"Yes," said Hal, hearing his own voice hollow with excitement inside the helmet.
He obeyed. The wall before him - before each of them - was scored vertically and horizontally by earlier torch cuts; and its surface was a mosaic of different depths of rock, marking the planes where torch cuts had parted a surface chunk from the granite beneath. His eyes were on John.
John raised his torch to the wall, with its muzzle less than hand's length from the rock. A slim, golden pencil of visible light that was the guide for the cutting beam, which could not be seen, reached out and into the face of the stope before him - and a wave of heat that was like a body blow struck Hal, even through the protection of his suit, as the rock was vaporized in an incredibly thin section by the moving, invisible beam.
As he had grown more expert at mucking-out, there had been more and more occasions when Hal had been caught up with his own work and could simply stand for a moment and watch the torchers; and he had come to the conclusion that their work must be very easy compared to his own. In fact, he had puzzled over why it made sense to have two teams working alternate periods, when it would have seemed to have been more practical to simply work a single crew of six or seven men straight through the shift. He now discovered one reason why. The sudden heat blow from the outburst of hot gases from the vaporized rock was breathtaking, even inside the protective suit; and his first experience of it now explained why the torchers worked in spurts, cutting for a few minutes, then pausing, then cutting again.
It was some moments before he could manage to observe two more new things. One was the fact that John seemed to be cutting in a peculiar pattern that moved his torch about strangely on the face of rock before him, as if the areas to be cut were marked in some complicated sequence; and the other was that he shut his torch off each time before beginning to cut a new chunk. He had barely absorbed these facts when John stopped working abruptly; and simply stood, a mechanical-looking figure in his suit, facing the wall. Hal stared at him, not understanding, then became aware that the hiss and crackle of the torches to his right were also giving way to silence. He looked and saw that all the others of the current crew had stopped cutting, except the miner at the far end of the face. Then that man also shut his torch off.
Hal's glove twitched upward to knock back his helmet and give himself some air as he had seen the current crew do so many times. Then he realized that no one else had yet touched their helmets. He checked his movement and stood, gasping in the closed suit, watching John until John reached up and lifted back his own helmet. Hal imitated him and, looking around, taking deep breaths, saw the other torchers opening up as well.
For a few seconds, he breathed air that was only warm; then he saw John putting his helmet back on and followed suit. The torches took up their hiss and crackle again; and once more Hal watched and sweated under the momentary heat-blows before another helmetless break came. It seemed to last only seconds before they were buttoned up and at work again.
Before it came to be time for the other crew to replace them at the rock wall, Hal was soaked in sweat and as enervated as if he had worked a full half-shift at mucking-out, although he had done nothing but watch. But, as he became more accustomed to the heat-blows and the noise, his observation of the way the work went had been improving. He saw that a chunk would be carved out, wherever possible, by undercutting a projecting piece of rock; and then taking out as many other chunks as possible by cutting vertically down to the horizontal undercut. Where there was no way of undercutting, the torcher made slanting cuts into the face of the rock, until these intersected behind the chunk.
At the first touch of the cutting beam, there would be an explosion of gases from the vaporized rock; and for a moment the seeing was, not exactly foggy, but distorted; as if he was looking at the rock wall through the updrafts of heated gas and air. In the moment following the heat blow and the distortion, the view of the rock became solid again; but for a few seconds after that a sort of silver mist seemed to cling to the face of the rock, before vanishing.
It was not until the second time the crew including John and Hal attacked the wall that Hal put the sight of the silver mist together with the pattern of the torchers in knocking back their helmets. It was never until that haze had completely gone that any of them cracked their suits open. Hal's mind, galloping ahead with that observation, deduced that the silver mist must be condensation of some of the gasified rock, boiled out upon the surface of the face and chilled there by the liquified gas coolant projected around the cutting beam from its reservoir in the heavy body of the torch. Until the mist evaporated, there would be danger of some of the vaporized material being still in gas form, in the atmosphere before the stope wall.
As work wore on, Hal began to pick up more understanding of the pattern in which John was cutting into the rock face. The pattern seemed to be designed to keep him cutting always at the greatest possible distance from where the man on his right was cutting on his own section. Looking down along the face, Hal saw that the same patterning seemed to be at work to keep the others of the crew cutting at as close to maximum distance from each other as possible.
The lunch break finally came. John sat down to eat with his back to the tunnel wall beside Hal.
"Well," he said, tearing into a sandwich with his teeth, "how about it? You ready to try it?"
Hal nodded.
"If you think I can."
"Good," said John. "At least, you're not so all-fired sure you can just stand up there and do it. Now, I'll tell you what. Pay no attention to how fast the others are cutting. You cut only when I tell you to, and where I tell you to. Got that?"
"Yes," said Hal.
"All right." John finished his sandwich and got back to his feet. "Let's go, crew!"
He, Hal and the others returned to the face. Davies, who had taken over the mucking-out temporarily while Hal tried out with the torch, winked at Hal as Hal passed. Hal took the wink for encouragement and felt warmed by it.
At the face, guided by John's voice and pointing finger, Hal slowly began to choose and excavate pieces of the rock. He did not do well, in his own estimation. He found himself taking a dozen cuts to loosen a piece of rock that John might have taken out in three. But, gradually, as he worked, he began to get a little more efficient and economical in the use of the torch, although the patterns in which John directed his work remained beyond him.
As the shift wore toward its end the heat seemed to sap the strength out of him; it became enormous effort just to lift the torch and concentrate on the cuts John indicated he was to make. His cuts became clumsier; and, for the first time, he began to realize the danger of losing precise control of the torch, which, waved around carelessly in its on mode, could slice through suits, human flesh and bone with a great deal more ease than it could through rock - and the rock offered it no problem.
Through the window of his helmet as he continued cutting, he was aware of John watching him closely. John must know that exhaustion was making him uncertain; and at any minute now the team leader would be taking the torch away from him. Something in Hal surged in rebellion. At the next chance he had to knock back his helmet he deliberately drew a deep breath and let it out in slow, controlled fashion as he had been taught, both by Malachi and by Walter… and his mind smoothed out.
He had been letting himself become frantic because he could feel his strength dwindling. That was not the way he had been taught to handle situations like this. There were techniques for operating on only a remaining portion of his strength.