when lucy, that morning at badheim hospital, had remarked bob’s altered face, she blamed it all on his exposure to the snow-storm the afternoon before. she never guessed how he had spent the middle hours of the night following the visit to herr johann’s lodge, and bob, still undecided on his own course of action, had let her think that he was tired and moody because his leg hurt him.

it did hurt, as a fact, after his midnight adventure, for he had been on his feet longer than he realized, oblivious to pain in the absorption of his discovery. he did not know just what it was that started him up out of bed on his tour of exploration, except that in a troubled dream he had seen franz driving through the snow-storm, and herr johann looking on with his face of calm audacity. for some reason, or by a kind of warning instinct, bob had got up and dressed as eleven o’clock showed on the radium dial of his watch. he crept out of his room on to the hospital veranda, where all was darkness and silence.

in a moment he was crossing the open, the snow faintly lighted by a moon across which wind-clouds drifted. the air was very cold. he buttoned his overcoat as he entered the forest, and, walking fast, came in a quarter of an hour to the edge of franz’ clearing and heard the spring bubbling up in its basin somewhere on his left.

the little cottage showed dark against the snow, its shadow lying in front of it in the moonlight. bob leaned against a tree and watched a moment, shivering as the wind stirred the branches, and wondering if he were losing his sleep and freezing himself for nothing. he had not stood there five minutes when something moved in the shadow in front of the cottage. someone had come out of the door, closing it silently. the woodcutter paused at the edge of the moonlight and cast a quick glance about the clearing. then, putting his fingers to his mouth, he gave a shrill whistle.

at once another man appeared from the forest opposite to where bob stood watching. he crossed the snow at a hurried walk, with an awkward, stoop-shouldered gait. at his approach franz turned the corner of the cottage and the two disappeared behind it.

curiosity would not let bob stay where he was, yet to cross the clearing in the moonlight was to invite discovery. though the men were too busy to notice him he imagined trudchen’s unhappy, anxious eyes on guard at the darkened cottage window, ready to give warning of any intruder. but he determined to risk it, rather than wait in hiding and learn nothing. he fought against his impatience for ten or fifteen minutes, until the moon vanished behind a cloud and for a moment left the clearing in comparative darkness. then he made a run for it, and, when the cloud had glided past, he was in the shelter of the cottage walls.

he crouched down against the rough pine logs, stealing cautiously toward the rear. now he could hear sounds of the animals being led out and harnessed, and of a load of wood piled on the wagon. he heard no voices. the two men seemed not to exchange a word as they worked, as though eager haste left no time for a moment’s conversation.

bob reached the back corner of the cottage, and, peeping around it, saw the wagon standing, with the animals harnessed, in front of the shed. it was already half loaded with fagot-bundles, which franz and his companion were still carrying out on their backs from within the shed. in five minutes more the wagon was well loaded. franz muttered something to the other, upon which both of them left the shed and, going over to one of the fagot-piles in the clearing, brought bundles of wood from there to form the top layers of the load.

bob’s heart gave a thump of sudden comprehension. “it was from the top layer that larry and i took our bundle,” he thought, catching hold of the cottage wall to keep himself from bursting out and facing franz then and there.

a few minutes more and all was ready. the tarpaulin was lashed on the wagon and the shed doors closed. the two men mounted to the seat and drove slowly off across the snow toward the forest road.

bob made himself wait until the wagon had entered the woodland, then he ran to the shed doors, unbolted and flung them open. he drew out his torch and flashed it over a rough floor strewn with fagots, balls of string and bits of wood and bark. overhead was nothing but rafters, with a rack full of hay. on one side were the animals’ stalls.

he began examining the floor inch by inch. half-way through he left off to enter one of the stalls and there continue his scrutiny. he kicked aside a handful of straw and a crowbar lying at one side.

“here we are,” he said to himself.

setting his torch between the bars of the manger, he took up the crowbar and pried it into the cracks of the flooring. at the second trial a big piece of the floor—boards nailed together—rose up and tipped over, leaving a black, gaping hole. he seized the torch and played its beams over the opening. a ladder led downward half a dozen feet.

bob felt of the ladder, stepped on it, flashed his light ahead of him and descended. he found himself in a little cellar, chill with sunless cold, its walls piled with wooden boxes. on the floor were bundles of fagots, and piles of loose wood, ready to be tied. bob turned his light on the boxes, fumbled with the lids, found one on which the boards had been laid back unfastened, and pushed them aside.

“of course—might have known it,” he thought, a rush of anger mounting in him until he forgot the cold in a burning heat of indignation. the box was filled with machine gun ammunition belts. with his foot bob touched a rifle bullet lying on the floor. “good enough, herr johann, so you’re a bolshie after all. androvsky was right about the boches. they’ll take any means for an end.”

as bob made these bitter reflections he turned and remounted the ladder. he put back the piece of flooring, and scattered the straw about the stall again. switching off his torch he went slowly toward the shed doorway, outside of which stood trudchen in the moonlight, a ragged shawl gathered about her, her hair flying in the wind and her face set with terror.

bob looked at her with sharp annoyance. he was in a rage at franz and he wanted to hate everything belonging to him. so it was with real vexation that he found himself feeling not so much anger as pity at sight of the trembling woman before him. he thrust his torch into his pocket and said moodily:

“well, frau, do you stay up all night, too? franz has a nice little business here. i’ve been looking over his stores.”

he started off, but trudchen came beside him, panting, one hand touching his arm.

“herr captain, will you listen? will you have pity on us?” she entreated, her fluent german, in her breathless haste, almost too much for bob’s unaccustomed ears.

“listen to what?” he asked impatiently. “i know all about it.”

trudchen began to wring her hands in her desperation. “oh, herr captain, my children! what will become of us? franz has obeyed herr johann like a dumb slave! it was he who took us out of starving poverty, after we had to leave the reichsland. it was he who promised to support us if franz would—if he would——”

“take charge of the munitions stored here and get them safely over the river,” put in bob.

“but oh, herr american, franz did not want to! and i, god knows i did not want to have anything to do with it. but it was that or all starve together. franz persuaded me that he was serving germany, and that we would be rich and happy. in two weeks more it was all to finish, our shed would be empty and the danger over. i don’t half understand.”

“herr johann employed other men, too, didn’t he?”

“oh, yes, many. all along the rhine, north and south, where stores of munitions are hidden. from long ago, before the war ended, they are hidden. oh, what am i telling you!” in her misery and bewilderment poor trudchen buried her face in her ragged shawl and sobbed.

moved with pity, harden his heart as he would, bob touched her arm, saying, “don’t cry, frau. look here—we’ll help your children. it’s not their fault.”

“oh, kind herr captain, have pity on us! don’t betray franz to your officers!”

“not——” bob checked himself on the verge of an indignant retort. “we won’t forget your children, anyway. go back into the house now. what time will franz get home? tell me the truth. it will be best for him.”

“not before night, he said. oh, mein herr, what will happen to us?” trudchen shook her head as she tried to wipe the tears from her eyes. “it is hard to live poor and without hope. herr von eckhardt promised us wealth.”

“have you known him long?” asked bob.

“yes, many years, for franz was his game-keeper before the war. our little farm was on his estate in the reichsland. and during the war franz was his soldier-servant. oh, are you going away now? what are you going to do?”

“nothing, just now,” said bob, his forbearance at an end and longing only for solitude in which to think over what he had discovered. “good-bye, frau, and don’t despair.” he fairly ran away from the shed and across the clearing.

it was not an hour after midnight when he reentered the hospital, but he slept so little between then and daybreak that his tired face struck lucy with dismay when she saw him at breakfast time. he put her off with evasions, unwilling to confide in her just then, lest in her anxiety she should oppose his plan. he had risen with the dawn, found miller, the hospital corps man who had accompanied him and alan from archangel, and sent him into the forest on guard.

“i’ll have you excused here,” he told him. “go to the clearing every hour all day. if you see any men gathered there come back and tell my sister. say i told you to, and that she must notify headquarters in coblenz.”

he never guessed lucy’s own schemes nor her absence from the hospital, when, shortly after her departure, he obtained leave of absence to visit his father and drove to coblenz in general gordon’s car. he had the chauffeur drop him at larry’s lodgings and dismissed the car. but the lodgings were empty, for larry had that moment left in response to lucy’s call. bob decided there was no time to lose looking for his friend, or for general gordon either. he saw the pale, wintry sun already sinking, and knew that twilight was not far off. he must discover elizabeth’s rendezvous now if at all.

naturally he had no inkling of elizabeth’s agreement to cross the river to meet her husband. he knew no more than what the german woman had told him of her next meeting with franz, the day he had surprised her on the embankment. he followed, for want of a better plan, the same road by which he and larry had gone that day. walking fast, he came out before long by the river and began sauntering along one of the terraces, glancing about him for any sign of a familiar figure.

the silver ripples of the broad river shone in the late sunlight, and occasional boats glided along its current. there were promenaders on the embankment, but, though bob wandered along for a quarter of a mile, he saw nothing of either franz or elizabeth. yet he hated to give up the search. after having, the night before, wrested franz’ secret from him, he could not get over the feeling that to-day was to see the whole mystery revealed.

all at once, as he stood leaning for a moment against a tree and looking out over the river, he heard the sound of oars in row-locks below him, and, glancing down, saw a big rowboat, rowed by two men, with a barge in tow, loaded with wood. it passed slowly on up the river, bob’s eyes on it until it was a hundred feet away. at sight of the wood he had given a start. usual and commonplace as such a cargo was, it recalled all of last night’s revelation to him now. he looked at the rowers and recognized franz and the stoop-shouldered man who had met him at midnight in the clearing. at the rowboat’s stern was a little canvas shelter. bob tried to peer beneath it, but without success. was elizabeth crouching there? tensely he stood a second longer, watching. in that second he saw a french torpedo-boat bear down upon the wood-barge, and saw franz hoist the flag that was his permit to navigate the river with his cargo.

“fooled by that boche!” bob thought, anger rising again hotly in him. he turned and ran from the embankment.

his one thought now was to follow franz to his destination. but he had no motor-boat at his disposal, and to find one was not, like lucy’s, his first idea. another and a swifter means of travel occurred to him, as for two years back it had done in every predicament where there was distance to be covered. he met an army motor-car passing through the streets and, hailing the driver, asked to be taken to the air field.

airplanes were few in coblenz, but bob got hold of one, for the use of an airplane was a thing no one in the allied armies could refuse bob gordon. he gave the engine of the curtis biplane offered him the merest glance over. he knew the flight could be but a short one. he promised the frankly curious lieutenant in charge to return the plane that night and to tell him all about it. in half an hour after he had seen franz glide past the embankment, and about the time that larry sent his message to major harding, bob was up in the air and flying over the rhine.

he found glasses in the plane’s cockpit, and with them searched the river, flying at low speed about eight hundred feet above the water. it did not take him long to find the rowboat with the barge in tow. it was moving steadily on up-stream. he mounted higher and flew over the castle of ehrenbreitstein, in case the hovering plane should arouse franz’ suspicions. it was easy enough to keep the barge in sight on its slow progress. he floated about among the clouds until franz and his fellow-oarsmen turned in close below the hamlet of altheim.

bob watched them land, draw the barge in and moor it, after which franz’ companion began rowing on up-stream alone. but through his glasses bob had seen a woman’s figure step from the boat on to the landing-stage and follow franz up the hillside, almost running behind his big strides. sinking lower, bob saw franz and elizabeth turn from the hamlet road to climb the slope toward the lonely cottage, then he flew on over the hamlet to the pasture lands beyond.

twilight was falling, and bob’s last archangel flight had left him with no love for night landings on unknown ground. without more delay, he picked out a stretch of level meadow that made a high, narrow valley behind the hamlet. he flew slowly down and landed on the snow-covered grass.

lights had begun to twinkle from the near-by houses, and dusk had turned everything violet and grey around him. he caught sight of a boy’s dim figure crossing the field, and with a shout ran over to him.

