Now the 'touching off' of a good-sized mine is not a matter to be done lightly or without due and weighty authority, and that because more is meant to result from it than the upheaval of some square yards of earth and the destruction of so many yards of enemy trench. The mine itself, elaborate and labour-making as it may have been, is, after all, only a means to an end. That end may be the capture of a portion of the ruins of the trench, it may be the destruction of an especially strong and dangerous 'keep,' a point of resistance or an angle for attack. It may even be a mine to destroy a mine which is known to be tunnelling into our own trenches, but in any case the explosion is usually a signal for attack from one side or the other, and therefore requires all the usual elaborate arrangements of reinforcements and supports and so on. Therefore the Sapper Subaltern, when he had finished his work and made his report, had nothing to do but sit down and wait until other people's preparations were made, and he received orders to complete his work by utterly and devastatingly destroying it. The Subaltern found this wait about the most trying part of the whole affair, more especially since he had for a good many days and nights had so much to occupy his every moment.
He received word at last of the day and hour appointed for the explosion, and had the honour of a visit of inspection from a very superior officer who pored long and painstakingly over the paper plans, put a great many questions, even went the length of walking down the communication trench and peering down the entrance shaft, and looking over the sandbagged wall through a periscope at the section of German trench marked down for destruction. Then he complimented the Subaltern on his work, declined once again the offer of a muddy mackintosh and an invitation to crawl down the mine, and went off. The Subaltern saw him off the premises, returned to the shaft and donned the mackintosh, and crawled off up his tunnel once more.
Somehow, now that the whole thing was finished and ready, he felt a pang of reluctance to destroy it and so fulfil its destiny. As he crawled along, he noted each little bit of shoring-up and supporting planks, each rise and fall in the floor, each twist and angle in the direction, and recalled the infinite labour of certain sections, his glows of satisfaction at the speed of progress at the easy bits, his impatience at the slow and difficult portions. It seemed as if he had been building that tunnel for half a lifetime, had hardly ever done anything else but build it or think about building it. And now, to-morrow it was all to be destroyed. He recalled with a thrill of boyish pleasure the word of praise from the Corporal—a far greater pleasure, by the way, than he had derived from the Great One's compliments—the praise of one artist to another, the recognition of good work done, by one who himself had helped in many good works and knew well of what he spoke. 'She's done, sir,' the Corporal had said. 'And if I may say so, sir, she's a credit to you. A mighty tricky job, sir, and I've seen plenty with long years in the Service that would ha' been stumped at times. I'm glad to have had a hand in it wi' you, sir. And all the men feel the same way about it.'
Ah well, the Subaltern thought as he halted at the joint of the T-piece, none of them felt the same about it as he himself did. He squatted there a moment, listening to the drip of water that was the only sound. Suddenly his heart leapt . . . was it the only sound? What was that other, if it could be called a sound? It was a sense rather, an indefinable blending of senses of hearing and feel and touch—a faint, barely perceptible 'thump, thump,' like the beat of a man's heart in his breast. He snapped off the light of his electric lamp and crouched breathless in the darkness, straining his ears to hear. He was soon satisfied. He had not lived these days past with the sound of digging in his ears by day and his dreams by night not to recognise the blows of a pick. There . . . they had stopped now; and in imagination he pictured the digger laying down the pick to shovel out the loosened earth. Then, after a pause, the measured thump, thump went on again. The Subaltern crawled along first one arm of the cross-section and then the other, halting every now and then to place his ear to the wet planking or the wetter earth. He located at last the point nearest to the sound, and without more waste of time scurried off down his tunnel to daylight.
He was back in the mine again in less than half an hour—a bare thirty minutes, but each minute close packed with concentrated essence of thought and action.
The nearest trench telephone had put him in touch with Battalion Headquarters, and through them with Brigade, Divisional, and General Headquarters. He had told his story and asked for his orders clearly, quickly, and concisely. The Germans were countermining. Their tunnel could not possibly miss ours, and, by the sound, would break through in thirty to sixty minutes. What were his orders? It took some little time for the orders to come, mainly because—although he knew nothing of it—his mine was part of a scheme for a general attack, and general attacks are affairs that cannot be postponed or expedited as easily as a cold lunch. But the Subaltern filled in the time of waiting, and when the orders did come he was ready for them or any other. They were clear and crisp—he was to fire the mine, but only at the latest possible minute. That was all he got, and indeed all he wanted; and, since they did not concern him, there is no need here to tell of the swirl of other orders that buzzed and ticked and talked by field telegraph and telephone for miles up and down and behind the British line.
Before these orders had begun to take shape or coherency as a whole, the Subaltern was back listening to the thump, thump of the German picks, and busily completing his preparations. It was near noon, and perhaps the workers would stop for a meal, which would give another hour for troops to be pushed up or whatever else the Generals wanted time for. It might even be that a fall of their roof, an extra inflow of water to their working, any one of the scores of troubles that hamper and hinder underground mining might stop the crawling advance of the German sappers for a day or two and allow the Subaltern's mine to play its appointed part at the appointed time of the grand attack.
