"Some Revelations of Spies and Spying" (continued 3)

I learned from Captain Jackson that Humber had signed on some months before, and had made a number of trips across the North Sea. He had been in the habit of travelling to London each time the vessel reached Newcastle, and at length this fact had aroused Captain Jackson’s suspicions, and he had made up his mind that this trip should be Humber’s last. It was, indeed, but the end came in a manner which not even Captain Jackson’s keen wits had anticipated.

In the meantime I knew that Aubert, a splendid linguist, who could play many parts, from that of an idler in Paris to a worker in a munition factory, was somewhere below in the engine-room, certainly not very far from Humber, and assuredly very much on the alert.

An hour after we left the Tyne mouth I was standing with some of the passengers on deck, watching some winking signals as our convoy appeared out of the misty twilight. Of what the convoy consisted I could not quite discern, but the Captain, before he ascended to his bridge, had said: “Our friends will pick us up presently, and they will see us safely across and look out for submarines.”

The night passed without incident, and the next day proved grey and windy. Ever and anon one of our patrolling airships paid us a visit, while three other ships, forming our convoy, stood by, with their deadly guns ever ready to talk in deadly earnest with any submarine that might venture to show her periscope.

At ten o’clock that night I was on deck watching a series of strange flashes of light showing in the eastern sky, when a sailor approached, and informed me that the Captain wanted to see me in his cabin. I went at once.

“Look here, Mr Sant!” the bluff old seaman exclaimed as soon as I had closed the door, which he locked. “I’ve been rummaging the ship. Does this interest you?” And he brought out from the drawer in his table a bottle of medicine. It had apparently been recently bought from a chemist, for it was wrapped up in the usual paper, which was still quite clean and fresh, and sealed in the usual way. “This was found by your French friend concealed in Humber’s trunk. Your man would be up here, only he is watching the fellow below, and as he is supposed to be on duty his absence might rouse suspicions.”

As Captain Jackson ended he handed me the bottle.

“It does interest me, indeed,” I said. “If Humber were ill enough to need medicine—and he certainly does not look it—he would hardly have brought this all the way from London without opening it.” And I thought of the bottle wrapped in white paper which, on an earlier visit to London, Humber had received from Blind Heinrich at Waterloo.

“I’ll have a look at it, anyhow,” I said.

My first precaution was to soften the sealing wax with a match, so that I could unwrap the bottle without tearing the paper, and, if necessary, so replace it that no suspicion that it had been tampered with should be aroused. The bottle might prove useless as a clue. In that case we should have to seek further, and to replace the bottle in Humber’s trunk in such a condition that he must inevitably see that it had been opened would certainly arouse his suspicions and defeat our object.

I soon had the paper opened out. The bottle of medicine seemed genuine enough. It bore the label of a well-known West End firm and the name of Mr Humber. I tasted the contents.

“Cough mixture” was my comment, and Captain Jackson at once confirmed me. “Humber never had a cough,” he remarked reflectively.

“Now for the paper,” I said, and began examining it. It was perfectly blank, and I was experiencing a pang of disappointment when, catching on the paper the reflection of the swinging lamp, I detected in one corner a faint, glistening line. Lemon juice, I was confident.

Under appropriate “treatment” a number of neat figures arranged in groups of three sprang into vivid prominence on the inside of the paper wrapping. They ran:

123—5—8; 27—32—6; 46—23—11; 294—12—3; 18—1—8; and so on.

I swiftly copied out the figures for safety, and handed the original paper to Captain Jackson, who, on board his own ship, was, of course, the supreme and unquestioned authority, and I wanted his full approval and support to any action that might be necessary. The figures were meaningless as they stood, but I had not forgotten old Heinrich’s systematic search for that odd volume of Royal Love Letters. I had my copy in my bag and fetched it at once.

With such an obscure book as the key to the cipher there was no need for any further elaborate precautions, and we hit upon the solution of the difficulty at once. On page 123 the eighth letter on the fifth line was “B;” on page 27 the sixth letter in the thirty-second line was “r”; and in a few minutes I had decoded the word “Brixton.” Going on, I found that the message conveyed the news that Number 24, — Road, Brixton, had been wrecked by one of the bombs dropped in the recent raid; that a man, a woman, and two children had been killed. The spots where the other bombs had fallen were accurately described, and it was stated that they had done no damage beyond blowing holes in the roads and bursting gas and water mains. Every word was accurate.

And the key to the whole problem was the mysterious advertisement for a lost trinket in the Petit Parisien. That simple advertisement, so apparently innocent, had announced to Blind Heinrich the enemy’s change of code! And without the book to which it referred no intelligence on earth could have deciphered the disorderly mass of figures which lay before our eyes!

“Well, I think we have got them now, Captain,” I said, “and I am sure the Government will be deeply obliged to you for your assistance. But how am I going to get this fellow? If he lands in Norway he will be out of our power.”

“Come on deck,” said Captain Jackson, with a laugh. “Don’t make your mind uneasy about that.”

I followed him up the companion-way ladder to the deck, now deserted by all save the steersman and the officer on watch.

“Come up to the bridge with me,” said the Captain.

Although it was so near the period of full moon the night was dark, the sky being covered by a dense mass of heavy clouds. Try as we would, our eyes could not pierce the gloom, and we could see nothing a few yards from the ship. Though we had parted company from the destroyers long before, we were, of course, travelling without lights in view of possible danger, and only the binnacle lamp shed a soft radiance on the ship’s compass. I was soon to learn, however, how closely we were watched.

Captain Jackson entered the wheel-house and touched a key. From the masthead above a signal lamp flashed intermittently for a few seconds. Instantly from the southward winked an answering gleam, and Captain Jackson turned to me. “That’s a destroyer,” he said, “and she is coming up full speed.”

For the next few minutes signals were exchanged with the racing destroyer which was on our track, and soon I caught sight of the faint glow from her funnels, and then the outline of her low, rakish hull as she came abreast with us. At a signal from Captain Jackson our engines stopped, and soon we were lying motionless while a boat from the destroyer pulled rapidly across the gap which separated the two vessels.

A few minutes later a smart naval officer came on board with four men. We were soon seated in the Captain’s cabin, and I rapidly gave him an outline of what had happened. His quick intelligence took in the situation at a glance.

“I’ll take your Mr Humber back with me,” he said, “and you and your man can come along.”

But we were nearly to lose our man. As the officer and his men entered the engine-room Humber caught sight of them. He started, but instantly recovered himself. As the lieutenant spoke to Phail, Humber watched him closely. I saw Aubert move noiselessly but swiftly behind Humber, evidently ready for a tussle. A moment later Phail beckoned Humber to come to him.

Instantly the spy’s hand shot to his jacket pocket, and, as it came out, bringing with it a revolver, Aubert sprang. The next instant the revolver was on the floor and Aubert had Humber in a grip of iron. Ten minutes later, with Humber securely handcuffed, we were on our way to the destroyer, and were soon thrashing our way at top speed for home.

There is little more to tell. Humber proved to be a Swede named Holmboë, and we clearly established the fact that he had been for a long time acting as the travelling agent of the Berlin espionage bureau, carrying information to Norway for transmission through the German Legation in Christiania. The conspirators in the house in Harrington Street were all taken into custody, and we soon had all the threads of their activities in our possession, including the key to the mystery of Mr Mostyn Brown, whose connection with various little affairs of espionage was clearly established. Blind Heinrich, too, was at length effectively unmasked, and, with the rest of the group, is now safely under lock and key, with ample leisure to repent of the nefarious business upon which they were engaged.

On this occasion, at any rate, the secret message failed to reach Berlin, and I often laugh when I think of the amazement and anxiety that must have been caused in the enemy’s camp at the sudden silence of their emissaries. To-day we can afford to make them a present of the truth!

Chapter Fourteen.

The Great Submarine Plot.

To be a success as a secret agent a wide knowledge of European hotels is an absolute necessity.

You must, indeed, be familiar with the best hotel in every city of any importance, and scarcely less important is the personal acquaintance of the manager; for without his help you will inevitably find in your path a thousand difficulties, small and great, which, with his friendly assistance, melt almost insensibly away. Duty and inclination alike have led me to make a special study of hotel life, and I think I may say, without undue egotism, that there are few maîtres d’hôtel in Europe with whom I am not on terms of acquaintance, and even in many cases warm friendship.

I was especially fortunate in this respect in the situation in which I found myself one sunny morning in June, 1917. As the clock struck ten I strolled out of a big hotel, which I will call the Waldesruhe, in Lucerne, and wandered along the shady avenue beside the lake in the direction of the Schwanen-Platz.

Luigi Battini, the manager of the Waldesruhe, was one of my closest personal friends, and I should have stayed at the Waldesruhe at any time I was in Lucerne quite apart from the particular business which had brought me there on this occasion. Luigi was one of those marvellously efficient human machines which appear almost to reach omniscience in everything connected, even remotely, with his profession. He would give his guests, off hand and without the slightest hesitation, minutely detailed directions for the most complicated of journeys without opening a time-table, and invariably his information was correct to the smallest particular. He knew at what stations every dining-car was put on every train within a radius of hundreds of miles, and he impressed upon you, in the far-off pre-war days, to remember that the train left Weis for Passau twenty minutes earlier this month than the hour mentioned in the time-table.

