"By all the laws of logic, we have only to be on the alert for outside thoughts and stay within a few hundred yards of my car to be absolutely safe. Yet I'm alarmed by your intuition of danger. Please search your brain and try to discover the basis for your fear. I can't do it for you as well as you can do it for yourself."
The girl was silent. Her eyes closed. Her shield went up. She sat there beside him in the car, looking strangely like a beautiful overgrown child fallen asleep. Finally her sensitive lips twitched. For the first time she spoke aloud.
"Tell me, what is ten-point steel?"
"Ah," said Jommy Cross in satisfaction, "I'm beginning to understand the psychological factors involved. Mental communication has many advantages, but it cannot convey the extent, for instance, of a weapon's power as well as a picture on a piece of paper, or not even as well as by word of mouth. Power, size, strength and similar images do not transmit well."
"Go on."
"Everything I've done," Jommy Cross explained, "has been based on my father's great discovery of the first law of atomic energy – concentration as opposed to the old method of diffusion. So far as I know, Father never suspected the metal-strengthening possibilities, but, like all research workers who come after the great man and his basic discovery, I concentrated on details of development, based partly on his ideas, partly on ideas that progressively suggested themselves.
"All metals are held together by atomic tensions, which comprise the theoretical strength of that metal. In the case of steel, I called this theoretical potential one-point. As a comparison, when steel was first invented its strength was about two-thousand-point. New processes rapidly increased this to around one-thousand, then, over a period of hundreds of years, to the present human level of seven-hundred-and-fifty.
"Tendrilless slans have made five-hundred-point steel, but even that incredibly hard stuff cannot compare with the product of my application of atomic strain, which changes the very structure of the atoms and produces the almost perfect ten-point steel. An eighth of an inch of ten-point can stop the most powerful explosive known to human beings and tendrilless slans!"
Briefly, he described his attempted trip to the Moon and the mine that sent him scurrying home, badly smashed. He concluded: "The important tiling to remember there is that an atomic bomb obviously big enough to blow up a giant battleship did not penetrate a foot of ten-point, though the hull was badly dented and the engine room a shambles from transmitted shock."
Kathleen was gazing at him, her eyes shining. "What a silly fool I am," she breathed. "I've met the greatest living slan and I'm trying to fill him with the fears gathered from twenty-one years of living with human beings and then' comparatively infinitesimal powers and forces."
Jommy Cross shook his head smilingly. "The great man is not me, but my father – though he had his faults, too, the biggest one being lack of adequate self-protection. But that's true genius." The smile faded. "I'm afraid, though, that we'll have to make frequent visits, to this cave, and every one will be just as dangerous as this one. I have met John Petty very briefly, and what I've seen in your mind only adds to a picture of a ruthlessly thorough man. I know he's keeping a watch on this place, but really we cannot allow ourselves to be frightened by such a prospect. We'll stay only till dark this time – just long enough for me to examine the machinery. There's some food in the car that we can cook after I've had a little sleep. I'll sleep in the car, of course. But first, the machinery!"
Everywhere the big machines sprawled, like corpses, silent and moldering. Blast furnaces, great stamping machines, lathes, saws, countless engined tools, a half-mile row on tight row of machines, about thirty per cent completely out of commission, twenty per cent partially useless, and the rest usuable up to a point.
The unwinking, glareless lights made a shadowed world as they wandered along that valley of broken floor in and out among the machine hills. Jommy Cross was thoughtful.
'There's more here than I imagined – everything I have always needed. I could build a great battleship with the scrap metal alone; and they probably use it only as a means of trapping slans." His thought narrowed on her mind: "Tell me, you're sure there are only two entrances to this city?"
"There are only two entrances given on the list in Kier Gray's desk – and I've located no others."
He was silent, but he did not conceal the tenor of his thoughts from her. "Foolish of me to think again of your intuition, but I don't like to let a possible menace out of my mind till I've examined every connective probability."
"If there's a secret entrance," Kathleen volunteered, "it would take us hours to find it, and if we found one, we couldn't be sure there wouldn't be others, and so we'd feel no more secure. I still believe we should leave immediately."
Jommy Cross shook his head decisively. "I didn't let you see this in my mind before, but the main reason I don't want to leave here is that, until your face is disguised and your tendrils are hidden by false hair – a really difficult job – this is the safest place for both of us. Every highway is being watched by the police. Most of them know they're looking for a slan, and they have your picture. I turned off the main road in the hope of being able to find you before they did."
"Your machine goes up, doesn't it?" Kathleen asked.
Jommy Cross smiled mirthlessly. "Seven hours yet till dark; and every other minute we'd run into a plane. Imagine what the pilots would radio to the nearest military airport when they saw an automobile flying through the air. And if we go higher, say fifty miles, well surely be seen by a tendrilless slan patrol ship.
"The first commander will realize instantly who it is, report our position and attack. I've got the weapons to destroy him, but I won't be able to destroy the dozens of ships that follow – at least not before potent forces strike this car so hard that concussion alone will kill us. And besides, I cannot willfully put myself in a position where I may have to kill anybody. I've killed only three men in my life, and every day since then my reluctance to destroy human beings has grown until now it is one of the strongest forces in me – so strong that I have based my whole plan for finding the true slans on an analysis of that one dominant trait"
The girl's thought brushed his mind, light as a breath of air. "You have a plan for finding the true slans?" she questioned.
He nodded. "Yes. It's really very simple. All the true slans I have ever met – my father, my mother, myself, and now you – have been goodhearted, kindly people. This in spite of human hatred, human efforts to destroy us. I cannot believe that we four are exceptions; and therefore there must be some reasonable explanation of all the monstrous acts which true slans seem to be committing."
He smiled briefly. "It's probably presumptuous of me even to have a thought on the subject at my age and limited development. Anyway, I'm afraid it's been an utter failure so far. And I mustn't make a major move in the game until I've taken further defensive action against the tendrilless slans."
Kathleen's eyes were fixed on him. She nodded agreement "I can see too," she said, "why we must stay longer."
Queerly, he wished she hadn't brought up that subject again. For the barest moment (he hid the thought from her) he had a premonition of incredible danger. So incredible that logic brushed it aside. The vague backwash of it remained – made him say: "Just stay near the car and keep your mind alert. After all, we can spot a human being a quarter of a mile away even while we're sleeping,"
Oddly enough, it didn't sound the slightest bit reassuring.
At first Jommy Cross only dozed. He must have been partly awake for some minutes, because though his eyes were closed he was aware of her mind near him, and that she was reading one of his books. Once, so light was his sleep, the question came into his mind: