“But what is at the root of it?”

“Ah, yes, Watson — severely practical, as usual! What is at the root of it all? Mrs. Warren’s whimsical problem enlarges somewhat and assumes a more sinister aspect as we proceed. This much we can say: that it is no ordinary love escapade. You saw the woman’s face at the sign of danger. We have heard, too, of the attack upon the landlord, which was undoubtedly meant for the lodger. These alarms, and the desperate need for secrecy, argue that the matter is one of life or death. The attack upon Mr. Warren further shows that the enemy, whoever they are, are themselves not aware of the substitution of the female lodger for the male. It is very curious and complex, Watson.”

“Why should you go further in it? What have you to gain from it?”

“What, indeed? It is art for art’s sake, Watson. I suppose when you doctored you found yourself studying cases without though{ of a fee?”

“For my education, Holmes.”

“Education never ends, Watson. It is a series of lessons with the greatest for the last. This is an instructive case. There is neither money nor credit in it, and yet one would wish to tidy it up. When dusk comes we should find ourselves one stage advanced in our investigation.”

When we returned to Mrs. Warren’s rooms, the gloom of a London winter evening had thickened into one gray curtain, a dead monotone of colour, broken only by the sharp yellow squares of the windows and the blurred haloes of the the gas-lamps. As we peered from the darkened sitting-room of the lodginghouse, one more dim light glimmered high up through the obscurity.

“Someone is moving in that room,” said Holmes in a whisper, his gaunt and eager face thrust forward to the window-pane. “Yes, I can see his shadow. There he is again! He has a candle in his hand. Now he is peering across. He wants to be sure that she is on the lookout. Now he begins to flash. Take the message also, Watson, that we may check each other. A single flash — that is A, surely. Now, then. How many did you make it? Twenty. So did I. That should mean T. AT — that’s intelligible enough! Another T. Surely this is the beginning of a second word. Now, then — TENTA. Dead stop. That can’t be all, Watson? ATTENTA gives no sense. Nor is it any better as three words AT, TEN, TA, unless T. A. are a person’s initials. There it goes again! What’s that? ATTE why, it is the same message over again. Curious, Watson, very curious! Now he is off once more! AT — why, he is repeating it for the third time. ATTENTA three times! How often will he repeat it? No, that seems to be the finish. He has withdrawn from the window. What do you make of it, Watson?”

“A cipher message, Holmes.”

My companion gave a sudden chuckle of comprehension.

“And not a very obscure cipher, Watson,” said he. “Why, of course, it is Italian! The A means that it is addressed to a woman. ‘Beware! Beware! Beware!’ How’s that, Watson?”

Under Mrs Bolton’s influence, Clifford began to take a new interest in the mines. He began to feel he belonged. A new sort of self–assertion came into him. After all, he was the real boss in Tevershall, he was really the pits. It was a new sense of power, something he had till now shrunk from with dread.

Tevershall pits were running thin. There were only two collieries: Tevershall itself, and New London. Tevershall had once been a famous mine, and had made famous money. But its best days were over. New London was never very rich, and in ordinary times just got along decently. But now times were bad, and it was pits like New London that got left.

‘There’s a lot of Tevershall men left and gone to Stacks Gate and Whiteover,’ said Mrs Bolton. ‘You’ve not seen the new works at Stacks Gate, opened after the war, have you, Sir Clifford? Oh, you must go one day, they’re something quite new: great big chemical works at the pit–head, doesn’t look a bit like a colliery. They say they get more money out of the chemical by–products than out of the coal—I forget what it is. And the grand new houses for the men, fair mansions! of course it’s brought a lot of riff–raff from all over the country. But a lot of Tevershall men got on there, and doin’ well, a lot better than our own men. They say Tevershall’s done, finished: only a question of a few more years, and it’ll have to shut down. And New London’ll go first. My word, won’t it be funny when there’s no Tevershall pit working. It’s bad enough during a strike, but my word, if it closes for good, it’ll be like the end of the world. Even when I was a girl it was the best pit in the country, and a man counted himself lucky if he could on here. Oh, there’s been some money made in Tevershall. And now the men say it’s a sinking ship, and it’s time they all got out. Doesn’t it sound awful! But of course there’s a lot as’ll never go till they have to. They don’t like these new fangled mines, such a depth, and all machinery to work them. Some of them simply dreads those iron men, as they call them, those machines for hewing the coal, where men always did it before. And they say it’s wasteful as well. But what goes in waste is saved in wages, and a lot more. It seems soon there’ll be no use for men on the face of the earth, it’ll be all machines. But they say that’s what folks said when they had to give up the old stocking frames. I can remember one or two. But my word, the more machines, the more people, that’s what it looks like! They say you can’t get the same chemicals out of Tevershall coal as you can out of Stacks Gate, and that’s funny, they’re not three miles apart. But they say so. But everybody says it’s a shame something can’t be started, to keep the men going a bit better, and employ the girls. All the girls traipsing off to Sheffield every day! My word, it would be something to talk about if Tevershall Collieries took a new lease of life, after everybody saying they’re finished, and a sinking ship, and the men ought to leave them like rats leave a sinking ship. But folks talk so much, of course there was a boom during the war. When Sir Geoffrey made a trust of himself and got the money safe for ever, somehow. So they say! But they say even the masters and the owners don’t get much out of it now. You can hardly believe it, can you! Why I always thought the pits would go on for ever and ever. Who’d have thought, when I was a girl! But New England’s shut down, so is Colwick Wood: yes, it’s fair haunting to go through that coppy and see Colwick Wood standing there deserted among the trees, and bushes growing up all over the pit–head, and the lines red rusty. It’s like death itself, a dead colliery. Why, whatever should we do if Tevershall shut down—? It doesn’t bear thinking of. Always that throng it’s been, except at strikes, and even then the fan–wheels didn’t stand, except when they fetched the ponies up. I’m sure it’s a funny world, you don’t know where you are from year to year, you really don’t.’