His memory, especially for faces, was prodigious. Indeed, it was to this that I owed the beginnings of our friendship. Years before Luigi had been a waiter at the great buffet at Liverpool where passengers from the incoming American boats were in the habit of snatching a hasty meal before joining the train for London. I had arrived in England from New York cold and hungry, and, owing to some delay about my baggage, was unable to get to the restaurant until just before the London express was due to start.

I had not realised how long I had been delayed, and had just taken my first mouthful of the soup which Luigi had brought me when the bell heralding the immediate departure of the train rang loudly. With a muttered ejaculation of annoyance I hastily threw down on the table the price of my abandoned meal and rushed out, jumped into the train, and a moment later was speeding Londonwards, still cold and hungry and in the very worst of tempers.

Of course I promptly forgot the incident, and it was not until a year later that I was forcibly reminded of it. I had again arrived in Liverpool from New York and hurried to the same restaurant for a meal. By some queer chance I made for a table at which Luigi was still the waiter. I should not have known him, but he recollected me and our previous meeting.

With a profound bow and a smiling flash of his exquisite teeth, Luigi said quizzically: “Good evening, monsieur. Has monsieur returned for his dinner?”

I looked at him in blank astonishment for a moment, then burst into a roar of laughter, as I remembered both him and the long-forgotten incident of a year before. The ice was effectually broken between us, and when I left for London I felt I had made a friend of the smiling Italian. But it was years before I discovered how deep and loyal a mutual regard had sprung out of a trifling incident. But the best friendships not infrequently owe their origin to some such triviality.

Time had slipped by since then, and Luigi had climbed the ladder until the humble waiter was a power in the great cosmopolitan world of the hotel. But to me, at any rate, he was the Luigi of old; to others he might be merely the official head of a perfectly appointed hotel, where arrangements seemed to go by clockwork and no one ever heard of such a thing as failure. Always in a frock-coat, whatever the season, whatever the hour of the day; always wearing the diamond pin given him by a travelling monarch; always alert though never obtrusive; known to all his guests, but familiar with hardly any—such was Luigi Battini. And he was one of Hecq’s “friends.”

I had gone to Lucerne on purpose to learn something from his lips which he would not risk in the post, and what he had told me half an hour earlier had set me thinking deeply. It entirely confirmed certain information I had been able to gain in London and Lisbon.

After a long and meditative walk, I seated myself on the terrasse of a café overlooking the lovely Lake of Lucerne, and, with a bock before me, wrote out a telegram as follows:

“Arthon, Paris.—Returning London fourteenth.—Casentino.”

Having finished my bock, I strolled along to the chief telegraph office near the station and dispatched the message. To the uninitiated it conveyed no other meaning than appeared on the surface, but its receipt at the address for which it was destined set various elements of machinery in motion.

On the evening of the fourteenth there stepped from the hotel omnibus—a smartly dressed young Frenchwoman, carrying a little sable Pomeranian dog and followed by a porter with her luggage.

Luigi met her in the hall, and, with his heels clicked together in his usual attitude of welcome, received her with an exquisite bow. She engaged a room, signed the visitors’ book in the usual way, and then allowed Battini to conduct her up by the lift. As she passed me our eyes met, but without the slightest sign of recognition. Even though the newly arrived guest was none other than my smartest assistant, Madame Gabrielle Soyez.

Next day, in consequence of a note I sent her, we met in one of the sitting-rooms in the further, and at the present moment unoccupied—wing of the hotel. She then told me that her own sitting-room was next to one occupied by a Swedish engineer named Oscar Engström, whom I had watched in Lisbon a month before and who was now in Switzerland engaged on some mysterious business which we had not been able to fathom. We strongly suspected, however, from various bits of evidence that had reached us, that the man was in the pay of Germany at the moment, even if he were not one of the regular German agents.

When I entered, Madame Gabrielle, smartly attired in a tailor-made gown of navy-blue cloth and a very bewitching hat, was standing at the window, with her pet dog beneath her arm, chatting to the immaculate Luigi, gazing the while on the blue waters of the lake.

I found myself reflecting how typically French she was in every detail—dainty in face and figure, immaculately dressed, and possessing that indefinably vivacious great charm which seems to be the monopoly of the cultured Frenchwoman. She could throw it aside when she chose, such was her wonderful versatility, and assume a mask of dullness and stupidity sufficient to ensure that no one meeting her would give her a second glance. It was a valuable accomplishment, and more than once had carried her safely through a difficult and dangerous situation.

To-day, among friends, she was her own sunny self. “Ah, Monsieur Gerald,” she cried, springing forward to greet me, “our friend Luigi has been telling me some very strange things—eh?”

“I have told Madame pretty well all I know,” said the suave Italian, in excellent English; “but it is not much. Engström has engaged a room for a lady friend—a Madame Bohman.”

“Swedish also?” I queried, with a smile. “When does our friend expect Mr Thornton, as he calls himself?”

“He is expected any moment,” replied Luigi; “he has retained his room ever since he left for London.”

“Good!” I said. And we all three sat down and plunged into an intricate discussion of every detail concerning the suspects and our plan of campaign.

My instructions to Luigi were to keep a constant watch upon the comings and goings of the Swedish engineer and his lady friend, while to Madame Gabrielle fell the task of endeavouring to scrape acquaintance with the latter on her arrival, in order to try to gain from some casual remark—for we could expect nothing more—a hint of what was in progress.

Engström’s lady friend, Madame Bohman, arrived in due course, and, though she was quite unaware of it, we scrutinised her closely before we gave her a chance of seeing us. I saw at once that she was a complete stranger to me. Madame Gabrielle did not know her, and Luigi, with his faultless memory for faces, declared positively that she had never entered any hotel at which he had been engaged.

“A new hand, in all probability,” I thought, “but none the less dangerous on that ground if she knows her business.” Madame Bohman was a tall, handsome, fair-haired woman of decidedly distinguished appearance, and, from the scraps of her conversation which we overheard, evidently well educated and well connected. She had the blue eyes and fair hair of the typical Swede, but blue eyes and fair hair are not exactly unknown in Germany, and, though there was no ostensible reason for it, I found myself wondering whether she was exactly what she professed to be. But the German spy bureau works with any tools that come handy, and, even though Madame Bohman were the pure-blooded Swede she professed to be, there was still no reason why she should not be an enemy agent as well. More than one Swedish “neutral” has been detected in that category and paid the penalty!

Chapter Fifteen.

The Real Mr Engström.

Three days after Madame Bohman’s arrival, a special messenger brought me from Hecq in Paris three reports which, when I had read them, reduced me to a condition of blank despair.

The first was from the French Consul-General at Stockholm, who had been instructed to make the closest possible inquiry into the bona fides of the shipbuilding and engineering firm of Engström and Linner, of Malmö. His report stated that he had paid a visit to Malmö, and as the result of his investigations there and elsewhere he had not the least doubt that they were a first-class firm, and it was a fact of considerable interest that they were employed by the Swedish Government upon several important contracts. No reason whatever could be suggested for doubting their sterling integrity, and the partners had never shown the slightest trace of pro-German bias, either as a firm or individually. This seemed a complete check to our suspicions.

The second report was from Aubert, whom I had left in Lisbon. Dated from the Palace Hotel, it read:

“I have kept constant observation upon the individual, Mr Thornton, but, with the exception of the fact that he is acquainted with Halbmayr, of the Königgrätzer-strasse—which, after all, may be quite innocent—I see no reason to suspect him of hostile intent. He has telegraphed several times to Lucerne, addressing his messages to the name of Syberg at the poste restante. You could probably secure sight of one of these; I cannot at this end. He was visited a fortnight ago by a Swedish lady named Bohman. The latter may be a travelling agent of the enemy, but somehow, after a close vigilance, I feel doubtful. When Thornton leaves I shall advise you. It will be best for Garcia to follow, as they have not met, and he is here for that purpose.”

The third report was from a certain very alert English business man named Charles Johnson-Meads, who had offices in Fenchurch Street, London. It was Johnson-Meads who, by a curious statement he made to me one evening, in my rooms in Curzon Street, London, had first aroused my suspicions that a deep plot, in which Engström and Thornton were somehow implicated, was on foot.

Johnson-Meads’ report read:

“I have strained every effort to learn more of these people and their mysterious movements in London. Contrary to my belief, I have now established the fact that Engström is, after all, the well-known Swedish engineer, and not the fraud I believed him to be.”

This, of course, appeared to be tolerably conclusive, and I was inclined to throw up the whole business at once and return to Paris, where other work urgently awaited my attention. It was clear enough from the report of the French Consul-General at Stockholm that Engström and Linner would not lend their name to any shady proceedings, while Johnson-Meads’ apparent certainty that Engström was really what he professed to be seemed to cut away the principal basis of suspicion.