But meantime the Subaltern took no chances. First he connected up a short switch which in the last extreme of haste would allow him with one touch of his finger to blow up his mine and himself with it. He buried or concealed the wires connecting the linked charges with the switch outside so as to have a chance of escape himself. He opened a portable telephone he had carried with him and joined up to the wire he had also carried in, and so was in touch with his Corporal and the world of the aboveground. All these things he did himself because there was no need to risk more than one man in case of a quick explosion. Then, his preparations complete, he sat down to wait and to listen to the thudding picks of the Germans. They were very near now, and with his ear to the wall the Subaltern could hear the shovels now as well as the picks. He shut his lamp off after a last look at his switch, his revolver, and the glistening walls and mud-ooze floor of his tunnel, and sat still in the darkness. Once he whispered an answer into the telephone to his Corporal, and once he flicked his lamp on an instant to glance at the watch on his wrist. Then he crouched still and silent again. The thumping of his heart nearly drowned the thud of the picks, he was shivering with excitement, and his mouth grew dry and leathery. He felt a desire to smoke, and had his case out and a cigarette in his lips when it occurred to him that, when the Germans broke through, the smell of the smoke would tell them instantly that they were in an occupied working. He counted on a certain amount of delay and doubt on their part when their picks first pierced his wall, and he counted on that pause again to give him time to escape. So he put the cigarette away, and immediately was overwhelmed with a craving for it. He fought it for five minutes that felt like five hours, and felt his desire grow tenfold with each minute. It nearly drove him to doing what all the risk, all the discomfort of his cramped position, all the danger, had not done—to creep out and fire the mine without waiting for that last instant when the picks would break through. It could make little difference, he argued to himself, in the movements of those above. What could five minutes more, or ten, or even fifteen, matter now? It might even be that he was endangering the success of the explosion by waiting, and it was perhaps wiser to crawl out at once and fire the mine—and he could safely light a cigarette then as soon as he was round the corner of the T. So he argued the matter out, fingering his cigarette-case and longing for the taste of the tobacco, and yet knowing in his inmost heart that he would not move, despite his arguments, until the first pick came through. He heard the strokes draw nearer and nearer, and now he held his breath and strained his eyes as each one was delivered. The instant he had waited for came in exactly the fashion he had expected—a thud, a thread of yellow light piercing the black dark, a grunt of surprise from the pick-wielder at the lack of resistance to his stroke. All this was just what he had expected, had known would happen. The next stroke would show the digger that he was entering some hole. Then there would be cautious investigation, the sending back word to an officer, the slow and careful enlargement of the opening. And before that moment came the Subaltern would be down his tunnel, and outside, and pressing the switch . . .
But his programme worked out no further than that first instant and that first gleam of light. He saw the gleam widen suddenly as the pick was withdrawn, heard another quick blow, saw the round spot of light run out in little cracks and one wide rift, and suddenly the wall fell in, and he was staring straight into the German gallery, with a dark figure silhouetted clear down to the waist against the light of an electric bulb-lamp which hung from the gallery roof. For an instant the Subaltern's blood froze. The figure of the German was only separated from him by a bare three yards, and to his dark-blinded eyes it seemed that he himself was standing in plain view in a brilliant blaze of light. Actually he was in almost complete darkness. The single light in the German gallery hardly penetrated through the gloom of his own tunnel, and what little did showed nothing to the eyes of the German, used to the lamp-light and staring suddenly into the black rift before him. But the German called out to some one behind him, twisted round, moved, stooping, back to the lamp and reached up a hand to it. The Subaltern backed away hastily, his eyes fixed on the glow of light in the opening. The hole had broken through on a curve of his tunnel, so that for fifteen or twenty feet back he could still see down the German gallery, could watch the man unhook the lamp and carry it back to the opening, thrust the lamp before him and lean in over the crumbling heap of earth his pick had brought down. The Subaltern stopped and drew a gasping breath and held it. Discovery was a matter of seconds now. He had left his firing switch, but he still carried the portable telephone slung from his shoulder, the earth-pin dangling from it. He had only to thrust the pin into the mud and he was connected up with the Corporal at the outside switch, had only to shout one word, 'Fire!'—and it would all be over. Quickly but noiselessly he put his hand down to catch up the wire with the earth-pin. His hand touched the revolver-butt in his holster, checked at it, closed round it and slid it softly out. All this had taken an instant of time, and as he raised his weapon he saw the German still staring hard under the upheld lamp into the gloom. He was looking the other way, and the Subaltern levelled the heavy revolver and paused. The sights stood out clear and black against the figure standing in the glow of light—a perfect and unmissable target. The man was bareheaded, and wore a mud-stained blue shirt with sleeves cut off above the elbow. The Subaltern moved the notched sights from under the armpit of the raised arm that held up the light, and steadied them on the round of the ear that stood out clear against the close-cropped black hair. He heard a guttural exclamation of wonder, saw the head come slowly round until the circle of the ear foreshortened and moved past his sights, and they were centred straight between the staring eyes. His finger contracted on the trigger, but a sudden qualm stayed him. It wasn't fair, it wasn't sporting, it was too like shooting a sitting hare. And the man hadn't seen him even yet. Man? This was no man; a lad rather, a youth, a mere boy, with childish wondering eyes, a smooth oval chin, the mouth of a pretty girl. The Subaltern had a school-boy brother hardly younger than this boy; and a quick vision rose of a German mother and sisters—no, he couldn't shoot; it would be murder; it—and then a quick start, an upward movement of the lamp, a sharp question, told him the boy had seen. The Subaltern spoke softly in fairly good German. 'Run away, my boy. In an instant my mine will explode.'
'Who is it? Who is there?' gasped the boy.