The calm summer morning broke gloriously over the entrance to the English Channel between Land’s End and the Lizard. The sea was blue, with only a faint ripple.

Mrs. Beverley had been induced by Geoffrey to leave Upper Brook Street to spend a few weeks in Cornwall, taking Sylvia with her.Indeed, it was Sylvia who pressed her mother to go to Cornwall because Geoffrey was compelled to go down to the Marconi wireless station at Poldhu, near Mullion, where some alterations were being carried out.

The widow and her daughter had, three days before, taken up their quarters at the Poldhu Hotel, which is situated high upon the cliff within a stone’s throw of the high-power wireless station, which, at stated times by day and by night, transmits messages to ships across the Atlantic. Geoffrey had also taken up his quarters there, and from the hotel windows a wide and beautiful view could be obtained of the rugged Cornish coast, the picturesque Poldhu Cove and the wild Halzaphron Cliff standing out to sea, a rough granite headland.

Being summer, the hotel was full. The crowd was of a refined class the blatant profiteer with his bejewelled wife being happily absent. In the grounds of the hotel was a path which led to a small gate whereon was a notice—“Private. No Admittance”—the entrance to the wireless station. Beyond that gate no person was allowed to go, save by special authority from the head office at Marconi House, though most of the summer visitors longed to pass beyond and learn the secrets of that wonderful station—the first that Senatore Marconi established for communication with America.

Geoffrey had breakfasted at seven, and had crossed to the long, low-built buildings situated beneath those high, spidery aerial wires, with their tall, slender masts which withstand so well the fierce winter gales of the Atlantic. There for over an hour he had been busy making some adjustments upon the new eight-kilowatt wireless telephone which was being set up for the transmission of speech to Madrid. Then, at last, he had emerged from the power-house and walked along the gravelled path in the direction of the hotel, for he knew that Sylvia, after breakfasting with her mother, would be outside to enjoy the morning sunshine.He was not long before he caught sight of her, a fresh, smiling figure in a summer blouse and cream serge skirt. She wore no hat, and in her face showed that health given by the sunshine and sea air.

“Hulloa, Geoff!” she cried as she met the young fellow. “Up and busy already?”

“Yes,” he answered. “We’re still troubled over the set. Can’t get it working properly yet.”

“What’s going on just now?” the girl asked, for during the three days she had been there she had been an unofficially privileged visitor to the wireless station on account of her friendship with Falconer. She had begun to know some of the routine of the traffic.

Her lover glanced at his watch.

“Just twenty past nine,” he remarked. “In ten minutes they will be sending the Admiralty weather forecast to the ships. Come over and watch it going out,” he suggested, and, as she at once agreed, he turned back with her.

Already, as they approached, they could hear the dull roar of huge dynamos set in motion to test in preparation for the powerful spark transmission, and as they passed into the power-room, Geoffrey said:

“You’d better hold your fingers in your ears when they try the spark. Come, let’s have a look at the Devil’s Oven.”

And he conducted her past a number of huge condensers made of glass plates, and complicated looking machinery, to a big chamber built of brick, like a baker’s oven, through which all the messages passed out.

The door was open, and inside she saw a big rotary disc with copper points which the busy, bustling engineer in charge was examining prior to its use.

“Why is it called the ‘Devil’s Oven’?” asked the girl.

“Wait—and you’ll see,” he laughed, introducing her to the engineer, who was at work with his eye upon the clock, for at all hazards each day the forecast has to go out to time.The pair stood together watching, until, a few moments later, the engineer closed the door of the spark-chamber and passed along to the great switch-board.

“You had better hold your fingers in your ears, Miss Beverley,” he said briskly, in passing. This she did, and a second later when he pulled over the big switch, a terrific noise was set up, almost enough to break the drums of the unaccustomed ear. Then, passing to a little room, the engineer rang a bell to the transmission-room in a building a little distance away.

Next moment there came three short and one long crashes in the Devil’s Oven—electric discharges which showed blood-red through the square pane of glass in the door, though they were really intensely blue, while close by, upon a heavily insulated and protected plate, two great blue sparks were being quenched by a strong forced draught of air.