Half an hour later I met Madame Gabrielle and Luigi in the same private room and showed them the three reports, which were as disappointing to them as they were to me. Of Madame Bohman, Gabrielle had failed to discover anything which could give reasonable grounds for suspicion. According to her own statement—for the resourceful Madame Gabrielle had speedily scraped up an hotel acquaintance with her—Madame Bohman and Engström were old friends, having known each other for years in Stockholm. Moreover, it was evident that Madame Bohman at least knew Stockholm well, for Madame Gabrielle was intimately acquainted with that city, and had no difficulty, by means of apparently artless conversation, in testing the accuracy of Madame Bohman’s knowledge. To all intents and purposes we seemed to be on a wild-goose chase, and I expressed this view.

“There is nothing in it,” was my verdict. “I think the best thing we can do is to give up wasting our time and get back to Paris at once. You know there is the Morny affair waiting for me, and Hecq is anxious I should take it in hand without delay.”

“The Morny affair” was one of those queer financial scandals which have been so rife in Paris during the war. A Frenchman, hitherto of unblemished reputation as a patriot, had suddenly come under suspicion of trafficking with the enemy. Questions and rumours had been flying thickly in the Paris Press, as well as in the Chamber, and it was urgently important that the unfortunate Mr Morny—for I, at least, believed he was being slandered by a group of business rivals and political enemies—should be cleared once and for all of suspicions which were rapidly reducing him to a state of complete prostration. How, later, I succeeded in completely vindicating his character, I hope to tell at some future time—at present a full disclosure of the facts might do untold harm.

But Madame Gabrielle, her feminine intuition busily at work, was not to be easily put off. She strongly dissented from my view.

“Yesterday,” she said, “during Madame Bohman’s absence with Engström at Brunner, I took Luigi’s master-key, and, entering her room, opened her dressing-case and thoroughly searched her papers. It is true I found nothing of interest, save that there were letters from certain friends in London, the addresses of which I have copied. And I found this!”

“This” was a blank sheet of notepaper, which she produced, bearing the heading of the Palace Hotel at Lisbon.

“You see,” she said, “it has been very carefully preserved, for it was enclosed in these two envelopes. I wonder why?”

I took the blank paper from her and examined it carefully. I found it to be the ordinary hotel notepaper, exactly similar to that which I myself had used in the hotel writing-room, during my recent visit to the Portuguese capital.

“Well,” I said, “I don’t see how that proves, or even suggests, anything. We know perfectly well that Madame Bohman has been to Lisbon—she herself makes no secret whatever of the fact, and she may very well have brought away by accident a sheet of the hotel notepaper and a couple of envelopes. It is true she seems friendly with both men, and there is undoubtedly some suspicion. But is it sufficient to justify action on our part, or even to give us good reason for staying here and devoting to a very trivial matter valuable time which at the moment we might be spending to much greater advantage in Paris?”

Luigi raised his dark eyebrows and shrugged his shoulders. It was obvious that he was entirely of my way of thinking, and, though he was willing to do anything to help me and to put a spoke in the wheel of the Hun plotters—for, like all patriotic Italians, he cherished the liveliest hatred for the Austro-Germans—he was no fonder than I am myself of the profitless task of chasing a will-o’-the-wisp. But the merry, go-ahead little Frenchwoman had her suspicions very thoroughly aroused, and I knew well that when this was the case it was not an easy task to allay them.

“I do not care, mon cher Gerald! There is evil work in progress, somewhere; I am confident. Why should Thornton be acquainted or have anything to do with our arch-enemy, Ernst Halbmayr? Remember how cleverly he escaped you six months ago in Rotterdam!”

“But we trapped the woman,” I rejoined grimly. “And there was a firing party at Versailles.”

“And there is somebody to be trapped here also,” persisted Madame Gabrielle. “You will surely not give up yet?”

While we were still discussing the matter a page-boy brought a telegram. Luigi took it from the lad and, dismissing him, handed the message to me. It was from Aubert in Lisbon, and it conveyed the significant news that this man Thornton had left for Lucerne, and that Garcia was travelling by the same train. “He has just sent a telegram to Syberg at the poste restante,” the message concluded.

After this, of course, there could be no question of our abandoning our task. There was evidently something afoot, and just as evidently Lucerne was likely to be the scene of some lively incidents.

Luigi did not lose a second. He rang the bell, and immediately another page-boy appeared.

“Go at once to the poste restante,” he said, “and ask for a telegram for Syberg. They know you come from me, so there will be no need of a letter. Don’t forget the name—S-y-b-e-r-g. And make haste.” The boy disappeared instantly, and for a quarter of an hour we waited in feverish impatience for his return. When he came back he brought with him the message we wanted. Opening it, I read in French, as follows:

To Syberg, Poste Restante, Lucerne.

“Received good news from London. Meads” (the man in London whose suspicions had been aroused) “is now with us, so business can proceed. Leaving for Lucerne to-night. Shall see T. in Paris to arrange further details and transit of machinery. Thyra” (the Christian name of Madame Bohman) “will meet E.H.” (was this Ernst Halbmayr?) “at Geneva on the 15th.”

This message was unsigned, but it confirmed the impression given us by Aubert’s wire that events were on foot, and at once the three of us plunged with renewed energy into our plan of campaign.

“There can be no doubt,” I said, “that ‘E.H.’ refers to Halbmayr, and probably he is directing the whole of the intricate affair.”

“Very likely,” said Luigi dryly, “but I do not see that we have much more light on what direction against the British the conspirators, if they really are German agents, intend to work.”

“True, but that is just what we have to find out,” I replied. “From what Johnson-Meads states, the plot in some way relates to the British submarines. At present I am just as much in the dark as you are. If Halbmayr is directing operations you may depend upon it that some really serious coup is intended, for Halbmayr never troubles his head about the small affairs. Don’t forget that next to Steinhauer he is the man the Königgrätzer-strasse puts most implicit faith in.”

Events were now moving rapidly. I waited with anxiety for the arrival of the man Thornton, whom I had never seen, for I was particularly anxious to have a look at him. I suspected very strongly that he was one of the German Secret Service men masquerading under an assumed name, and I was therefore particularly anxious for an opportunity of identifying him. I argued with myself that if he was mixed up with anything big enough to call for the co-operation of Halbmayr he must be one of the “big” men himself, and it was quite possible I might be able to identify him, for personally or through photographs I was well acquainted with most of the leaders of German espionage work.

Thornton at length reached the Waldesruhe, where he was greeted by the urbane Luigi with all the evidence of distinguished consideration which made the suave Italian so popular with his many patrons. Thornton would have passed for an Englishman anywhere, both in looks and language. He was perfectly dressed in clothes unmistakably British in cut, and spoke the language to perfection. This, however, was hardly surprising, for, as we learned afterwards, he had lived in London ever since he was fourteen. He had, however, been brought up in circles which were virulently anti-British, and had absorbed to the fullest extent that poisonous hatred of everything English which so frequently displays itself in the Hun who has made England his home of convenience.

He little suspected that the smiling Luigi, who so assiduously attended to his comforts, was one of the secret agents of the Allies; that another, in the person of myself, saw his arrival, or that in the turret of the great hotel there was a small secret room containing a powerful wireless set, which I sometimes operated myself.

I had to be very careful not to be seen by Thornton, for it was quite possible, if my suspicions were well founded, that he might know me. And it was well that I did, for I recognised him instantly as Emil Brahe, a German agent of whom we had lost sight for some time. He had formerly been engaged on the Continent and was well known to our men, though of late years he seemed to have dropped out of active work, and we had lost sight of him altogether. I realised now that we had been cleverly tricked: we had believed him to belong to the Berlin branch, while all the time he was living quietly in England, where he did no “business” whatever, and was thus never suspected even by the astute men of the Special Branch.

We had relied much on Madame Gabrielle’s powers to extract information from Madame Bohman, with whom she was already on excellent terms. The pair often sat chatting in the lounge, smoking each other’s cigarettes, and I knew the fair Gabrielle was keenly on the alert for any slip by which Madame Bohman might “give herself away.” The Swedish woman, however, was far too clever and would betray nothing.

Shadowing Thornton, or Brahe, to give him his right name, was Manuel Garcia, a capable ex-detective of the Lisbon police, who was now an agent of the Central Bureau of Counter-Espionage in Paris.

That telegrams were constantly passing between the Swedish engineer and some people in Lyons and Marseilles I knew, and, indeed, I was able to secure copies of some of them. In this way I discovered that these Swedes were on very friendly terms with a banker named Heurteau, who had carried on business in Paris before the war, had afterwards escaped to Zurich, and had long been suspected of being one of the paymasters of the spy bureau in Berlin.

On the morning of the thirteenth, in consequence of what Madame Gabrielle had told me, I took train to Geneva, where I put up at the National. Manuel Garcia followed by the next train, and early next morning I received a telephone message from Madame Gabrielle telling me that Madame Bohman had left the Waldesruhe and was due at Geneva at four o’clock that afternoon.

As a result of this message Garcia and I watched the incoming train, and my assistant followed Madame Bohman in a taxi to a small hotel in the Quai de Mont Blanc. An hour later Garcia himself took a cab to the hotel so as to watch for the arrival of Halbmayr, the real antagonist with whom our duel was being fought out.

