Quick on the heels of the case of the Burnt Barn followed the next of the Red Triangle affairs. Indeed, the interval was barely two days. Mr. Victor Peytral, it will be remembered, had declined to reveal to Hewitt the addresses of the two houses in London which he had seen Mayes visit, desiring to think the matter over for a few days first; but before any more could be heard from him, news of another sort was brought by Inspector Plummer.

It may give some clue to the period whereabout the whole mystery of the Red Triangle began to be cleared up if I say that at the time of Plummer's visit this country was on the very verge of war with a great European State. It is a State with which the present relations of England are of the friendliest description, and, since the dreaded collision was happily averted, there is no need to particularise in the matter now, especially as the name of the country with which we were at variance matters nothing as regards the course of events I am to relate. Though most readers will recognise it at once when I say that the war, had it come to that, would have been a naval war of great magnitude; and that during the time of tension swift but quiet preparations were going forward at all naval depÔts, and movements and dispositions of our fleet were arranged that extended to the remotest parts of the ocean.

It was at the height of the excitement, and, as I have said, two days after the return of Hewitt and myself from Throckham, when the case of the Burnt Barn had been disposed of, that Detective-Inspector Plummer called. I was in Hewitt's office at the time, having, in fact, called in on my way to learn if he had heard more from Mr. Victor Peytral, for, as may be imagined, I was as eager to penetrate the mystery of the Triangle as Hewitt himself—perhaps more so, since Hewitt was a man inured to mysteries. I had hardly had time to learn that Peytral had not yet made up his mind so far as to write, when Plummer pushed hurriedly into the room.

"Excuse my rushing in like this," he said, "but your lad told me that it was Mr. Brett who was with you, and the matter needs hurry. You've heard no more of that fellow—Myatt, Hunt, Mayes, whatever his name is last—since the barn murder, of course? Has Peytral given you the tip he half promised?"

Hewitt shook his head again. "Brett has this moment come to ask the same question," he said. "I have heard nothing."

"I must have it," said Plummer, emphatically. "Do you think he will tell me?"

Hewitt shook his head again. "Scarcely likely," he said. "He's an odd fellow, this Mr. Peytral—a foreigner, with revenge in his blood. I have done him and his daughter some little service, and he told me all his private history; but he seemed even then disposed to keep Mayes to himself and let nobody interfere with his own vengeance. But I will wire if you like. What is it?"

"I'll tell you," said Plummer, pushing the door close behind him. "I'll tell you—in confidence, of course—because you've seen more of this mysterious rascal than I have, and—equally in confidence, of course—Mr. Brett may hear, too, since he's been in several of the cases already. Well, of course, we all know well enough that we want this creature—Mayes, we may as well call him, I suppose, now—for three murders, at least, to say nothing of other things. That's all very well, and we might have got him with time. But now we want him for something else; and it's such a thing that we must have him at once, or else"—and Plummer pursed his lips and snapped his fingers significantly. "We can't wait over this, Mr. Hewitt; we've got to have that man to-day, if it can be done. And there's more than ordinary depending on it. It's the country this time. The Admiralty telegraphic code has been stolen!"

"By Mayes?"

Plummer shrugged his shoulders. "That's to be proved," he said; "but he was seen leaving the office at about the time the loss occurred, and that's enough to set me after him; and there's not another clue of any sort. Mr. Hewitt, I wish you were in the official service!"

Hewitt smiled. "You flatter me," he said, "as you have done before. But why in this case particularly?"

"It's a case altogether out of the ordinary, and one of a string of such, all of which you have at your fingers' ends. And I don't mind confessing that this man Mayes is a little too big a handful for one—for me, at any rate. I wish you could work with me over this; in fact, in the special circumstances I've a good mind to ask to have you retained, as an exceptional measure. But the thing's urgent, and there's red-tape!"

Hewitt had taken a glance at his desk tablet, which he now flung down.

"I'll do it for love," he said, "if necessary. My appointment list is uncommonly slack just now, and even if it weren't, I'd make a considerable sacrifice rather than be out of this. This fellow Mayes is a dangerous man; and I feel it a point of honour that he shall not continue to escape. Moreover, I have begun to form a certain theory as to the Red Triangle, and all there is at the back of it—a theory I would rather keep to myself till I see a little more, since as it stands it may only strike you as fantastic, and if it is wrong it may lead some of us off the track; but it is a theory I wish to test to the end. So I'm with you, Plummer, if you'll allow it; and you can make your official application for a special retainer or not, just as you please."