Again three short crashes followed by one long—the letter “V,” the testing letter of the alphabet.

The engineer watched the spark, and at last, deciding that it was efficient to reach to every ship across the Atlantic and far north and south across land and sea for three thousand miles, went again to the little room and rang the bell to the operator signifying “O.K.”

Next moment the crashes in the Devil’s Oven became continuous as across the ocean there was sent forth the signal “C.Q.”—the general call for all to listen—followed by the signal letters of Poldhu, “M.P.D.,” and a message from the Admiralty telling captains of ships what weather they might expect for the next twenty-four hours, followed by a storm warning.

So deafening were the heavy discharges that the girl was glad to get outside.

“Fancy!” she said. “Every ship at sea is listening to the storm warning!”

“Yes,” he replied. “Let us go and see it being sent by the key.”

They crossed to a small building which was divided into two rooms. In one were the operators on the land telegraph line to Marconi House, and in the other sat the wireless operator, a smart-looking, dark-eyed man with the telephones over his ears, tapping out the message in silence, his chin resting upon his hand. There only a slight clicking could be heard, the actual discharge being effected by a relay.

He was repeating the message he had at first sent, making, by dots and dashes, signals as set out by the message written down upon a form before him which had come over the land-wire from the Admiralty ten minutes previously.

When he had finished, he rose and wished Sylvia good-morning, for they had met on the previous day.

“I’m just off to bed, Miss Beverley,” he laughed. “I’ve been on duty all night, and we’ve had unusual traffic with Madrid. First a lot of press, and then a host of commercial messages. There’s some financial trouble in Spain, I think.”

And as the young man said this, Leonard Hamilton, the engineer-in-charge, entered the room on his morning inspection.

“Well, Cator,” he asked, addressing the operator after he had shaken hands with Sylvia, “has the forecast gone out?”

The young man replied in the affirmative, and then handed the telephone to another man, rather slimmer and fair-haired, who had just come on duty; at the same time he signed the log-book, pointing to an entry recording the fact that at seven forty-seven he had called up Madrid on the continuous-wave set, and they had not yet replied.

“Ah, the same old dodge!” declared Mr. Hamilton, himself a youngish, good-looking man. “They pretend they can’t get our ‘C.W.,’ and always want us to send on spark just because it is easier for them. They really aren’t playing the game over there. Try them again at ten, and every fifteen minutes afterwards. Is there much to go?”

“Eighteen messages.”

“You’ll get them away soon, no doubt,” the chief engineer said. “They’ve done the same old trick before. They bang over all their traffic in a bunch to us, and then tell us to stand by for half an hour.”

“They did that early this morning,” Cator said. “They ended their transmission at four, and at once told us to stand by till five. Fortunately we cleared all our traffic to them then.”

Hamilton, a most genial and delightful man, who was loved by all the staff in that outlandish corner of England, and who was one of the best known Marconi engineers, smiled, and remarked:

“I know them, Cator—I know only too well!”

And he bent to glance at the log that had been kept during the night.

When outside in the glorious morning sunshine, Geoffrey turned to the pretty girl at his side as together they walked back past the direction-finding building along the path down to the hotel, and said:

“I’m still puzzled over that affair I told you about last night, dear. It’s most mysterious. I’m certain that the man I met in the hall of the Polurrian Hotel last night was the same man. I telephoned at eight o’clock this morning, but they tell me that Mr. Martin—which was the name he gave—has left. He had a car to Gwinear Road station last night, and caught the sleeper to Paddington.”

“Because he knew that you had recognised him—eh?”

“I sincerely hope he doesn’t suspect that I recognised him,” said Falconer. “But at any rate it is, to say the least, strange that he should be down here.”

“It is,” the girl agreed. “Probably you’ll learn something further about him soon.” Then she added: “Mother wants you to come with us this afternoon to Kynance Cove. She is asking Mr. and Mrs. Hamilton and two other ladies from the hotel; we are going to picnic there.”