Halbmayr, a short, stout, bald-headed man, with perfect manners and the air of a bon viveur, kept his appointment punctually, arriving from Bâle the next day about noon. As he knew me well, I was compelled to remain in hiding, but from my window I was able, with a pair of good field-glasses, to watch Madame Bohman and the German walking together on the Promenade du Lac, evidently engaged in the closest conversation. Garcia, of course, was not far away.

The pair remained together for an hour and a half, and I noticed with amusement that the wily Halbmayr took particular care to select a seat which stood quite in the open, with no shelter of any kind at hand behind which an eavesdropper might lurk. Garcia was thus, of course, effectually kept at a distance, and had no opportunity of gleaning anything from our enemies’ conversation.

Apparently the two, in the course of their earnest conversation, arrived at some definite agreement, for when they at length rose and parted, Halbmayr returned direct to the station, where he had left his luggage in the cloak-room, while the Swedish woman went back to her hotel, leaving for Lucerne an hour later.

By the next train I also travelled with Garcia to Lucerne. Immediately on our arrival we all had a consultation, and we were deep in talk when I received a startling message from Hecq in Paris. It had been sent to him by Johnson-Meads, who had promised to communicate with me through Hecq if any further suspicious matter came under his notice. The message read:

“Cancel my last message; most urgent I should see you immediately.”

Now Johnson-Meads’ last message had reported him as being assured of the bona fides of Engström. The “cancellation” of that could only mean one thing—that the Engström we knew was a fraud, and that for some sinister purpose he was trading on the good name of a perfectly reputable firm of engineers in Sweden.

An hour later I was on my way to London.

I arrived there without incident, and for an hour sat with Mr Johnson-Meads in his office in Fenchurch Street.

“I am afraid you will think me criminally careless, Mr Sant,” he said, “in the matter of my assurance that the man you know as Engström was what he professed to be. But I was deceived by a curious coincidence, and can only offer as an excuse that I have not had your training in solving problems of this kind.

“You will remember what I told you when I met you in Curzon Street? Well, that remains true. Where I went wrong was in identifying Engström with the head of the Swedish firm.

“It so happened that I have business friends in Malmö, and, after our conversation, being still very suspicious, I wrote to them asking for information about Engström and Linner. I soon received a reply, which was in every way satisfactory, and my correspondent mentioned, quite casually, that Mr Engström was actually in London and was staying at the Hotel Cecil. As I had that very day seen the man we now know as Engström, that seemed to me to clinch the matter, and perhaps foolishly, I dropped all suspicion.

“Now for the curious coincidence. A few days ago I was going home by train about six o’clock. The trains, of course, were packed, and I was ‘strap-hanging.’ We had just left King’s Cross when, owing to steam in the tunnel, our train ran with considerable violence into a train which was standing in the tunnel.

“The smash was not serious, but the shock was severe, and I was thrown right on top of a gentleman sitting on a seat close by me. A metal dispatch case he was carrying caught my face and, as you will see, cut it very badly. I was stunned for a moment, and when I came round I found the stranger holding me up. He tied a handkerchief round my face, and very kindly helped me out of the train to a hotel, where he got me some brandy, and I soon recovered.

“He had to go on, and as we were about to part he handed me his card. I slipped it into my pocket without looking at it, and went home, very much shaken. It was not until two days later that I looked at it. It read:

“Engström and Linner, Stockholm. Oscar Engström.

“Now, Mr Sant,” he went on, “the Mr Engström who helped me was not the man we both know as Engström! He did not resemble him in the slightest degree. I immediately tried to find Mr Engström, but found to my dismay that he had left the Hotel Cecil and no one knew where he had gone. He was on a holiday tour, and when he tears a few days from business he frequently disappears altogether for a week, in order to get a complete rest from business cares. I have wired Malmö, and all they can tell me is that he will not be back for ten days. Now what can we do?”

I thought deeply for a few moments. Obviously I must see the real Mr Engström as soon as possible. But there was no chance of finding him immediately, and in the meantime much might happen. I soon made up my mind.

“I shall return to Lucerne at once,” I said, “and go from there to Stockholm in time to meet Mr Engström on his arrival. There is nothing else to be done.”

Two days later I was back in Lucerne. “Engström,” his friend Thornton, and Madame Bohman were still there, busy on their plot, whatever it was, and entirely unsuspicious either of the urbane hotel manager or the pretty little Frenchwoman who had apparently developed a lively affection for the handsome Swedish woman.

One day I learned from Luigi that, in the course of a couple of hours, Engström had received three telegrams, and had sent a reply to each of them. Of their purport Luigi could gain no knowledge.

Now, I was particularly anxious to get a sight of those telegrams, for obviously they might throw a good deal of light on the business on which Engström was engaged. I laid my plans accordingly.

That same afternoon, with Luigi’s assistance, I managed to transform myself into a passable imitation of a very unkempt and dirty mechanic, and as soon as the Swedish engineer left the hotel, about half-past five—it was his usual habit to go out to take an apéritif—I took Luigi’s master-key, which unlocked all the doors in the hotel, and crept noiselessly to Engström’s room. I was soon inside, and a few minutes later, with the aid of my own skeleton keys, had opened the big leather travelling trunk, and was hastily examining its contents.

A number of telegrams had been hastily thrust into the trunk. I had grasped my prize and was just about to shut and relock the trunk, when I heard a sound behind me, and, turning, found myself face to face with Oscar Engström himself.

And not only that, but I was looking straight into the barrel of a very serviceable-looking automatic pistol, held without a tremor in Engström’s very capable hands!

Chapter Sixteen.

In a Tight Corner.

I was caught red-handed—caught as neatly as any bona-fide burglar who ever picked a lock!

I had opened the trunk of a fellow visitor with a skeleton key; I had been caught in the very act of pilfering the contents. Indeed, at that very moment I held in my left hand a tiny leather box containing Engström’s diamond tie-pin and studs, while with my right hand I had been delving into his big trunk. Never was a capture neater or more complete. And, with the menace of the big revolver in Engström’s hand, and knowing something of my captor, I knew better than to attempt a rush for escape. I should never have reached the door alive!

“Well, and what does this mean?” harshly demanded the Swedish engineer, in bad French, still covering me with his pistol. “And who are you?”

Had Engström suspected who I really was, I knew he would have shot me out of hand and chanced all consequences: indeed, he would have had little to fear, for there would have been nothing more than a casual inquiry into the shooting of a thief caught red-handed. Moreover, dead men tell no tales, and Engström would have had no difficulty whatever in excusing himself by some hastily concocted story that I had attacked him as soon as he found me plundering his trunk. My disguise saved me, and it was evident he had no suspicion that I was anything but a common thief.

I broke instantly into a torrent of excuses, putting down the little jewel box and the papers with as guilty an air as I could assume. The situation obviously required both tact and cunning, for I realised that I was in a tight corner and that a slip would cost me my life. I pleaded desperate poverty; I was an honest workman driven to evil courses by want; I am afraid I even invented a story of a wholly mythical wife and family in the last stage of starvation. Finally, I roundly promised amendment of my ways if he would but let me go. “Forgive me this time,” I implored. “Do forgive me—this will ruin me.”

“You dog of a thief, I have caught you stealing from my room,” was his only reply. “I shall call the manager,” and he slammed the door and pressed the electric bell. “Send the manager here at once,” he commanded the messenger who answered the bell.

Luigi came immediately, and there was a great scene in which my friend very cleverly worked himself into a state of virtuous indignation at the slur I had cast upon his hotel’s high reputation. He assured Engström that justice should be done forthwith, and actually handed me over to a police officer, and I was at once marched off as a common hotel thief.

Guess my surprise when, as soon as we had turned the first corner, the officer whispered: “Monsieur Battini has told me all the circumstances. He did not telephone to the Bureau, but called me in out of the street. Dash away from me in a few moments when we come to a lonely place, and I will merely pretend to follow you. But, monsieur, get away from Lucerne as quickly as possible.”

I smiled: Luigi had shown that he possessed a quick and ready resourcefulness. It was most fortunate that Engström, finding me with my skeleton keys on the floor, and his jewellery in my hand, had failed to suspect the truth.

I slipped away at the first convenient corner, and an hour later was well on my way by the St. Gothard route to Milan, the excellent police officer undertaking to let Luigi know whither I had gone. I learned later that, when my “escape” was reported to him, Engström took the matter very quietly, and, beyond roundly abusing the officer for letting me slip through his fingers, did not propose any further action. As a matter of fact, having lost nothing, he was probably well content that the affair should end thus. I have no doubt that, masquerading in the name of another man, publicity was the last thing he would desire.

Our problem now was how to deal with Engström and his associates. Obviously to arrest them, even if we had good ground for doing so, would have been to defeat our own object, for we wanted to find out all the details of the plot upon which they were engaged. But, as a matter of fact, they had done nothing up to this moment to bring themselves within the clutches of the law. Engström, it is true, was posing as someone else, but, so long as he did not attempt to profit by it, this was not a criminal offence. I decided to continue our investigations.