Plummer was plainly delighted.

"Most certainly I will," he said. "Shall I give you the heads of the case, or will you come to the Admiralty and see for yourself?"

"Both, I think," said Hewitt. "But first I will send a telegram to Peytral. Then you can give me the heads of the case as we go along, and I will look at the place for myself. I am in this case heart and soul, pay or no pay—and I expect my friend Brett would like to be in it, too. Is there any objection?"

"Well," Plummer answered, a little doubtfully, "we're glad of outside help, of course, but I'm not sure, officially——"

"Of course you are always glad of outside help," Hewitt interrupted, "and in this case we may possibly find Brett more useful than you think. Consider now. He has seen a good deal of these cases—quite as much as you, in fact—but he is the only one of the three of us whom Mayes does not know by sight. Remember, Mayes saw us both in the affair of Mr. Jacob Mason, and he saw you again in the case of the Lever Key—escaped, in fact, because he instantly recognised you. I'll answer for Brett's discretion, and I'm sure he'll be glad to help, even if, for official reasons, you may not find it possible to admit him wholly into your counsels."

Of course I willingly assented, and the conditions understood, Plummer offered no further objection. Hewitt despatched his telegram, and in a very few minutes we were in a cab on the way to the Admiralty.

"This is the way of it," Plummer said. "You will remember that when we lost Mayes at the end of the Lever Key case, I was waiting for him in that city office, with an assistant, and that we only saw him for an instant in the lift. Well, that assistant was a very intelligent man of mine, named Corder—a fellow with a wonderful memory for a face. Now Corder is on another case just now, and we'd put him on, dressed like a loafer, to hang about Whitehall and the neighbourhood, watching for some one we want. Well, this morning there came an urgent message to the Yard from the Admiralty, to ask for a responsible official at once, and I was sent. As I came along I saw Corder lounging about, and of course I took no notice—it would not do for us people from the Yard to recognise each other too readily in the street. But Corder came up, and made pretence to ask me for a match to light his pipe; and under cover of that he told me that he had seen Mayes not an hour before, coming out of the Admiralty. At this, of course, I pricked up my ears. I didn't know what they wanted me for, but if there was mischief, and that fellow had been there, it was likely at least that he might have been in it. Corder was quite positive that it was the man, although he had only seen him for a moment in the lift. He hadn't seen him go into the Admiralty office, but he was passing as he came out, and noted the time exactly, so that he might report to me at the first opportunity. The time was 11.32, and Mayes jumped into a hansom and drove off. He walked right out into the middle of the road to stop the hansom—you know how wide the road is there—so that Corder couldn't hear his direction to the cabman, but he took the number as the cab went off. Corder ought to have collared him then and there, I think, but he was in a difficult position. It would have endangered the case he was on, which is very important; and besides, he didn't realise how much we wanted him for, having only been brought in as an assistant at the tail of our bond case. Still less did he guess—any more than myself—what I was going to hear at the Admiralty office."

"At any rate," interrupted Hewitt, "you've got the number of the cab?"

"Here it is," Plummer answered, "and I've already set a man to get hold of the cabman. You'd better note the number—92,873."

Hewitt duly noted the number, and advised me to do the same, in case I should chance to meet the cab during the afternoon; and as we neared our destination Plummer gave us the rest of the case in outline.

"In the office," he said, "I found them in a great state. A copy of the code, or cypher, in which confidential orders and other messages are sent to the fleet all over the world, and in which reports and messages are sent back, had disappeared during the morning. It was in charge of a Mr. Robert Telfer, a clerk of responsibility and undoubted integrity. He kept it in a small iron safe, which is let into the wall of his private room. It was safe when he arrived in the morning, and he immediately used it in order to code a telegram, and locked it in the safe again at 10.20. Two hours later, at 12.20, he went to the safe for it again, in order to de-code a message just received, and it was gone! And the lock of the safe is one that would take hours to pick, I should judge. There isn't a shade of a clue, so far as I can see, except this circumstance of Mayes being seen leaving by Corder—just between Telfer's two visits to the safe, you perceive. And of course there may be nothing in that, except for the character of the man. And that's all there is to go on, as far as I can see. I needn't tell you how important the thing is at a time like this, and how much would be paid for that secret code by a certain foreign Government. We have made hurried arrangements to have certain places watched, and as soon as I have taken you to the office I must rush off and make a few more arrangements still. But here we are."