“do you want to earn something guarding my airplane?” he asked the lad, who had stopped to stare at him. “can i trust you to let no one come near it?”

“ja, ja, herr officer,” consented the young german eagerly. “no one would dare when i tell them you are coming back.”

the bargain was soon struck and bob, skirting the silent hamlet, hurried at his best speed down the hill toward the landing-stage. it was deserted when he came in sight of it. darkness had fallen and the moon was shining. he saw the barge moored in the shadow of the birches.

“how do they expect to get away?” he wondered. then, with a start, he saw the outline of a motor-boat below the landing-stage, and a man sitting in it.

bob drew his revolver, stole on to the shaky planks of the stage and called out a challenge in german. the motor-boat’s occupant stood up uncertainly, bareheaded in the moonlight, and leaning toward bob with one hand on the landing-stage, said doubtfully:

“i don’t speak german, sir. ain’t there some mistake?”

“seems to be,” said bob, smiling in spite of himself. “who are you, anyway? whose boat is this?”

“it’s a government boat, sir. i’m the engineer. i brought captain eaton over from coblenz, and——”

“you did? where did he go?”

“he went up the hill there, toward that light you see near the top. they were after some——”

“who’s this?” said bob suddenly. as he spoke he sprang into the motor-boat beside rogers and crouched low, pulling the soldier down with him. a second motor-boat had glided into view, coming down the river, and, slowing speed as it turned toward the shore, it made for the bank with engine softly purring.

it drew near the landing-stage. bob peered over the gunwale, ready to challenge if it came closer. but the man at the wheel, leaning forward to look out into the moonlit darkness, no sooner caught sight of the other boat than he swung sharply inshore below the hamlet, a dozen yards from where bob awaited him.

bob now saw that the unknown craft held two men and that they were excitedly conferring together, while the unmoored boat tossed idly on the rippling water. then the steersman swung the boat’s nose around again.

“start your engine!” cried bob to rogers, who silently obeyed. it was plain that the stranger, at this unexpected intrusion, was going to run away without landing. bob seized the search-light beside the wheel, flashed it over the other boat’s bows, and saw von eckhardt, still disputing hotly with a scared-looking man whom bob recognized as franz’ companion, and who was turning the wheel rapidly from side to side ineffectually trying to get the boat into the stream.

“full speed ahead!” bob ordered. “cut that boat off before it gets a start. i’ll do the rest.”

rogers pushed off from the dock and ran his boat quickly up-stream to where the other still made little headway amid the steersman’s frantic shiftings of the wheel.

“now full speed astern, and hold her here a moment,” said bob.

almost alongside the other boat, which now began to gain momentum enough to slip away, bob drew his revolver and, firing two shots before her bows, called out, “herr von eckhardt, i am captain gordon. please put inshore. i wish to speak with you.”

von eckhardt’s body shook with rage, and his heavy lifted hand came down on the steersman’s head in a cruel blow. “dum kopf! stupid dolt that thou art!” he cried, shaking his fist in the man’s face. “if karl had been here!”

the words came clearly over the strip of water. at karl’s name bob started, the reason for elizabeth’s mysterious conduct all at once vaguely dawning on him.