He began to protest that he had work to do, but later, when he consulted Hamilton, the pair decided to finish early and join the ladies at half-past three. This they did, and while Hamilton, brisk and burly, drove his wife in his own grey car, Geoffrey, in a hired car, accompanied Sylvia and her mother, and the two other ladies with whom Mrs. Beverley was slightly acquainted.

The drive was a beautiful one through one of the wildest and remotest parts of Cornwall, over the fresh breezy hills, through the old-world village of Mullion, with its narrow, crooked streets, thence up the hill to Penhale, and over the high-up straight road which leads to Lizard Town. Before reaching the town, however, they turned to the right just after passing the Travellers’ Rest, and presently found themselves down in the Kynance Cove, one of the most celebrated and most romantic spots on that rugged granite coast.

They descended in the little bay beyond which rose from the sea the Gull Rock and Asparagus Island, with its cave known as the Devil’s Throat, and walked upon the silvery sand beneath the high cliffs of beautifully veined and coloured serpentine.

“Perfectly lovely!” declared Mrs. Beverley. “Just to think that they issue a storm-warning on such a glorious day!”

“Storms at sea often brew when the weather is brightest—just as they do in our own lives, Mrs. Beverley,” Geoffrey remarked.

“Ah, you’re always so horribly philosophical,” laughed the American woman. “I suppose it’s your profession that makes you so.” Together they had mounted to the top of a grass-grown cliff, and with their picnic basket, sat down to tea, which Mrs. Beverley poured out from Thermos flasks.

From where the party sat there spread a magnificent panorama of sea and rugged coast. Before them were the two granite islands around which thousands of gulls were swooping, while eastward lay the Venton Hill and the many rocks around the Lizard—the most southerly point in England—truly a wonderful scene, so weird, rugged, and remote.

Presently, after tea, Sylvia, looking very sweet in her summer gown, wandered away with the man she loved, leaving Hamilton with the four ladies to stroll and chatter. The pair took a rocky path which ascended higher up the hill, and as they went along, Mrs. Beverley shouted after them:

“Remember, dear, we leave at six o’clock!”

The girl smiled back, waved her hand, and then went on with her companion.

Perhaps Mrs. Beverley was not altogether pleased with the situation, for her secret intention had all along been to marry Sylvia into the peerage. Had she not come to London for that purpose? Yet, after all, Geoffrey Falconer was a charming and highly-intelligent young fellow, whose several discoveries in wireless were, she had been told, likely to bring him a considerable fortune in the future.

As the pair halted on the top of the hill, Sylvia suddenly paused, and said:

“Do you know, Geoffrey, I can’t help thinking about that strange man you saw in the Polurrian last night.”

“Yes,” he said. “Somehow I, too, can’t forget him. I first met him in the wagon-restaurant of the express from Paris to Calais about three weeks ago. He sat at the next table, and though he was reading the Matin between the courses at lunch, I noticed that he seemed to be watching me.”

“Not another Edward Everard, I hope,” said the girl, whose hair was being blown across her face by the sea breeze which was just springing up.

“I hope not,” laughed her merry lover. “But he seems to have followed me so persistently. Why I cannot tell. Possibly he may have learnt my profession, and of my post in the Marconi service.”

“And if he has, then, what motive has he for following you? One thing is reassuring. Your secret diagrams are now in a safe place. When did you see him again after meeting him in the train?”

“On the boat, crossing to Dover. Then I lost sight of him, until one morning, when I arrived by train at Chelmsford as usual, I saw him lounging downstairs in the booking-hall. At first I did not recognise him, but after I had passed and was walking along that path which is the short cut to the Works, I recollected the incident on the Calais express. Then it all passed from my mind again until I encountered him accidentally in the lounge of the Polurrian. Why was he here?”

“Perhaps to spend a week by the sea!” laughed Sylvia.

“Hardly that!” Falconer said. “He was down here for some distinct purpose. And that purpose I mean to discover. I intend to establish why he came down here so near the Poldhu station and stayed the night as Mr. Martin. Remember, only the other day he was at Chelmsford, and now he had been to Poldhu, and left hurriedly after seeing me.”