Reaching Milan, I put up at the Cavour, where, of course, I was well known. A few hours later I received a long dispatch in cipher from Madame Gabrielle, and two days later an explicit letter from Luigi. I was also able to secure some further information regarding the mysterious engineer and his friends, and this decided me to go to Sweden myself and see the real Mr Engström.

My journey to Malmö was uneventful, and, arriving there, I lost no time in repairing to the yard of Messrs Engström and Linner, the engineers. There, in the private office of the head of the firm, I soon found myself face to face with the principal, Mr Oscar Engström. He was a short, dark, alert little man, with charming manners, and I took a liking to him at once. I had not previously decided on my course of action, but after a few minutes’ conversation I decided on a policy of complete frankness. As rapidly as possible, I told him the full story of the man who had been using his name in London and on the Continent.

At first he expressed himself as completely puzzled. He could not, he said, imagine what the object of the gang could be. They could hardly commit the firm to anything which would profit themselves, for no one abroad would act without inquiries. At length I happened to mention that Johnson-Meads had told me that the man had for disposal something connected with submarines.

“With submarines!” he exclaimed in obvious surprise. “Why, we have in hand at this moment several submarine inventions, of which we own the patents. Two of them are completely secret, and they are in use only by France and Britain.”

This put a new aspect on the affair. “I begin to see now,” I said, “why your name has been assumed. Have you heard of any attempt to secure the submarine secrets?”

“None whatever,” replied Mr Engström. “Moreover, it would be extremely difficult, if not impossible. One of the appliances with which we are concerned is of such importance that, while we make the greater part of it, a vital portion is manufactured in England, and the apparatus is not put together until the whole is actually on the submarine for which it is intended. Consequently, unless a thief or spy secured copies of the plans both here and in England he would be powerless to profit by either. I may mention that this arrangement was arrived at with the British Admiralty at our express wish and suggestion. I am quite frank with you, Mr Sant.”

“One more question, Mr Engström,” I added. “You are in a position to know of any important inventions in connection with submarine work. Have you heard of any recent invention which would bring it within the bounds of possibility that your double is acting honestly and has really something to sell?”

“That is out of the question,” returned the engineer decidedly. “Unless the invention were German, in which case it would not come out of that country, I think I should certainly have heard something of it. Of course, we have rivals in our business, but there is a certain amount of freemasonry even among business rivals. I know all the people who are making submarine parts—there are very few who could or would tackle a big invention. Besides, if the man has an honest bargain to drive, why should he assume my name?”

This argument was unanswerable. But I confess I was still a long way from guessing just what the bogus Engström and his friends were plotting.

My next visit was to the Swedish police in search of information about Madame Bohman. Here, however, I was quite at fault. It was evident she was passing under an assumed name, and I could not succeed in identifying her among the long array of photographs of known German agents laid before me by the chief of the Swedish Secret Police.

Arriving at Bergen, I received, before I sailed for England, a long telegram from Madame Gabrielle, telling me that Engström, Madame Bohman, and Thornton had left for Paris. Fearing that they would immediately recognise her if she followed them, she had telephoned the news to Hecq, and that astute official had promised to take the suspects under his own wing for the immediate future, pending my arrival.

I proceeded to London, where, to my dismay, I learned that, although Madame Bohman had arrived in Paris with Thornton, Engström was missing.

Twenty minutes later I was speaking with Hecq at St. Germain over the official telephone. Three days later I heard that Hecq’s men had succeeded in running the elusive Engström to earth at Marseilles, where he was staying at the Hôtel Louvre et Paix under the name of Jansen, and was constantly meeting a compatriot named Tegelmund.

The situation at this moment remained a complete puzzle so far as the real objective of the gang was concerned. On the one hand, we had at Marseilles the mysterious individual who posed as the Swedish engineer, Engström. On the other, we had his known associates, Thornton and Madame Bohman, in Paris. Engström was living quite openly, with no appearance of concealment, at a good hotel, but he was quite obviously doing nothing and meeting nobody. The other two, however, were just as obviously lying low. They had taken apartments at a very small and not very reputable hotel in the Rue Royale, and both had changed their names, entering France with new and apparently perfectly genuine Swedish passports, issued only a few weeks previously.

Our next discovery was a staggering surprise. One of our agents, who had been watching Madame Bohman, came in and reported that, late the previous night, she had left her hotel and walked swiftly to an obscure café in the Quartier Latin. She had entered the place, taken a seat at a table by herself, and called for a glass of wine. While she was drinking it, a man, very untidy and apparently half intoxicated, lurched up to the table and sat down facing her. She took no notice of him whatever, or he of her. Calling a waiter, the man ordered a double glass of Chianti. Our agent, seated at an adjoining table, saw her then glance quickly at the stranger, and a moment later she ordered an absinthe.

Now, an order for a double glass of Chianti is unusual, especially in a disreputable café in a low part of Paris, and it is hardly customary for women to follow wine with absinthe. Our agent was struck by the oddity of the two orders and listened closely.

Directly the waiter had placed the drinks on the table and left, the man, without even glancing at the woman, muttered something in an undertone which our agent could not catch. It was, however, evidently sufficient, for the woman drank up her absinthe, and, rising, left the café. She took no notice whatever of the man, and he paid, to all appearances, as little regard to her. Apparently half overcome by drink, he remained at the table, nodding drowsily, for a quarter of an hour. It was a clever bit of acting, but he forgot his eyes! Our agent caught a sight of them, and realised at once that the drunkenness was feigned.

At length the man got up and lurched towards the door. The police agent at the same moment left by another exit into an adjoining street, and, casually turning the corner in the direction the supposed drunken man had taken, saw him a few yards ahead, walking steadily enough.

Five minutes later he had overtaken Madame Bohman, and, walking side by side for a few hundred yards, they had a brief conversation and parted.

Our agent was in a quandary. He had the strictest instructions not to lose sight of Madame Bohman, but he was a man of intelligence, and realised that a new factor had appeared on the scene. Accordingly, he decided to follow the man, and soon saw him enter a cheap boarding-house, letting himself in with a latchkey. Five minutes later we had the news, and a couple of men were at once detailed to take up the watch. Madame Bohman, we soon ascertained, had gone straight to her hotel.

The boarding-house which the mysterious stranger had entered was closely watched all night. The next morning the man came out, and was immediately recognised as none other than Halbmayr himself! How he had got into France and Paris was a mystery, for the police had no register of his arrival. I may say here that this point was never completely cleared up, but it was very generally believed that he was put ashore by a submarine, and intended leaving in the same way.

We now had him safely enough; he could not possibly escape. He was a known spy, and there was ample ground for arresting him. But this would have made mincemeat of our plans, as Hecq saw plainly enough.

“Halbmayr is very dangerous,” he declared to me as I sat in his office the same day. “Evil work is on foot somewhere, and our friend the German is director of operations. He would not dare to show his face in France after meeting Brahe in Lisbon unless he were playing for a big coup. But, my dear Sant, what is his motive? What is he after? To that question so far we have got no reply whatever. And we must find the answer.”

I agreed with my chief most cordially. “Give him rope,” I said, “and see if he does not hang himself. At any rate, he won’t escape us this time; we shall get him even if we don’t learn his secret. What worries me is that he may have done his nefarious work, and inflicted untold injury on the Allies before we nab him. But we must take some chances.”

“The telegram sent by Brahe, or Thornton, to Engström just before the former left Lisbon mentioned two things,” said my chief. “The first was that Johnson-Meads was with them—in other words, that his suspicions had been allayed (which we know to be a fact)—and that ‘T.’ was here in Paris ‘to arrange further details and transit of machinery.’ What machinery? And who is ‘T’? ‘T’ must be Tegelmund, the man in Marseilles. We must look out for him.”

Chapter Seventeen.

“The Plot Revealed.”

Within a week the man Tegelmund, accompanied by Engström, arrived in Paris and took up his abode in an obscure hotel near the Gare du Nord. But, though we kept a careful watch upon the pair, Engström, ever elusive and resourceful, suddenly disappeared! For six days he was absent. Then, as suddenly and mysteriously, he appeared again at the hotel.

Aubert, who had been detailed to watch Tegelmund, now reported that the latter had been across to the Orleans goods station, inquiring about some heavy cases of goods which had arrived from Lisbon.

“I have contrived to open one of the cases,” he said. “It contains some complicated and apparently delicate machinery, with a small dynamo. Apparently it is some sort of wireless plant, but, beyond that, I cannot make head or tail of it.”

At Aubert’s suggestion I went late one night to the Orleans goods yard. Aubert, by methods of persuasion not wholly original, had contrived to make friends with one of the officials, and we had no difficulty in securing access to the great goods shed, now silent and deserted, in which the mysterious cases lay. Prising open one end of the topmost case, I inspected the contents as closely as I could with the aid of my pocket flash-lamp. Within was what certainly appeared to be a wireless plant of some kind, but it was of a description entirely new to me, and I could not see enough of it to gain any idea of its purpose. Of course we dared not risk unpacking it. But we had made a great advance. The big cases could not be secretly moved, and our friend, the goods official, undertook to let us know promptly when he received orders to release them.

