"Not Myatt?" I said. "After the chase--"

"No, not Myatt."

"Catherton Hunt?"

"No, nor Catherton Hunt. He had opened it in the name of Mayes!"

"What! his actual name?"

"His actual original name, according to Peytral. The account was transferred, it would seem, from another bank; and I have an idea we may find that he has been shifting his money about from one bank to another as safety suggested, using his real name with it. You remember we could find no trace of a banking account when the police raided and ransacked Calton Lodge after Mason was killed? Quite probably he has had small current accounts in other names at various times to aid in his schemes, but his main account has always stood in his real name; and by that, you see, we get some confirmation of Peytral's story. Well, as I say, the account was opened in the name of Mayes, and the cheque-book was issued which we discovered last night. The Upper Holloway branch saw no more of its customer till yesterday evening, long after hours, when he drove up in a hansom."

"Oh," I said, "in a hansom, was it? The men left behind could get no news of him."

"Yes, we ascertained that last night; we called back, of course, the last thing. I expect he got the first cab visible and drove off to a hatter's a fair distance away, and then on to the bank. At any rate, he knocked up the manager and told him that he had a sudden need for money that very night; could he have some?

"The manager told him it would be impossible. Even if he had been willing to do it, against all regulations, it would still be impossible. For the strong-room and every cash receptacle in it was locked with two separate locks with different keys, and though he had one of these keys himself, it was useless without the other, which was in the possession of his second in command, who lived some distance out of London. This course is the usual precaution adopted in branch banks of this sort; opening and closing, morning and evening, have to be done by chief and a.s.sistant together. And I tell you, Brett, I believe that it was only the being informed of this fact that prevented Mayes from trying some of his hypnotic tricks on the bank manager; in which case there would have been a big bank robbery-perhaps something worse in addition."

"Murder?"

"Murder with a tourniquet, perhaps-perhaps with some other weapon; but, at any rate, probably with the Red Triangle. You know, of course-indeed I told you, I think-that in most cases-not all-it is necessary to get the subject's consent to the first exercise of hypnotism on him. I told you also it is possible for the practised hypnotist, while the subject is under the influence of the first experiment, to suggest to him a certain word or formula, or even a silent sign, which shall bring him under the influence at any other time, whenever the hypnotist chooses to repeat it-just as must have been done with Mr. Telfer, in the case of the Admiralty code. The first suggestion would not be the difficult thing it might seem-it would only require a little time and persuasion. Nothing would be said about hypnotism, of course; perhaps something about a little physical experiment, or the like, and then in a moment or two the subject would be in this creature's power for ever. Remember the little 'ceremony of initiation' that the scoundrel attempted to persuade you to submit to! That meant hypnotism-perhaps death.

"But this is mere speculation. Mayes found that the keys on the premises were not enough to release his money, even if the strict rules of the bank had permitted the cashing of a cheque out of hours. But the manager suggested that perhaps some neighbouring tradesman would exchange cash for a cheque, and, with the view of obliging the new customer, went with him as far as the shop of Mr. Isaac Trenaman, a grocer and cheesemonger with a rather large shop at the corner of the road. Mr. Trenaman, introduced and a.s.sured by the manager, was willing to give as much cash as he could find in the till against Mr. Mayes's cheque, and did so to the extent of twenty-seven pounds, a cheque for which sum was duly drawn on one of the tradesman's own cheque forms, and left with him. This done, the bank's new customer took himself off, with thanks and apologies; carrying with him, however, two blank cheque forms from Mr. Trenaman's book, the pennies for which he punctiliously paid over the counter. Having no cheque forms with him, he explained, he might find them useful if he could come across some friend who could provide the cash he wished to use that night. And having completed this business so far, this charming new customer of the bank made off into the night."

"And is that all you know of his movements?"

"Yes, as yet. He seems to have made no very definite excuse to the manager for wanting the money in such a hurry-just said something had occurred which made cash necessary, and was very polite and apologetic, generally. The manager formed a notion that it must be for some gambling purpose-he fancied that Mayes said something distantly alluding to that, but wasn't sure."

"Did you ask about the address given to the bank?"

"Of course; but there we gained nothing. The manager couldn't remember it exactly, and the books, of course, were locked up. But we know it already-for what the manager could remember was that it was an office address, and somewhere near Barbican! So that we are back at the Barbican den again, where I am going now, with Plummer, to give a day to a minute investigation of the whole place. Meanwhile a watch is being set at the bank in Holloway."