“Perhaps he never expected you were here.”

“That’s exactly my opinion. Probably my presence has frightened him off. I only hope it has. Nevertheless I don’t like the situation. Something is amiss somewhere—and I intend to fathom it.”

“The man is not English, you told me. Why should he go under the name of Martin?”

“Martin is a name not unknown in France,” Falconer remarked. “He may be French. Indeed, I recollect when I first saw him in the train I put him down as a Parisian.”

Both Sylvia and her lover were much puzzled. It certainly was annoying to be watched as Falconer had evidently been.

That evening they drove back over the Cornish hills with the sun setting away across the Atlantic. But already the breeze was increasing. The storm prophecy of early morning was being fulfilled.

Together they dined pleasantly in that long room at the Poldhu Hotel which overlooks the pretty cove, Mr. and Mrs. Hamilton dining with them. Afterwards they all went across the wide grounds of the wireless station to the Hamiltons’ pretty bungalow, where they spent the remainder of the evening.

Hamilton was a typical Marconi man, burly, easy-going, and refined. An expert wireless engineer, he had worked stations in India, South America, and other places, and ran a secret station during the war—a station which had to its credit the destroying of many German submarines. With his charming, dark-haired, cosmopolitan wife who that night was hostess to the wealthy South American widow, he had lived in all sorts of outlandish places in the shadow of wireless aerials, ever on duty day and night with the alarm-bell at his bedside in case of a breakdown.

Of wireless troubles he had many. Yet he was one of those easy-going golfers whom nothing disturbed. He was devoted to his wife; he led an ideal life in his picturesque, roomy bungalow in that wild, windswept spot overlooking the Atlantic, and he smoked his pet pipe, and never allowed anything to upset him. With all the public schoolboy spirit, he was devoted to his duty, and though severe and just, was yet highly popular with his whole staff.

In that bungalow the Hamiltons led a charming existence, though, if judged by life in London, it might be voted terribly dull. So it was in winter when there were no summer visitors at the hotel. But even then they had the society of the little colony of Marconi men who lived in other bungalows and down in Mullion or in Cury.

Sylvia was delighted with Mrs. Hamilton’s outspoken cosmopolitanism. She had been in half-a-dozen different lands with her husband, and her bungalow life suited her, even though servants were, perhaps, hard to keep in that remote spot. But her house was well-ordered, and furnished with great taste, a fact upon which Mrs. Beverley commented.

In the long drawing-room where the furnishings showed souvenirs of travel far afield, the chief engineer and Geoffrey smoked their cigarettes, while the ladies gossiped. Presently the two men left and entered the dining-room for a drink before parting. Then Geoffrey, as they sat near the table together, told his colleague of the strange movements of the visitor to the Polurrian Hotel.

“Very funny!” agreed Hamilton, who at that moment was lighting his beloved briar. “What can he be doing down here? Of course, we have lots of people trying to pry around the station. But I always take a very firm hand. Nobody sees anything except by signed order from the head office. It wouldn’t do to take strangers into the transmitting room where they could read any of the messages.”

“Of course not,” Geoffrey said. “But I intend to follow up the fellow and see what his game is. I don’t like being spied upon like this.”

“Yes, try to solve the mystery,” replied the engineer-in-charge.

Next day Geoffrey was early astir. At six o’clock he was already out and over at the wireless station, making some tests upon the new gear, and at nine, after a hurried breakfast at the hotel, he walked over to the Polurrian, where, from the hall-porter, he learned several facts. The visitor, Mr. Martin, had arrived by the evening train from London, had dined, and had gone out for about an hour on foot in the evening light—across the cliffs in the direction of Pradanack, he believed. Then he came back and went early to bed. All next day he had lounged about the hotel, chatting with several of the ladies. Just before dinner he had suddenly ordered a car and told them at the office to ring up the stationmaster at Penzance and secure a sleeper to Paddington, and that he would join the train at Gwinear Road.