“please step on board this boat, herr von eckhardt,” he directed. “your man can run inshore to wait.”

his words left no room for argument. von eckhardt saw the revolver gleaming in his hand, and turning his head, saw the search-lights of a french torpedo-boat steaming down the river. he attempted no defiance. as the two boats drifted alongside, rogers holding them a foot apart, von eckhardt sprang across and stepped down beside bob, his face pale and mask-like in the moonlight, except for his eyes glowing with sombre fire.

“of what am i accused, herr captain?” he flung at bob.

“i cannot tell you just now,” bob answered. “but perhaps i can satisfy you when i have seen the others, up in the cottage there.”

rogers had moored the boat once more at the landing-stage. bob saw von eckhardt’s eyes suddenly fixed on the loaded barge looming out of the shadows, though almost instantly he looked away.

“i’ll trouble you to hand over your arms, herr von eckhardt,” bob said.

von eckhardt slowly unbuttoned his overcoat and drew out a revolver.

“this is all you have?” bob asked, taking it.

“yes,” said the other, flashing his arrogant glance at the young american.

“engineer, take my revolver. it’s the regulation sort. guard this german until i come back. i am captain gordon.”

“yes, sir,” said the soldier, taking the revolver. “please sit down opposite me,” he directed von eckhardt, who silently complied.

bob glanced at the german, then spoke aside to the soldier, “don’t take your eyes off him. he’s a slippery customer. shoot if he tries to escape.”

rogers nodded agreement. without another thought, in his eagerness to rejoin larry and have all made clear, bob stepped ashore and ran up the hill toward the little house where, in another few moments, he and lucy surprised each other.

karl appeared dumbfounded at sight of bob, and his remaining braggadocio left him. he was all timid willingness to please and could not obey orders quickly enough.

“come, let’s get them to the boat,” proposed larry. “we were just starting when you came, bob.”

“all right. what about the old cottager? what’s to be done with him? dick, i have a thousand things to ask and tell you,” said bob, slapping major harding’s shoulder. “when did you get here, and how did larry know——”

“that elizabeth was to cross the river? it was lucy’s doing. i got to coblenz early this morning. as for the old boche,” nodding toward the owner of the cottage, who stood staring fearfully from one officer to the other, “let’s leave him alone. he’s just a wretched tool in their hands.”

“and they are tools in von eckhardt’s hands,” said bob. “it’s hard to know who to blame.”

“come, elizabeth,” said lucy, taking her old nurse’s arm. “i’ll go with you. don’t be afraid.”

“is that steersman of yours a reliable sort of fellow, larry?” asked bob. “i’d hate to have von eckhardt give him the slip.”

“oh, rogers is all right.”

they had come out into the moonlight and begun to descend the slope, karl and franz guarded by ed and larry. almost as larry spoke a shot rang out from below the hill.

in the hush of alarm bob gave a sudden cry. “fool that i am! i forgot the other man, karl’s helper in von eckhardt’s boat! come, harding!”

he plunged down the steep path, major harding at his heels, and in five minutes reached the riverside.

rogers and von eckhardt were still in the motor-boat, but rogers was leaning over the side, a smoking pistol in his hand. von eckhardt was shouting orders across a dozen feet of water to his own boat, which, navigated by the pilot’s clumsy assistant, was getting under way, towing after it the loaded barge, unloosed from its moorings.

“jump in, dick! hurry! we must turn back that boat!” cried bob with mounting excitement.

he jumped in beside rogers and von eckhardt, followed by major harding. “start her up! get in front of that fellow and head him off!” bob panted.

rogers handed him the pistol and sprang to the engine. von eckhardt, stopping his frenzied directions, stood motionless, watching his boat, which had now got into the current and was making fair speed up-stream, the barge in tow.

rogers pushed off and rapidly gave chase. the race was lost for the german boat from the beginning. von eckhardt sank down on the seat and sat staring at the floor.

while the boat overtook its quarry rogers gave a hurried account of what had happened.