"Do you expect him back there, then?"

"Hardly. You see he knows that by this time we must have found his cheque-book, and will be on the watch. But there is just a chance-a very remote one-that he may send a message; perhaps send somebody to cash a cheque. Though I don't expect it, for he is no fool-he is, indeed, a sort of genius-and that would be a mistake, I think. Still, he is bold, and that is where his money is, and he may make a dash at it. So a couple of Plummer's men are to be waiting there, this morning, in the manager's office, and if anybody comes from Mayes he will be detained. Perhaps you would like to be with them? You can't be of much use with me, and the job will be dull. But there you may have a chance of excitement, and you will be useful to come and report if anything does happen. Why, you may even bag Mayes himself!"

"Of course-I'll go anywhere you please. They told you last night, I suppose, that Peytral had business, and had gone off?"

"Yes, and I'm not sorry. He is too dangerous a man to have about us, with his hot blood and the terrible injuries he keeps in memory. As likely as not, if we get Mayes, we should next have to collar Peytral for shooting him, or something. So I'm not sorry he is out of it for a bit. But can you start now? Plummer is in my office and the two men are in a cab outside. The bank opens at nine, and that is in Upper Holloway."

I seized my hat and made ready.

"You should keep your eyes open," Hewitt hinted, "before you get to the bank and when you leave, as well as while you're there. Do you remember how poor Mason was watched? Well, there is probably some watching going on now. Last night, on our way to the bank and back, I believe Plummer and I were watched pretty closely."

III

Plummer's two plain-clothes men and I reached the neighbourhood of the bank with a quarter of an hour to spare, or rather more. We dismissed the cab at some little distance from the spot, and approached singly, so that it was not difficult for us to slip in separately among the dozen or fifteen clerks as they arrived. We pa.s.sed directly into the manager's room, the door of which opened into the s.p.a.ce left for the public before the counter. From this room the whole of the outer office was visible through the gla.s.s of the part.i.tion. The manager, Mr. Blockley, a quick, intelligent man of thirty-six or so, gave us chairs and pointed out how best we could watch the counter without ourselves being observed.

"If a letter is sent," he said, "it will be brought here to me, of course, and I will bring the messenger in. If a cheque is presented from Mayes, I have told the cashier to slide that big ledger off his desk accidentally with his elbow. That will be your signal, and then you can do whatever you think proper. I don't think I can do any more than that."

We took our positions and waited. I felt pretty sure that if Mayes sent at all it would be early, for obvious reasons. And I was right, for the very first customer was our man.

He stepped in briskly scarcely a minute after the manager had ceased speaking, and I remembered having seen him waiting at the street corner as I came along. He was a well-dressed, smart enough looking man, in frock coat and tall hat. He took a letter-case from his pocket, picked out a cheque from the rest of the papers in it, and pa.s.sed it under the wire grille of the counter.

The cashier took it, turned it over, and shifted mechanically to post the amount in the book on his desk. As he did so his elbow touched the heavy ledger which the manager had pointed out to us, and it fell with a crash. The cashier calmly put his pen behind his ear, and stooped to pick up the book, but even as he did it the two Scotland Yard men were out before the counter, and had sidled up to the stranger, one on each side.

"May we see that cheque, if you please?" asked one, and the cashier turned its face toward him. "Ah, just so; a hundred pounds-Mayes. We must just trouble you to come with us, if you please. There is some explanation wanted about that cheque."

I had followed the two men from the manager's room, and now I saw that while one had laid his hand on the stranger's shoulder the other had taken him by the opposite arm. "Why," said the former, looking into his face, "it's Broady Sims!"

"All right," the man growled resignedly. "It's a cop. I'll go quiet."

But as he spoke I saw the free hand steal out behind him and pitch away a crumpled fragment of paper. One of the policemen saw it too, followed it with his eyes, and saw me s.n.a.t.c.h it up.

"That's right, sir," he said, "take care of that; and we'll have a cab, in case anything else drops accidentally. It's just a turning over, Broady, that's what it is."

I spread out the piece of paper, and was astonished to find inscribed on it just such another series of figures, in groups of eight, as was found in the cypher message in the Case of the Lever Key.