Later in a hired car Geoffrey drove to the little town of Helston, and took train to the terminus of that winding branch-line which ends at Gwinear Road, on the main line from Penzance to Paddington. From the stationmaster there he learnt that Martin had joined the night mail to Paddington. He also learnt something further—namely, that he had despatched a telegram to a person named Meyer at an address in Hertford Road, Bayswater. The words were: “Thursday at eleven.”

At once Geoffrey decided to return to London. Therefore, he telephoned to Hamilton at Poldhu asking him to tell Mrs. Beverley that he was called to town, and promising to be back very soon.

An hour later he was in the slow train for Plymouth, and that night, the night of Wednesday, he was back in London.

At midnight he passed the house in Hertford Road, Bayswater. It was in darkness, but was evidently a place where apartments were let, quite a respectable house of the usual Bayswater type.

He slept at the Great Western Hotel at Paddington, without even a clean collar, be it said, and just before eleven o’clock next day he stood looking idly into a shop window in Westbourne Grove, at the corner of Hertford Road, pretending not to be interested in any passer-by.

At about a minute before eleven the mysterious Mr. Martin, smartly-dressed and walking jauntily, turned the corner behind Falconer, and passing up Hertford Road, rang at the door of the house which the young wireless engineer had examined on the previous night.

In a few seconds the door was opened by a maid, and Mr. Martin disappeared within.

A girl of about eighteen, who looked like a dressmaker from one of the several establishments in “The Grove,” was the only person in the road at the moment. Geoffrey noticed her. She was rather poorly-dressed, and seemed to be searching for some house, the description of which she did not recognise.

Gaining the corner of Westbourne Grove, she was met by a quietly-dressed, middle-aged man, to whom she spoke a few words hurriedly. The man replied, apparently telling her something. Then with a smile they parted, the girl going in the direction of Queen’s Road, and the man, who seemed to be an idler, calmly filling his pipe and lighting it as he stood at the junction of the two thoroughfares.

Geoffrey saw all this, but it did not strike him as in any way peculiar. In London many men meet girls at the corners of streets, speak a few words to them, and then pass on. There was nothing really unusual about the girl’s action.

Falconer’s chief concern at the moment was not to be recognised by the man who had, no doubt, watched him when coming over from Paris, where he had been on business for his company—the man who had taken alarm on seeing him down at Poldhu. For over an hour carefully he watched the door of that house in Hertford Road, taking every precaution that he was not observed from the windows. If anything sinister was in progress, then, no doubt, somebody would look forth to see that all was clear and that there was no watcher.

Half an hour after noon the door suddenly opened, when the mysterious Martin emerged, and passing out of the gate, turned back in the direction where Falconer was watching.

Fortunately he drew back in time to escape recognition, and to watch Martin enter a taxi and drive away. Another taxi was near the kerb, therefore in it he followed the foreigner away to North London, to a small, rather dingy shop where electrical appliances were sold—a shop well known to wireless experimenters who are in search of odd and second-hand apparatus and bargains of every description.

The man remained in the place for nearly half an hour, but so blocked up was window and door that the passer-by in Chalk Farm Road could not get a glimpse within. The establishment was one of the most antique in London, and patronised widely by amateurs as well as the greatest scientists in that city.

Presently he came forth bearing a good-sized wooden box, which he put on the front of the taxi, and then drove to the Hotel Russell, where he entered and dismissed the taxi.A judicious chat with the hall-porter revealed the fact that the name under which the stranger was known was Mr. Charles Lazarus. And he declared himself as a French subject.

With this knowledge Geoffrey engaged a room at the hotel and started to keep strict surveillance upon the stranger. The man’s movements were most mysterious. That same evening he met three other men, palpably foreigners, at the CafÉ Royal, where they dined together expensively, and afterwards all four drove in a taxi to a big double-fronted house in Maresfield Gardens, Hampstead.

Some time after they had been inside, Geoffrey managed to slip into the small front garden, and, approaching stealthily one of the lower bay windows, listened. He distinguished men’s voices, though he could not hear what words were being uttered. He thought they were speaking in French.

