as the machines outside attempted to crash their way in, but the metal sheet was massive enough to defy their most strenuous efforts. The slaughter of the ants was quickly completed. The four tube-holders rayed, on low power, every corner of the great hall, to make certain that none had escaped. Only when they were satisfied that the last ant was wiped out did they have opportunity to pause and consider.
'We'll have to get out of this—and quick!' exclaimed Roy.
'But how? There's no way but the door.'
'Burn our way out,' replied Del. 'We're not far from the open, here. You remember we were near the entrance when they turned in here. Which direction was it?'
'The left wall,' said Roy, definitely. 'But we can't burn through that—all the molten stuff will run back on us in here.'
Del shook his head. 'We can get rid of that.'
A heat-ray was rigged up, pointing directly down at the floor, and then switched on to full power. For ten or twelve seconds the circle of earth below it boiled and seethed furiously, while waves of heat rolled through the cavern. Then, abruptly, it vanished, leaving only a dark hole. Roy stared.
'What happened?' he inquired. Del, switching off the tube, smiled at his astonishment.
'There's no magic about it,' he answered him. 'You see, this place we are in is nothing more or less than a mammoth anthill. But ant-hills have workings extending below ground as well as above. We simply melted through the roof of the level below us, and the residue has flowed through the passages down there.'
Approaching as closely as possible, Del began to cut a trench from the foot of the wall to the lip of the newly-drilled hole.
His back was towards the door, and it was only a warning scream from Jessica which saved him from the fate of the luckless Numan. All looked where she pointed. A black carpet of ants was spreading towards them, streaming between the base of the door and the ill-fitting threshold in their hundreds of thousands.
Del turned like a flash, and his tube, still at full power, swept them to instant annihilation. Simultaneously, a corner of the door became a ragged hole in the metal, its edges dripping molten blobs to the floor. Del set Julian to guard the vulnerable spot and turned, with renewed energy, to the drilling of the escape tunnel.
Muffled as much as possible against the heat, he stood back on the far side and trained his ray forward. The solid wall began to liquefy. It oozed and dripped down into the trench he had prepared, flowing along until it poured to unknown depths through the hole in the floor. The operation took no more than a few minutes, but the belching waves of heat reduced them, in even so short a time, to the limit of their endurance. The hot air of the cavern became all but unbreathable. The radiation seemed to scorch them even through their clothing when, to Del's surprise, daylight broke through at ten to a dozen yards distance.
'We've been fortunate,' he remarked, shutting off his tube. 'We were nearer the outside than I suspected. I've drilled the shaft on a slant so that it will drain, but it will be some hours before it is passable. Now we must get to work—when we've made that doorway safe.'
Narrowing his beam, he cut an overhanging piece of the roof so that it fell squarely in front of the hole in the door. Satisfied that the entrance was now completely blocked, he turned his attention to the row of derelict time-travellers.
'These,' he said, with a wave of his hand, 'are the only means we have of regaining our own time. We cannot take them bodily with us. But we must select the more intricate and essential parts, and carry them off. We may be able to discover material for framework, but such things as vacuum tubes, Lestrange batteries, light-impulse cells and the like, would be a great labour to construct—even if we could do so, which is doubtful.'
Very little of Roy's machine was worthy of salvage. When he had extracted his two undamaged Lestrange batteries, he walked over to the two Numen, who were standing helplessly by their crumpled vehicle, and directed them to unbolt such impulse cells as remained intact. Then he became interested in the other machines. Among those unclaimed by anyone present stood two dented metal cubes. Del came over to join him as he pulled on the door of one. It came grudgingly ajar, hanging askew on the twisted frame, and a breath of corruption sent the two men staggering back a pace. Holding his breath, Roy reapproached and peered inside. The shrivelled body of a man. in a far state of decomposition, lay huddled into one of the farther corners.
'Poor devil,' he muttered. 'At least, we've been luckier than he was.'
Del, with his tube at low power, cremated the decaying body, and after waiting a moment for the air to clear, they both entered. One wall was lined with rows of tubes and resistances, while on another were control-panels attended with tortuous convolutions of wiring. Roy peered hopefully among the serried switches and dials for some clue to the machine's date of origin, but without success. Del pondered silently over the mechanism for a while. An expression of wonder came over his face.
'What is it?'
Del answered half to himself. 'I considered it impossible.'
'What do you mean?'
'This vehicle is radically different from ours. It does not plunge instantaneously through the time-flow. Instead, it has the property of slowing down its contents, so that the world outside slips by at high speed by comparison. A slow, inefficient machine—but it worked.'
'I don't understand.'
'I mean that both our machines, yours and mine, work similarly to the extent that they insulate us entirely from time—that is to say, ages pass by us in a flash and we are not affected. But this is not a complete insulating machine; it works with a kind of drag action. For instance, if the operator turns this main dial to indicate a speed half-way between the normal time-flow and complete insulation, events inside his chamber will take exactly twice as long to happen as they would in the outer world. During the period which seems an hour to him, the events of two hours will take place outside. If he turns the dial farther, the events of a week, or a year, flash past in what appears to be an hour. See, he even has a window through which he can watch the happenings of the world fly past.'
Roy noticed a square of glass set in one wall.