Here was a great find-a secret message as clear to me as to Mayes himself, and as likely as not the sc.r.a.p of paper that would hang him! I took one of the plain-clothes men aside while the other kept his hold of Broady Sims.

"This is very important," I said. "It is a cypher message which Mr. Hewitt can read-or I, myself, in fact, with a little time. Must you take it with you? If so, I'll make a copy now."

"Well, sir, we're responsible, you see," the man said, "so I think we must take it; so perhaps you'd better make a copy, as you suggest."

"Very well," I said, "that is done in a few seconds. You can take your man off, and I will go direct to Mr. Hewitt and Inspector Plummer with the copy." And with that I made the copy, which read thus:-

23, 19, 15, 1, 9, 14, 9, 2; 20, 8, 1, 20, 14, 14, 20, 8; 14, 5, 12, 4, 9, 7, 5, 14; 3, 8, 18, 23, 0, 14, 1, 8; 22, 9, 6, 1, 18, 3, 5, 1; 19, 14, 15, 21, 9, 0, 20, 12; 18, 12, 21, 1, 6, 23, 20, 12; 9, 18, 15, 5, 18, 13, 12, 20.

It struck me to ask the manager if the cheque just presented were one of those procured from Mr. Trenaman the night before, and I found that it was. Then I left the policemen with their prisoner and made for the nearest cab-rank. This cypher message, no doubt conveying Mayes's instructions to the man just captured, was probably of the utmost importance, and Hewitt must see it at once; and as the cab ambled along towards Barbican I busied myself in deciphering the figures according to the plan of the knight's move in chess, as Hewitt had explained to me. I could only see two noughts among the numbers, so plainly it was a longer message than the one then deciphered-one of sixty-two letters, in fact. I turned the figures into the letters corresponding in the alphabet, a for 1, b for 2, and so on, as Hewitt had done, and I arranged these letters in the squares of a roughly drawn chessboard, so that they stood thus:-

ws o a i n i b th a t n n t h ne l d i g e n ch r w o n a h vi f a r c e a sn o u i o t l rl u a f w t l ir o e r m l t The letters thus set out, to read off the message was a simple task enough, in view of the key Hewitt had given me. I began, as in the case of the Lever Key message, at the right-hand top corner, and taking the knight's move from b to e in the last square but one of the third line, thence to a at the end of the fifth line, and so to t in the seventh line, and from that to r (fifth square in bottom line), u in seventh line and so on, in the order shown by the Lever Key message, a copy of which I kept as a curiosity in my pocket-book. So I read the message through, and I set it down thus:-

Be at ruin Channel Marsh to-night twelve; wait in hall for instruc. Word final.

The general meaning of this seemed clear enough. The man whom the policeman had recognised as Broady Sims was to be at some spot-a ruined building, it would seem-in a place called Channel Marsh, at midnight, there to wait in the hall for instructions; no doubt for instructions where to take the hundred pounds he was to have got from the bank. "Word final" was not so clear, though I judged-and I think rightly-that it meant that the word "final" was to be used as a pa.s.sword by which the two messengers should know each other.

I was almost at my destination, and was cogitating the message and its meaning, when the cab checked at some traffic in Barbican, just by the "Compa.s.ses" public-house, and Mr. Victor Peytral hailed me and climbed on the step of the cab.

"I was just going to see if Mr. Hewitt was at the place," he said, "and if so to ask him for news. But I am rather in a hurry, and perhaps you can tell me?"

"We are on the track, I think," I answered, "and I have just come across this, which I am taking to Hewitt," and with that I showed him my translation of the cypher, and gave him its history in half a dozen sentences.

"That's good," Peytral answered. "I don't know Channel Marsh, do you? But probably Mr. Hewitt does. I won't keep you any longer-I see you're hurrying. But I hope to see you again before long."

He dropped off the step and disappeared, and the cab went on round the corner by the "Compa.s.ses."

I found Hewitt and Plummer in the office where, on pretence of bookbindery, I had first seen Mayes face to face the day before. They were near the completion of their examination of this office and all its contents, and soon would begin as systematically on the premises behind. I gave Hewitt my copy of the cypher message, and my translation, with an exact account of how it had come into my possession.

Martin Hewitt studied the message for a minute or two, and then relapsed into grave thought. So he sat for some little time, while Plummer left the room by the window and descended the ladder to speak with his men on guard below.