Suddenly he heard a sharp metallic clicking. Instantly he recognised it as the tick of a Morse telegraph “sounder.” The letters of the alphabet were being sent both rapidly and well. There was no message—merely the letters A to Z, followed quickly by the numbers 0 to 9. They were evidently testing some apparatus.

He looked about to see any telegraph wires around the house, but the night was too dark and overcast to enable him to distinguish anything.

What was happening within, he wondered? The sound was certainly that of either a post-office telegraph transmitter or receiving “inker.” The click was too familiar and too pronounced for him to be mistaken.

Fearing discovery he withdrew, and then he waited in a dark doorway for the reappearance of the man upon whom he was keeping observation. Martin came out very soon after eleven o’clock, and walking down to Swiss Cottage station, took train, and made his way back to the hotel.

Falconer became more than ever puzzled. What was the connection between this Frenchman’s visit to Poldhu and the tapping of that Morse key? Of some sinister plot he felt convinced. Why should the stranger have watched him so closely in the train to Calais, and then flown on being recognised at the Polurrian Hotel?

Next morning after breakfast he went to the hall-porter of the Hotel Russell, and casually inquired whether he had seen Mr. Lazarus.

“The gentleman left at seven-thirty, sir,” was the man’s prompt reply. “I put his luggage on a taxi, and I heard him tell the man to drive to Paddington.”

Paddington! Had the man of mystery returned to Cornwall? That was Falconer’s thought.

Quickly he drove in a taxi to Paddington, where he ascertained from the booking-clerk that four first-class return tickets had been issued to Truro that morning. He described the man Martin as the person who had paid for them. Eager not to lose sight of the four foreigners, Falconer hurried to Marconi House, and was soon on the private land-telegraph line which connects the head office with the wireless station at remote Poldhu—the line over which all the messages are sent to and from London.

Seated at the telegraph-key, Falconer was soon talking by Morse to one of the assistant-engineers named Benfield, Mr. Hamilton having gone into Helston to see after the delivery of some overdue machinery which had been sent from the works at Chelmsford.

To Benfield he described Martin and his companions, and asked him to motor over to Truro, meet them on arrival, and watch where they went. He added that he should take the next train down to Truro, where he would, on arrival, meet Benfield at the Red Lion. He also sent a message through Benfield to Sylvia telling her of his movements.

At noon he was in the express due to reach Truro three hours after the arrival of the mysterious four. At seven o’clock that evening he entered the old-world Red Lion Hotel, and found Benfield awaiting him with disappointing news.

No men answering the description of the four foreigners had arrived at Truro by the London express which had left Paddington at ten-thirty and had previously arrived.

Geoffrey was nonplussed. His plans had gone entirely wrong! That some mischief was intended he felt assured. His intuition told him that Martin and his companions should be watched, but evidently they had very cleverly evaded pursuit.

They might have purposely broken their journey at Exeter or at Plymouth. Therefore, he met three other possible trains from London, yet each time he was doomed to disappointment. That they had taken tickets to Truro was no evidence that they intended to alight there. They might have got out at some wayside station.

So after the arrival of the half-past ten train that night there was nothing to do but hire a car, and, accompanied by Benfield, he returned to Poldhu, arriving there half an hour after midnight.

The wireless station was brilliantly lit. The great generators were going, ready for the commencement of the night’s heavy traffic, for real work commences there at one o’clock in the morning, because, as all wireless men know, daylight interferes with the strength of wireless signals, so most of the cross-Atlantic traffic and that to distant ships is carried on from that remote corner of England between nightfall and dawn.

Falconer, after a chat with Hamilton, went back to the hotel, where he slept till six, and then, after an early breakfast, drove by car back to the Red Lion at Truro. For three days he remained there, eagerly watching the arrival of every train, but he saw nothing of the men who had so cleverly evaded his watchfulness. It now became quite evident that Truro was not the real destination of Martin and his companions.