We waited in patience for a week, but still the cases remained untouched and uncalled for. Then came an incident which threw a flood of light on the proceedings of our enemies, though it told us nothing of their real motive; we were to learn that later.

One day I was strolling aimlessly along the Boulevard des Capucines, when I heard my name pronounced in accents of delighted surprise. Turning round, I instantly recognised an old friend in the person of Captain A—, who was one of the experts attached to the submarine branch of the British Admiralty.

“My dear Sant,” he exclaimed joyfully. “Who would have thought of meeting you here? I am alone in Paris. I know no one and am bored to death. What have you got on hand now? I thought you were in New York.”

“I certainly didn’t expect to meet you here,” I replied. “What has brought you over?”

“Come and have some lunch, and I’ll tell you all about it,” he replied, and we repaired to an adjoining café, where Captain A— promptly ordered lunch in a private room.

“We’ve got a new thing on hand in the submarine line,” he told me as soon as the waiter had left the room. “You know we have been trying some experiments in German waters lately, and the Hun destroyers have been so confoundedly active that our fellows have had to pass a lot of their time sitting on the bottom. As a consequence, some of the crew have suffered terribly for want of fresh air. We have a very good system of purifying the atmosphere, but it is not sufficient owing to the long periods the boats have to stay under water, and a number of men have collapsed and died from suffocation. Indeed, one boat only escaped with more than half her crew totally incapacitated.”

I was keenly on the alert. Was I, I wondered, coming to grips at last with our problem?

“Well,” Captain A— went on, “we have been offered a new apparatus, which, if half of what the inventor tells us is true, will enable us to give the Hun a very bad time. We are assured that by its help a boat can stay under water for five days without the slightest risk.”

“Five days!” I repeated incredulously. “Why, it’s impossible!”

“So I thought,” he rejoined, “but when Engström and Linner vouch for anything, you’ve got to listen.”

“Engström and Linner!” I gasped. Things were getting “warm” indeed.

“Yes,” he replied. “Mr Engström is in Paris now with his invention, and we are going to test it off Havre.”

Then I sprang my mine. “Would you be surprised to learn,” I asked, as coolly as I could, “that your Mr Engström is not Mr Engström at all, but a German agent passing under his name?”

I have seen a good many badly surprised men in my life, but I never witnessed before or since such a spectacle of hopeless astonishment as Captain A— presented when he grasped the full significance of this announcement. He sat staring at me, his mouth wide open, and with dismay written legibly on every line of his countenance.

“But, Sant,” he gasped. “Are you sure? Mr Engström came to us in London and told us all about it. He explained that the inventor was a Spaniard who would not trust the ‘neutrality’ of the Spanish Government in the matter, and that he had brought his invention to Engström’s with the idea of getting the best terms from one of the Allies.”

“I have no doubt that the man posing as Engström came to you,” I replied. “But, none the less, he is not Engström at all.”

“Then what is his game?” countered A—. “He has offered us the fullest test before we adopt his machine, and has not asked for a cent.”

“That remains to be seen,” I answered, “but it bodes no good to the Allies. What does he propose?”

“He has offered to instal the apparatus on one of our newest types,” replied A—, “and she is on her way to Havre for the purpose. We are to make any test we like, and, in fact, I am here to see the test carried out. The only condition he makes is that his machinery shall be sealed, and not opened until after the test has proved it to be satisfactory.”

I began to see light. “Did he propose to go with you?” I asked.

“No,” replied A—, rather ruefully, I fancied. “He said the machinery was so perfect that it would practically run itself from our electric accumulators, and that he would give us an absolutely free hand with it.”

“I wonder how many of you would have come back?” I said meaningly.

A— swore fervently, and I saw by the gleam in his eyes that he was fully awake to the possibilities of the trap into which he had been so nearly led.

Our task now, barring some unforeseeable contingency, was fairly easy; there was a good prospect of ensnaring our foes in the pit they had so skilfully dug for us.

“The matter is up to you now,” I told A—. “I’m going to drop out till the very last minute. But I shall be with you then. It is of the utmost importance that we shall do nothing to scare these very wary birds. What is your plan?”

“Well,” said A—, “it seems to me I had better go ahead as if nothing had happened. The arrangement is that Engström shall take his apparatus to Havre and instal it on E77. We are then to put to sea for the tests, and are to meet him later and inform him of our decision.”

“That will do all right,” I said. “I shall come on board the submarine before Engström arrives, and then I think we shall surprise him.”

A— departed at once to make the final arrangements and I busied myself in sending off some telegrams arranging for the final downfall of the Hun plotters.

A week later I found myself on board E77 at Havre. The mysterious cases had been sent on, and with them came Engström, with Thornton and Tegelmund, who professed to be interested in the venture—the former financially, the latter as the inventor. Tegelmund was in high glee at being thus afforded an opportunity of putting his device to a thoroughly satisfactory test. We also had a big surprise in the arrival of Halbmayr, who arrived in Havre under the name of Mennier. That he should have ventured on the scene at all showed how intensely interested he was.

Engström declared that the fitting of the machinery would occupy fully three days, and we, of course, humoured him in every way possible. A— made himself particularly agreeable, playing the part of host to perfection, and it was evident that the conspirators never even dreamed that their nefarious designs were suspected by the genial naval officer who showed such an enthusiastic interest in the wonderful stories with which they plied him on the merits of their great discovery.

The three days went by. Four great cases of machinery had been duly shipped on board, and Engström, Thornton, and Tegelmund spent many hours daily at their work in the interior of the submarine. Of course I could not appear—I should have been recognised at once—but among the crew of the submarine were a couple of the smartest men of the Sûreté, who kept the bogus engineer and his associates under the closest scrutiny. They reported to me that Engström appeared to be the only one of the three with any great amount of mechanical knowledge, and that, while Tegelmund worked assiduously at his machine, the others spent most of their time carefully examining the details of the British vessel, in which they showed the greatest interest. I began to get at last an inkling of the plot!

The fourth day dawned—the day of the dénouement. Early in the morning I slipped on board the submarine, and when the two conspirators arrived we made our coup.

Engström, when he came on board with Tegelmund, found himself suddenly confronted by the Commander, with a stalwart bluejacket standing on either side of him. He was curtly informed that he could not go below.

“But you promised!” he shrieked, livid with vexation.

“True!” said the Commander. “But you call yourself Oscar Engström, of Malmö, and I happen to have the real Mr Engström here.”

The engineer went white to the very lips as Mr Engström, who had come post-haste from Stockholm in response to my urgent cable, emerged from behind the conning-tower, closely followed by myself. The false Engström began a vehement protest, but ceased suddenly, for, glancing round, he saw Tegelmund also under guard. The game was up!

A few minutes later, with Engström and Tegelmund safely in irons, the Admiralty experts who had come over from London began a minute examination of the wonderful “invention.” They soon discovered that the cases contained a jumble of wires and odds and ends of mechanical scraps simply thrown together to look complicated, and of no value whatever for the renewal of vitiated air.

The real object was only revealed when we had got to the very heart of the amazing collection of rubbish. There, cunningly hidden among much that was superfluous, was a highly efficient electric motor, wonderfully made and controlling a powerful bomb by machinery, set to detonate the explosive after six hours’ running. The machinery was to have been operated by the electric batteries of the submarine, and had the E77 gone to sea and begun the “tests” of the bogus apparatus, not a vestige of the vessel or the crew would have been seen again, and the secret of her loss would have been locked for ever in the depths of the Atlantic.

But this, we found, was only a part of the plot—perhaps even the least important part. Tegelmund, finding himself trapped, turned craven and revealed the whole story. The real object of the spies was to get the fullest possible details of the internal arrangements of a British submarine of the latest type, and how well they had succeeded was shown when we cast our net a little wider.

Directly Engström and Tegelmund were in custody, an innocent-looking signal flag flew from the masthead of the submarine, and the officials of the Sûreté ashore made their pounce. Thornton and Halbmayr were seized at once at their hotel, and in their possession we found a wonderful series of drawings in which many of the secrets of the submarine were fully explained. A telegram to Paris brought about also the arrest of Madame Bohman, and a few days later the German agents were safely immured in the convict prison at Tours, where they were sent by the sentence of a court-martial summoned immediately to deal with their case. Their guilt in this particular case was too clear for any possibility of denial, but I am glad to say that their arrest opened up a way to us to deal the Hun Secret Service a blow from which it has never fully recovered. Enormous piles of documents were seized and carefully examined, with the result that numerous associates of Thornton in England found themselves in durance vile “for the duration,” and so many fingers of the Hidden Hand were lopped off that the hand itself was badly crippled for many months to come. How the fingers grew and were again cut off I hope to tell at some later date.

Chapter Eighteen.

The Mysterious Cylinders.

After over two years of strenuous work without a holiday I found myself at length free, and I found myself one morning busy in my rooms in Curzon Street making final arrangements for a trip to Worcestershire to spend a fortnight with Doris and her mother in their lovely country home. I was jaded and fagged, for I do not mind confessing that my work recently had considerably affected me, and I was looking forward with eager anticipation to the delights of a stay in the country. I had not seen Doris for some months, though of course we were in constant communication, and I was naturally longing for a sight of her.