Mr. Robert Telfer's room was at the side of a long and gloomy corridor on the upper floor, and the door was distinguished merely by a number and the word "Private" painted thereon. We found Mr. Telfer sitting alone, and plainly in a state of great nervous tension. He was a man of forty or thereabout, thin, alert, and using a single eye-glass. Plummer introduced us by name, and rapidly explained our business.

"I told you the name of the party I am after, Mr. Telfer," Plummer said, "and I went straight to Mr. Martin Hewitt, as being most likely to have information of him. Mr. Hewitt, whose name you know already, of course, is kind enough, seeing we're in a bad pinch, and pushed for time, to come in and give us all the help he can. Both he and his friend, Mr. Brett, know a good deal of the doings of the person we're after, and their assistance is likely to be of the very greatest value. Do you mind giving Mr. Hewitt any information he may ask? I must rush over to the Yard to put some other inquiries on foot, and to set an observation or two, but I'll be back presently."

"Certainly," Mr. Telfer answered, "I'm only too anxious to give any information whatever—so long as it is nothing departmentally forbidden—which will help to put this horrible matter right. Please ask me anything, and be patient if my answers are not very clear. I have been much overworked lately, as you may imagine, and have had very little sleep; and now this terrible misfortune has upset me completely; for, of course, I am held responsible for that copy of the code, and if it isn't recovered, and quickly, I am ruined—to say nothing, of course, of the far more serious consequences in other directions."

"That is the safe in which it was kept, I presume?" Hewitt said, indicating a small one let into the wall. "May I examine it?"

"Certainly." Mr. Telfer turned and produced the keys from his pocket. "The code was here, lying on this shelf when I needed it this morning at ten. I took it out, used it, returned it to the same place exactly, and locked the safe door. Then I took the draft of the telegram, together with the copy in cypher, into the Controller's room, gave it into safe hands, and returned here."

Hewitt narrowly examined the lock of the safe with his pocket lens. "There are no signs of the lock having been picked," he said, "even if that were possible. As a matter of fact, this is a lock that would take half a day to pick, even with a heavy bag of tools. No, I don't think that was the way of it. You have no doubt about locking the safe door at 10.20, I suppose, before you went to the Controller's room?"

"No possible doubt whatever. You see, I left the whole bunch of keys hanging in the lock while I coded the telegram. It was a short one, and was soon done. Then I returned the code to its place, locked the safe, and then used another key on the bunch to lock a drawer in this desk. I had no occasion to go to the safe again till about 12.20, when the Controller's secretary came here with a telegram to be de-coded. The safe was still locked then, but when it was opened the code was gone."

"You had had no occasion to go to the safe in the meantime?"

"None at all. I locked it at 10.20, and I unlocked it two hours later, and that was all."

"You were not in the room the whole of the time, of course?"

"Oh, no. I have told you that at 10.20 I went to the Controller's room, and after that I went out two or three times on one occasion or another. But each time I locked the door of the room."

"Oh, you did? That is important. And you took all your keys with you, I presume?"

"Yes, all. The keys on the bunch I took in my pocket, of course, and the room door key I also took. There are one or two rather important papers on my desk, you see, and anybody from the corridor might come in if the door were left unlocked."

"The lock of the door would be a good deal easier to pick than that of the safe," Hewitt observed, after examining it. "But that would be of no great use with the safe locked. Shortly, then, the facts are these. You locked the code safely away at 10.20, you left the room two or three times, but each time the door, as well as the safe, was locked, and the keys in your pocket; and then, at 12.20, or two hours exactly after the code had been put safely away, you opened the safe again in presence of the Controller's secretary, and the code had vanished. That is the whole matter in brief, I take it?"

"Precisely." Mr. Telfer was pallid and bewildered. "It seems a total impossibility," he said; "a total, absolute, physical impossibility; but there it is."