On the fourth day, however, at sundown, as he was passing out of the smoking-room of the old-fashioned hotel through the lounge into the busy street, it being market day, he chanced to glance to the left at the crowd of farmers standing at the public bar, when suddenly he caught sight of a man whom he instantly recognised as having been one of Martin’s companions at the CafÉ Royal. In broken English the man was inquiring of the barmaid the way to Tregoney, and she was telling him that it was about six miles out on the Plymouth road, and that he could get a taxi at the garage opposite the hotel.

Falconer held his breath, and paused.

It was evident that the stranger had only just arrived in Truro. Tregoney—the young man recollected the name. Ten minutes later he learnt that the place was a small village on the main road to Plymouth, between Truro and St. Austell. So he allowed the foreigner to go, and waited in impatience till night fell, when he hired a car, and, with a little flash-lamp in his pocket, drove to the outskirts of the remote village. There he ordered the taxi-driver to wait for an hour, and then went on to seek what information he could.

Halfway along the village street, where lights showed in the windows of most of the cottages, he came to a small inn, which he entered and ordered some cold beef and a bottle of beer. Landlords of inns are proverbially talkative to their good customers, and from the burly Cornish host Geoffrey, as he ate his meal, was not long in ascertaining that a strange foreign gentleman, whose description tallied exactly with Martin, had taken a large house at the farther end of “the town.” He was a stranger who had come over to England for his health, and he had rented the place furnished from old Miss Trethowen, who had gone to live in London for six months.

The foreign gentleman had only arrived three days before, and as far as the landlord knew had not yet engaged any servants, except a deaf old woman named Grey, who had acted as Miss Trethowen’s caretaker. Nobody in the village had ever seen the foreign gentleman before. He had arrived with a companion, a tall, thin-faced young man, and they had but little luggage except two large wooden boxes.

Having ascertained these facts, Geoffrey finished his meal and walked along the high road until he came to a large, old-fashioned house, standing back in the darkness from the road, along which ran many telegraph wires. A carriage-drive led up to the place, which seemed very lonely and neglected.

In a window of the first floor there showed a light. Geoffrey, treading softly, entered the gate and silently crossed the rough grass towards the house. Scarcely had he reached the short flight of steps before the front door, being very cautious because a house dog might be about, when he heard a familiar click-click-clickety-click—the noise of a Morse “sounder.”

It was again the same sound he had heard in Hampstead. Why? Had they, he wondered, been testing some instruments there—instruments bought of the dealer in Chalk Farm Road?

In the darkness he strained his ears. What he read by those dots and dashes amazed him. He stood aghast for a few moments.

Then, having listened intently to make quite certain that his discovery was an absolute fact, he stole quietly away, and walking back through the village, re-entered the taxi and drove back over to Poldhu.

His suspicions had been confirmed! Though it was very late when he arrived, he found Hamilton in his pretty bungalow, and told him of his strange discovery.

“You’ll take every precaution in secret, won’t you?” urged Falconer. “Nobody must know of this.”

“Trust me,” replied the engineer-in-charge, at once eager and ready.

“We’ve only to wait and be very watchful. There’s some clever game afoot, without a doubt,” Falconer said, and presently he went along the path to the hotel, and to bed, while Hamilton, even at that late hour, crossed to the transmission room for a final look round before retiring.

Next day Geoffrey, who confided his suspicions to Sylvia, became very active. Several hours he spent in the transmission room, where Cator, with the “Brown receivers” over his head, was very busy transmitting and receiving acknowledgments. Falconer was watching every message, and also spent much of his time in the adjoining room, where the land-line from Marconi House was constantly working.

A dozen times that morning he was in close consultation with Hamilton. Then, at about five o’clock in the afternoon, both drove in Hamilton’s car into Truro.

Till about half-past nine they waited at the hotel, when they drove out to Tregoney, and, leaving the car at the little inn, they both walked along to the village post-office, where, even though so late, they saw the postmaster and explained that they were awaiting an urgent telephone message from the wireless station at Poldhu. Hamilton having made himself known, the postmaster at once agreed to send along to the inn—only a few yards distant—and call them when they were wanted.