But I was destined to another disappointment. Just as I was finishing my packing the telephone rang. I found the call was from Morgan, one of the ablest of the Government Experts on Explosives, and he had a curious story to tell me. When I had listened to what he had to say I realised with a heavy heart that my long-promised holiday must be again postponed. I rang up Doris on the telephone and, having broken the news to her, hurried off to Morgan’s office.

I found the expert in a state of utter bewilderment. He was an acknowledged authority on explosives, but a problem had been set before him which had baffled him completely.

A few days previously a mysterious explosion had occurred in some public gardens at Mile End. While a keeper was clearing away a pile of rubbish he found a curious-looking metal cylinder lying in a flower-bed, and while he was examining it it exploded with a tremendous report, injuring the man so severely that he had to be taken, in a very critical condition, to the East End Hospital.

A search by the police had a curious result. In other flower-beds a number of similar cylinders were found. They were very tiny, being only about an inch and a half in length and about a quarter of an inch in diameter. They contained a substance which was evidently the explosive. At one end a piece of wire was attached, evidently as a means of exploding them, and at the other end was a strip of soft lead.

Morgan showed me some of the cylinders, and frankly confessed his ignorance of what they contained.

“I thought I knew every explosive in existence,” he told me, “but this is something entirely new. It must be tremendously powerful, judging by the size of the cylinders and the effect of the explosion on the unfortunate gardener who found the first one.” As I held one of the small cylinders, studying it with great care, an idea came to me.

“May I borrow this for a few days?” I asked. “I think I may be able to help you.”

“Certainly,” replied Morgan; “but be careful. We don’t even know how it is exploded.”

Next day I was in Paris, and took train to Vemeuil l’Étang, some thirty miles from the capital, where I called on the manager of a certain well-known factory.

When I showed him the little cylinder he examined it with minute attention and carefully withdrew some of the mysterious explosive. This he placed under a microscope and a moment later said:

“Monsieur is undoubtedly correct! It is some of our product, herbethite, the invention of our chief director, Mr Herbeth, and the most powerful explosive known to modern science. None has been used in actual work yet, and the only sample that has left our factory is that which was stolen. It is a great secret.”

“Has some been stolen, then?” I asked quickly.

“Yes. Fortunately we discovered the thief—a workman named Pasquet—and we thought we had recovered all that had been taken. Evidently we were wrong and some of the stuff has got into bad hands. Pasquet is awaiting trial by the Assize Court of the Seine.”

I returned to Paris and saw the Minister of Justice, to whom I made a certain proposal. Not without demur, he finally agreed, and I went to the prison armed with authority for a private interview with Pasquet.

I met the thief in a small room in the governor’s quarters of the prison. I found him to be a man of about thirty, quite obviously of the hooligan type, and I soon guessed from his conversation that he had been in the first place the tool of others, who, when they had made use of him, had abandoned him to his fate.

He was naturally resentful and vindictive. I told him I had authority to offer him a free pardon, and a reward which would give him a decent start in life if he would give us the fullest information in his power. He was suspicious, however, and it was not until my promise had been confirmed by the governor of the prison himself that he consented to speak.

His promise once given, he made a clean breast of everything, and his information was so startling that I could hardly credit it. Possibly he saw my incredulity, for he said quietly: “Monsieur will find that I am telling the truth. Why should I lie? My whole life and liberty are in pawn for my veracity.”

I admitted that this was reasonable, and promised to, push things forward as quickly as possible. Something about the man had appealed to me, and I wondered whether, after all, he might not contain the makings of a decent citizen.

My first concern was to send a wire to Madame Gabrielle, who was in Edinburgh, and the following evening she met me in my rooms in Curzon Street, where I unfolded the whole story to her.

“Of course, we are not yet on firm ground,” I pointed out to her. “Pasquet alleges that the real name of his friend Shackleton is Von Schack and that he is a Prussian engineer officer.

“Pasquet first met Shackleton in London, and later on Shackleton approached him at Verneuil with another man, whom he introduced as Norman, and they offered to buy some herbethite from him for three thousand francs. Pasquet told me that he was very hard up owing to his wife’s long illness—I have ascertained that this is quite true—and the temptation proved too much for him. It is only fair to him to remember that, though he looks an abandoned ruffian, he bears a good character as a husband and father, and it seems to be the fact that the only money he spent out of that which he received from Shackleton and Norman went to purchase necessities and delicacies for his wife. The money really seems to have saved her life.

“Anyhow, he stole a quantity of the herbethite, which Shackleton and Norman packed in golden syrup tins and took to England. When Pasquet stole a second lot he was discovered, and the dangerous stuff was found at his lodgings and recovered before he could hand it over to the two men, who pretended to be English.

“One fact of importance at least is established,” I added, “namely, that Schack formerly carried on business as a watchmaker at Newcastle, and sold his business to an Englishman a month before war broke out.”

For weeks we hunted in vain for Shackleton. I visited Newcastle, and found that the man to whom he sold the business had later joined the Army. This meant a journey to France for me, and I had an interview with the man at a certain brigade headquarters in the Somme battle area.

“Shackleton was undoubtedly a foreigner and I should say probably a German,” the watchmaker, now a corporal, told me. “When he left he asked me to forward any letters that might come for him, and gave me the address—‘Care of Soulsby, High Street, Bristol.’”

With that information I went straight from the British front to the great Severn port. Here I found that Soulsby kept a newsagent’s shop near Bristol Bridge, to which letters could be addressed. He did a big business in this way, for the address was very handy for sea-going men.

Soulsby at first refused to give me the smallest information about his clients, but a sight of my authority opened his mouth, and as soon as he realised that something serious was on foot he was only too willing to help me.

“Of course, Mr Sant,” he said, “you will understand I have no knowledge whatever of the man. But I know that the Bristol Channel ports are full of spies, and it is very generally believed that few vessels leave here unknown to the German submarines lurking about the mouth of the Channel. If I can help you at all, I shall be delighted.”

I then learned that Shackleton had called about a week before, taking away several letters addressed to him, and that he usually called at intervals of a week or ten days. Soulsby promised to let me know at once as soon as he came again, and I wired to the wily Aubert to come to Bristol and keep observation.

Within three days, as I walked with my assistant along Victoria Street towards Temple Meads, he pointed out a middle-aged, keen-eyed, dark-haired man, who had little of the appearance of a Teuton. He looked like a well-dressed, prosperous business man. Yet it was he who had induced the unfortunate Pasquet to steal the herbethite, and he was certainly engaged in some nefarious and deadly plot. For although the actual volume of the stolen explosive was not great, so tremendous was its power that the quantity in the hands of our foes was sufficient to wreak almost unimaginable havoc in half a dozen cities in England. Mr Herbeth had looked very grave when he learned from Pasquet through me that the amount stolen was enough to fill two of the small cans used to hold golden syrup—about a pint and a half altogether.

“I hope monsieur will trace it in time,” he said earnestly. “There is enough of it in their possession to destroy half London.”

We soon found out that Shackleton was living in furnished rooms at Clifton and had one close friend, who, after some difficulty, we proved to be his accomplice Norman.

One morning Aubert arrived at my hotel and reported that the pair had gone to the station and taken tickets for London. At once I advised Madame Gabrielle by telephone to be on the platform at Paddington and watch them wherever they went. I myself took the next train to London, and, driving to Curzon Street, awaited her report.

But although I sat up until after two o’clock the next morning, she did not arrive and I received no word from her! What contretemps had occurred? I was seriously uneasy, for I had impressed upon her the vitally important nature of our task, and if she failed or met with any mishap we should be in a serious predicament, for we had no trace whatever of any of Shackleton’s associations in London, and anything might happen before we could run him to earth again among the teeming millions of the metropolis, the safest hiding-place on earth.

It was not until six o’clock the next evening that I received, by express messenger, a hastily scrawled note in which Madame Gabrielle said:

“Be extremely careful! They have discovered me, and I am being watched, so cannot come near you. Great things are in progress. Get someone to watch Shackleton, who is at the address below. Some great plot is in progress—that is certain.—G.”

Without a moment’s delay, I slipped round to Whitehall, and very soon an expert watcher was at the address given by Madame.

Twelve hours later, I was filled with dismay by a telephone message which told me that neither Shackleton nor Norman had been to the address given. They had both disappeared!

Chapter Nineteen.

Spy’s Letter Deciphered.

Back in Curzon Street, completely at a loss, I flung myself into a big arm-chair, and over a succession of pipes tried to piece our disconnected facts into a consecutive whole. Shackleton, or Schack, had moved from Newcastle to Bristol before the war, and I had little doubt that he had done so by express orders from the Königgrätzer-strasse. From this I argued mentally that Bristol would almost certainly be the seat of his main activities, and that his early return thither might be looked for with some degree of confidence. Added to this, we knew from the frank declaration of a high port official that the Bristol Channel towns were swarming with spies, and I felt little doubt that they were acting under Schack’s direction. On the whole, now that we had apparently lost the two men in London, Bristol seemed the most promising base for our operations.

I decided therefore to return, and, leaving Madame at the Grosvenor in London, I took Aubert with me, together with an English secret agent whom I will call Moore.