“you told me to shoot, sir, so when this fellow here began shouting out to his friend and telling him, as i made out by his gestures mostly, to come over and untie the barge and tow it off, i threatened to fire. but he defied me and said, 'shoot away.’ i couldn’t just make up my mind to shoot him down like that, so instead i began firing at the other boat, hoping to cripple it. in the moonlight my shots went rather wild. i think i hit the other german. he cried out——”

“yes, looks as though you had,” said major harding, pointing to the german pilot, who, steering with one hand, held the other pressed against his right shoulder.

“easy now,” said bob to rogers. “cut across his bows. von eckhardt,”—he turned toward the german who sat with bent head in the boat’s stern—“tell your man to run inshore, will you? or do you want us to shoot him?”

von eckhardt raised his head and in a dull, stifled voice called out the order. the german craft slowed and swung around, pointing downstream again, the barge slewing about in its wake. ten minutes more and both motor-boats were back at the landing-stage below the hamlet, where larry, ed, franz, karl, lucy and elizabeth stood waiting.

as major harding stepped ashore he said, “bob, i’ve talked this over with eaton, but not with you. are you on to these fellows? do you know that von eckhardt has been smuggling arms and munitions along the rhine to the bolsheviki in germany and elsewhere? we’re not sure of the details yet, nor of how the stuff is carried, though eaton thinks——”

“he thinks right,” said bob, glancing toward the barge. “karl, bring one of those fagot-bundles—one of the real ones.”

karl sprang forward, once more the obedient servant, eager to conciliate the man who had got the best of him. he boarded the barge and in a moment returned, carrying a bundle of fagots which he laid carefully down on the landing-stage. larry turned the motor-boat’s search-light on the bundle as karl cut the fastenings. the wood fell apart, revealing a neat package of machine gun belts, wrapped in water-proofed cloth.

karl looked up at bob, almost as triumphantly as though he himself had disclosed the conspiracy. franz stood sullenly apart. the americans’ eyes were turned on von eckhardt, who still sat motionless, not having once raised his head.

hot with anger and lingering amazement, larry addressed the german in scornful questioning, “why, von eckhardt, i thought you despised the spartacan rebels and their bolshevik friends. why should you wish to help them? i thought you were a prussian of the old régime!”

the german stood up in the boat, folded his arms and answered with frozen calm: “you are right, captain. i despise the spartacan rebels. but they would have been my tool with which to overthrow the republican government—already tottering. i sought to bring back imperial germany—vain hope!”

“yes, vain enough,” said major harding. he spoke almost solemnly. “von eckhardt, your schemes will be unknown to history, and yet i wonder if peace has not been saved by their discovery.”

lucy listened, stirred with awe and astonishment. knowing no more of von eckhardt’s plots than the part in which franz had shared, she could not yet understand major harding’s earnestness. elizabeth, sunk in uncomprehending misery, was crying softly by her side. between sobs she whispered:

“miss lucy, what will they do to karl? oh, better i never asked him to come here!”

the little german woman still thought that her husband had come on purpose to see her.

“i must go for my airplane,” said bob. “karl can run von eckhardt’s boat to coblenz and tow the barge.” in answer to a doubtful look from larry he added reassuringly, “oh, karl is as trustworthy now as you or i. don’t you see, he’s with us again? he’s always on the winning side.”

larry was tying up the wounded shoulder of the german whom rogers had shot. lucy bent to help him and, in the man’s broad head and heavy, stooping figure, recognized the lodge-keeper called ludwig, whom she and michelle had seen at midnight in the forest. she saw the man look up to cast a glance of bitter hatred at von eckhardt.

“we won’t have much trouble getting the truth out of this chap,” said larry with a chuckle. “doesn’t seem fond of his noble master.”

lucy took opportunity to whisper, “don’t be hard on elizabeth, larry. don’t treat her like the rest.”

larry nodded. “bob’s gone already,” he said, looking behind him. “let’s beat him to coblenz.”