Then the pair returned to the inn and ordered supper. Scarcely were they halfway through it when the postmaster himself hurried in and announced that Poldhu was on the line.

Hamilton rose instantly and dashed out. Five minutes later he returned.

“All right!” he said breathlessly. “It’s just what you expected, Falconer. Henway, the chief constable of Truro, and four of his men are awaiting us just down the road.”

Together the pair went out into the darkness, and at the end of the village the chief constable came out from the shadows to join them. After a few words from Hamilton, the police official whistled softly, and from nowhere, apparently, four of his assistants appeared.Then whispering softly all went along to Miss Trethowen’s house, and slipping one after the other into the garden, they surrounded it. This effected, Henway rang boldly at the door, but received no answer. There was no sign of the clicking of the Morse instrument. All was quiet. Thrice he rang, when at last the bolts were drawn, and the thin man, whom Falconer had seen in the Red Lion in Truro, cautiously opened the door.

Next second the police rushed in. Henway and Falconer were first inside, and turning into a room on the left of the hall, which was Miss Trethowen’s dining-room, they saw upon the table a most up-to-date Morse telegraph instrument with wires attached to it trailing along the red Turkey carpet and out of the window.

The commotion caused by the entry of the police was great. All four occupants of the house were utterly staggered when Henway ordered their arrest on a charge of tapping telegraph wires, the property of the Postmaster-General, and with the interference of the secrecy of messages.

The man Martin instantly showed fight, firing three revolver shots point-blank at Falconer, none of which, very fortunately, took effect. The fellow was, however, quickly overpowered, and all four were later on conveyed to Truro police-station and placed in the cells.

To cut short this narrative of the romance of wireless, it is sufficient to explain that, as was afterwards discovered, the man who called himself Martin was an expert French bank thief, who had committed many great swindles both in Europe and America. In this particular case he had succeeded in obtaining, under threats of blackmail from a hard-up bank-clerk in Madrid, a copy of the secret code used by the London office of the Estremadura Bank—a great Spanish banking corporation—when ordering telegraphic payments to be made from the head office in Madrid.

With his three associates, one of whom was an ex-telegraphist of the post-office at Aranjuez, near Madrid, Martin had come to England, having purposely followed Falconer from Paris, knowing him by repute as a Marconi engineer.

His movements had at first been closely followed, for the Metropolitan police had been warned of Martin’s arrival, and he had been shadowed to Hertford Road by a girl in the employ of Scotland Yard. But afterwards, so honest did the man appear, that the surveillance had been dropped, and it had remained to Geoffrey to investigate the plot.

Martin had, as it was afterwards proved, bought in Chalk Farm Road certain component parts of a very sensitive and up-to-date appliance for tapping the land-line from London to Poldhu, which runs from Plymouth to St. Austell, and past Miss Trethowen’s house to Truro and Poldhu.

By tapping the trunk telegraph wire that night Martin had been able, by a very ingenious arrangement which Falconer afterwards examined, to despatch an urgent message to Poldhu just as though it had been received over the counter in the office in Fenchurch Street, in London, and tapped out from Marconi House. Thus the conspirators had been able to interpose a false message which they intended should be sent by wireless from Poldhu to Madrid.

The whole plot was extremely cleverly conceived, for on that night, just before Hamilton rang up Poldhu, they had sent instructions in code presumably from the London office in Lombard Street to the head office in Madrid ordering the bank to pay to a certain SeÑor Alfonso Fonesca, living in the Calle Zorilla, in Madrid, the sum of thirteen thousand five hundred and eighty pounds sterling at the current rate of exchange.

Needless to record, the false message which had been so cleverly imposed upon the land-wire was never dispatched from Poldhu, for that night all messages had been suspect, and the one in question was held back.

At the time of writing, Martin—who at the Court Assizes at Bodmin was proved to be a Swiss subject—is serving a term of seven years’ penal servitude, as well as his three companions, all of whom were Belgians.

Happily the bogus message they sent from Tregoney did not, as they hoped, pass through the “Devil’s Oven” and out into Space. So the bank was saved a theft of nearly fourteen thousand pounds.