Moore took lodgings opposite Shackleton’s house in Bristol and at once opened an unwinking vigilance over the place. For a fortnight, however, there was no sign. In the meantime two letters arrived, addressed to Shackleton, at Soulsby’s. These were opened by the authorities, photographed, and, after being resealed, were delivered in the ordinary way.

In one of the letters, which had been posted in London and purported to be an ordinary business transaction, was the statement:

“We are having great difficulty with our clients Johnson and Phillips, so we have placed the matter in the hands of our solicitors for advice.”

This letter ostensibly came from a firm of estate agents in the Harrow Road. I made an immediate inquiry, and was not altogether surprised to learn that no such a firm existed. In the meantime I studied the letter on the assumption that it contained a spy cipher, and after some hours’ work succeeded in extracting from its apparently innocent contents the following startling message:

“Angorania will convey troops from Montreal on 30th proximo.”

This set me at work with furious speed. An inquiry at the port offices showed me that the great liner was at the moment lying at Avonmouth, and that she would sail for Montreal a week later in order to bring over several thousand Canadian troops.

Shackleton now made what was to me, I confess, a very welcome return to the scene. I had been seriously perturbed by the fear that we had lost him. While he was under my own immediate observation I felt capable of checkmating his designs, but the knowledge that an able enemy agent was at large and uncontrolled, with enough herbethite in his possession to create an appalling disaster, worried me more than I can tell.

Shackleton appeared on the scene the day after the delivery of the letter we had intercepted and photographed. Where he had been in the interval we never learned, but he did not arrive in Bristol from London; that was certain, for every train, day and night, was closely watched. Evidently the letter meant a good deal to him. He went at once to Avonmouth, closely followed by Moore. To our intense surprise, he seemed very well known at the docks and was freely admitted everywhere. He walked along the quays for some time, and we noted his obvious interest in the Angorania, now busily getting ready for her coming trip. We learned later that Shackleton had very cleverly wound himself into the confidence of a local shipping agent, and by this means had secured such frequent admission to the docks that his presence there was accepted almost as a matter of course.

I now began to feel practically certain that the Angorania was the object of the conspirators, and that the herbethite was the means to be adopted to bring about her destruction. But how?

Madame Gabrielle was to solve the question for us. The great liner was timed to leave at six o’clock, and an hour earlier the boat-train had arrived from London, bringing an unusually large assembly of passengers. These included several Government officials on their way to Canada, a number of highly placed military officers, and the members of two or three important war commissions.

Some time after the arrival of the train, a shabbily-dressed woman in a battered old hat pushed rudely against me. I turned, and to my amazement recognised Madame Gabrielle. She was obviously almost at the end of her strength, pallid with fatigue, and with deep circles round her eyes which spoke eloquently of exhaustion.

She made me a sign to follow her and slipped away from the crowd, which was hastening to the gangway. Directly we reached a quiet space, she gasped out:

“Norman has booked cabin Number 189 on the Angorania, in the name of Nash. I followed him to the shipping office and overheard.” A moment later she fainted and fell heavily into my arms.

I carried her at once to a waiting-room, and, handing her over without ceremony to the woman in charge, dashed at top speed for the quay where the Angorania was lying, now almost ready for departure. Not even for the sake of Madame Gabrielle would I venture a moment’s delay.

The “last bells” were ringing for the steamer’s departure as I rushed on to the quay. As I neared the gangway I saw, to my utter amazement, the man Norman stroll leisurely from the ship with the very last of the people who had been on board for the customary farewells. Evidently he was not going by the vessel at all. A moment later the gangways were withdrawn and the big liner moved away. Norman remained on the quay with the crowd, idly waving a real or pretended farewell to some supposed friend on the crowded decks.

I have cursed myself for my stupidity many times since, and even now I shudder at the thought of how nearly the dastardly plot against the liner came to success. The vessel was well under way when the idea flashed into my mind: “He has left the explosive on board!” How I failed to divine this earlier I cannot imagine. I suppose Norman’s return from the ship threw me temporarily off my guard.

But, in any case, there was not a second to be lost. The Angorania, heading down Channel, was gathering speed every moment, bearing somewhere on board enough explosives to sink her in ten seconds with the loss of hundreds of precious lives.

Boldness was the only course possible. I called a couple of dock police, and, showing them my authority, instructed them to arrest Norman at once. Before the spy could recover from his surprise, he was safely in custody and relieved of an extremely efficient automatic pistol.

And now for the Angorania. I rushed to the “competent military authority,” and briefly laid the facts before a veteran Colonel, in whom a life of splendid service to the Empire had bred a capacity for swift decision and prompt action.

“She won’t go far, Mr Sant,” he said cheerily, as he picked up the telephone.

A moment later I caught the crackle of wireless, and to my relief read the message: “To Q.Q.” (the Angorania’s code letters). “Heave to immediately and await instructions.—Port Commandant.” A few minutes later a clerk brought in the Angorania’s acknowledgment.

A quarter of an hour after I was aboard a British destroyer, which tore out into the Channel, and at thirty-five knots was flying along in the wake of the Angorania. We soon overhauled the big liner, and as we neared her could see the crowded passengers, evidently puzzled at the unexpected stoppage.

As soon as I got on board, I accompanied the Captain to his private cabin and told him the facts. Sending for the purser, he ordered him to bring on deck at once all the luggage which had come on board in the name of Nash. “And carry it carefully,” he added, as he told the purser what it contained.

By great good fortune, there was only one big trunk in the hold, and it was readily accessible. The rest of Nash’s luggage was in his cabin. We soon had the lot on board the destroyer, where the torpedo officer rapidly overhauled it.

In the big trunk, resting quite unconcealed on the top of a pile of clothes, were two tin canisters labelled “Golden Syrup.” I could not repress a shudder.

“I think this is what we want,” said the torpedo officer grimly, as he carefully picked up the dangerous canisters. And then he did a brave thing.

“If you don’t mind, sir,” he said to the Captain, “I will take them out in a boat and examine them myself.”

The Captain nodded silently, and a few minutes later the ship’s dinghy dropped over the side. The torpedo officer took his seat and rowed away alone, the canisters on the after-thwart winking in the blazing sunshine. He was literally taking his life in his hands. We could not let the liner go until we were sure we had got what we wanted, and no one could be sure that the mere lifting of the canister lids would not explode the terrible compound they contained.

Half a mile away from the ship the rowing-boat came to a stop. Through our glasses we saw the torpedo officer deliberately pick up the canisters and without hesitation prise up the patent lids. A moment later he waved to us, and at once commenced to row back to the ship.

“All right, let her go; I’ve got the stuff,” he shouted, as soon as he was within earshot, and a tremendous cheer went up from the crew, who in the mysterious “wireless” of the sea had learned what was afoot. A signal fluttered from the bridge of the destroyer. The Angorania dipped her pennant in acknowledgment, and soon the great liner was hurling herself through the sea on her interrupted journey.

The rest of the story is soon told. The herbethite, we found, was covered with a thin layer of sweets, and at the customs examination of luggage Nash had boldly lifted the lids and coolly showed the sweets to the officer. It was done so naturally as to defy any possible suspicion. But in the bottoms of the tins we found two exquisitely made detonators, fashioned in the shape of watches, and timed so as to explode the herbethite some twelve hours after the time fixed for the departure of the ship. These removed, the tins could be handled with comparative safety.

We made a clean sweep of the conspirators. No details were ever given to the public, and the stoppage of the big liner was easily explained away to the passengers. We found out that the small cylinder picked up at Mile End had been intended for the purpose of blowing up a munitions train in an important tunnel outside London, but the conspirators found the approaches too closely guarded and gave up the project. They were all sent to Paris for trial on a charge of stealing herbethite, and were eventually sentenced by court-martial to fifteen years’ imprisonment.

Madame Gabrielle, I am glad to say, received a handsome reward from the British Government, for our success was entirely due to her. She had followed Norman without food or rest or sleep for nearly three days, and was in the last extremity of fatigue when she gave me her final and all-important message. Pasquet, I am glad to say, justified the impression I had formed of him, and I had the satisfaction of seeing him develop into a respectable member of society, happy in the society of his wife, now fully restored to health, and again enjoying the confidence of his employers. We were able, through him, to account for all the stolen herbethite, and it was a relief to know that none of the terrible compound remained in the hands of our enemies.

Chapter Twenty.

A Message from the Herrengasse.

I have here put into narrative form a number of astonishing facts taken from information read and testimony given at the court-martial subsequently held upon the guilty parties. The facts which I assisted in establishing will, I believe, be found of considerable interest to readers as further revealing the subtle methods of the enemy.

For obvious reasons I have been compelled to disguise certain names so as not to bring eternal dishonour upon a great and noble family.

“And if I revealed the truth to your dear affectionate husband?” whispered the soft-voiced, well-dressed Italian. “What then—eh, Elena?”

“Madonna mia! No,” cried the dark-haired, handsome young woman, who sat at her tea-table in a great, elegantly furnished salon in one of those old fourteenth-century palazzi close to the port of Sarzana, the Italian naval station on the Adriatic.