"But as no such thing as a physical impossibility ever happens," Hewitt replied calmly, "we must look further. Now, are there any other ways into this room than by that door into the corridor? I see another door here. What is that?"

"That door has been locked for ages. The room on the other side is one like this, with a door in the corridor; it is used chiefly to store old documents of no great importance, and I believe that whole stacks of them, in bundles, are piled against the other side of that same door. We will send for the key and see, if you like."

The key was sent for, and the door from the corridor opened. As Telfer had led us to expect, the place was full of old papers in bundles and parcels, thick with ancient dust, and these things were piled high against the door next his room, and plainly had not been disturbed for months, or even years.

"There remains the skylight," said Hewitt, "for I perceive, Mr. Telfer, that your room is lighted from above, and has no window; while the grate is a register. There seems to be no opening in that skylight but the revolving ventilator. Am I right?"

"Quite so. There is no getting in by the skylight without breaking it, and, as you see, it has not been broken. Certainly there are men on the roof repairing the leads, but it is plain enough that nobody has come that way. The thing is wholly inexplicable."

"At present, yes," Hewitt said, musingly. He stood for a few moments in deep thought.

"Plummer is longer away than I expected," he said presently. "By the way, what was the external appearance of the missing code?"

"It was nothing but a sort of thin manuscript book, made of a few sheets of foolscap size, sewn in a cover of thickish grey paper. I left it in the safe doubled lengthwise, and tied with tape in the middle."

"Its loss is a very serious thing, of course?"

"Oh, terribly, terribly serious, Mr. Hewitt," Telfer replied, despairingly. "I am responsible, and it will put an end to my career, of course. But the consequences to the country are more important, and they may be disastrous—enormously so. A great sum would be paid for that code on the Continent, I need hardly say."

"But now that you know it is taken, surely the code can be changed?"

"It's not so easy as it seems, Mr. Hewitt," Telfer answered, shaking his head. "It means time, and I needn't tell you that with affairs in their present state we can't afford one moment of time. Some expedients are being attempted, of course, but you will understand that any new code would have to be arranged with scattered items of the fleet in all parts of the world, and that probably with the present code in the hands of the enemy. Moreover, all our messages already sent will be accessible with very little trouble, and they contain all our strategical coaling and storing dispositions for a great war, Mr. Hewitt; and they can't, they can't be altered at a moment's notice! Oh, it is terrible!... But here is Inspector Plummer. No news, I suppose, Mr. Plummer?"

"Well, no," Plummer answered deliberately. "I can't say I've any news for you, Mr. Telfer, just yet. But I want to talk about a few things to Mr. Hewitt. Hadn't we better go and see if your telegram is answered, Mr. Hewitt? Unless you've heard."

"No, I haven't," Hewitt replied. "We'll go on at once. Good-day for the present, Mr. Telfer. I hope to bring good news when next I see you."

"I hope so, too, Mr. Hewitt, most fervently," Telfer answered; and his looks confirmed his words.

We walked in silence through the corridor, down the stairs, and out by the gates into the street. Then Plummer turned on his heel and faced Hewitt.

"That man's a wrong 'un," he said, abruptly, jerking his thumb in the direction of the office we had just left. "I'll tell you about it in the cab."

As soon as our cab was started on its way back to Hewitt's office Plummer explained himself.

"He's been watched," he said, "has Mr. Telfer, when he didn't know it; and he'll be watched again for the rest of to-day, as I've arranged. What's more, he won't be allowed to leave the office this evening till I have seen him again, or sent a message. No need to frighten him too soon—it mightn't suit us. But he's in it, alone or in company!"

"How do you know?"

"I'll tell you. It seems the lead roofs are being repaired at the Admiralty, and the plumbers are walking about where they like. Now I needn't tell you I've had a man or two fishing about among the doorkeepers and so on at the Admiralty, and one of them found a plumber he knew slightly, working on the roof. That plumber happens to be no fool—a bit smarter than the detective-constable, it seems to me, in fact. Anyhow, he seems to have got more out of my man than my man got out of him; and soon after I reached the Yard he turned up, asking to see me. He said he'd heard that a valuable paper was missing (he didn't know what) from the room with the skylight in the top floor, where the gentleman with the single eye-glass was, and where the safe was let in the wall; and he wanted to know what would be the reward for anybody giving information about it. Of course I couldn't make any promise, and I gave him to understand that he would have to leave the amount of the reward to the authorities, if his information was worth anything; also, that we were getting to work fast, and that if he wished to be first to give information he'd better be quick about it; but I promised to make a special report of his name and what he had to say if it were useful. And it will be, or I'm vastly mistaken! For just you see here. Our friend, Mr. Telfer, says he put that code safely away at 10.20 in the safe, and that he never went to the safe again till 12.20, when the Controller's secretary was with him; never went to it for anything whatever, observe. Well, the plumber happened to be near the skylight at half-past eleven, and he is prepared to swear that he saw Mr. Telfer—'the gent with the eye-glass,' as he calls him—go to the safe, unlock it, take out a grey paper, folded lengthwise, with red tape round it, re-lock the safe, and carry that paper out into the corridor! The plumber was kneeling by a brazier, it seems, which was close by the skylight, and he is so certain of the time because he was regulating his watch by Westminster Hall clock, and compared it when the half-hour struck, which was just while Telfer was absent in the corridor with the paper. He was only gone a second or two, and you will remember that Corder saw Mayes leaving the premises within two minutes of that time!"

"Yes!"

"Well, Telfer was back in a second or two, without the paper, and went on with his affairs as before. That's pretty striking, eh?"

"Yes," Hewitt answered thoughtfully, "it is."

"It was a sort of shot in the dark on the part of the plumber, for he knew nothing else—nothing about Telfer legitimately having the keys of the safe, nor any of the particulars we have been told. He merely knew that a paper was missing, and having seen a paper taken out of the safe he got it into his head that he had possibly witnessed the theft; and he kept his knowledge to himself till he could see somebody in authority. Mighty keen, too, about a reward!"

"And now you are having Telfer supervised?"

"I am. Not that we're likely to get the code from him; that's passed out, sure enough, in Mayes's hands—or else his pockets."

To this confident expression of opinion Hewitt offered no reply, and presently we alighted at his office, eager to learn if Peytral had given the information Hewitt so much desired. Sure enough a telegram was there, and it ran thus:

"Now we're at work," Hewitt said, briskly, "and for a while we part. I shall make a few changes of dress, and go to take a look at 37 Raven Street, Blackfriars. Will you two go on to Norbury Row? You'll have to be careful, Plummer, and not show yourself. That is where Brett will be useful, since he isn't known; if anybody is to be seen let it be him. I shall be very careful myself—though I shall have some little disguise; and I fancy I shall not be so likely to be seen as you."

"What are we to do?" I asked.

"Well, of course, if you see Mayes in the open, grab him instantly. I needn't tell Plummer that. I think Plummer would naturally seize him on the spot, rush him off to the nearest station and go back with enough men to clear out No. 8 Norbury Row. If you don't see him you'll keep an observation, according to Plummer's discretion. But, unless some exceptional chance occurs, I hope you won't go rushing in till we communicate with each other—we must work together, and I may have news. My instinct seems to tell me that yours is the right end of the stick, at Barbican. But we must neglect nothing, and that is why I want you to hold on there while I make the necessary examination at the other end. Do you know this Norbury Row, Plummer?"

"I think I know every street and alley in the City," Plummer answered. "There is a very good publican at the corner of Norbury Row, who's been useful to the police a score of times. He keeps his eyes open, and I shall be surprised if he can't give us some information about No. 8, anyhow. Moon's his name, and the house is 'The Compasses.' I shall go there first. And if you've any message to send, send it through him. I'll tell him."

On the stairs Plummer and I encountered another of his assistants. "I've got the cab, sir," he reported. "Waiting outside now. Took up a fare in Whitehall, opposite the Admiralty, and drove him to Charterhouse Street; got down just by the Meat Market. That's all the man seems to know."

Plummer questioned the cabman, and found that as a matter of fact that was all he did know. So, telling him to wait to take us our little journey, we returned and reported his information to Hewitt.

"Just as I expected," he said, quietly. "He stopped the cab a bit short of his destination, of course,—just as you will, no doubt. There's not a great deal in the evidence, but it confirms my idea."

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