I was just dropping off to sleep that night when I heard a sharp rap at my door. Jumping up, I opened it, and Tom rushed in.

“I’ve just thought of something, Jim. The hinges did disappear from that blind. We struck the wrong house to-day, but we mustn’t give up on that account. Suppose you go back again to the lodging house in the morning, and see if you can get any more light.”

“Sure thing,” I answered. “But now, for heaven’s sake, let me go to sleep.”

“Of course,” said Tom, in an aggrieved tone. “But I thought you’d want to hear about that as soon as I struck it.”

“Sure thing,” I repeated again. “Only, now I know about it, go to bed, and let me do the same.” My head touched the pillow as I heard the sound of the closing door, and then I slept the clock around.

The next morning I started straight for Bloomsbury, to my destination of the morning before, the lodging house. My stout friend the landlady was out, so the maid informed me, but I could see the room again if I wished. Once on the top story, I flung open the window and gazed about me. The wilderness of brick was broken only by the waving boughs that keep this part of London from being quite the dreary waste that most modern cities are fast becoming, or have long since become. As I stood there striving to pierce the mystery, the maid stood at a shambling attention in the doorway. Finally, I turned.

“I was very much interested in the story your mistress told me of the falling shutter,” I said, slipping a half crown into her ready fingers. “I should very much like to know if any part of the old shutter is by any chance in existence.”

The maid’s eyes glistened, as she glanced surreptitiously at the coin in her hand. “Wreck’s down in t’ wash’oose,” she said.

“You’re from the Coal-pits or the Mines,” I said, smiling as I heard her dialect.

A dim flush showed in her sallow cheek. “I’m fra about there, sir. Hast ever been there? There’s none like it.”

“I’ve been there,” I answered, smiling again. “There’s some fine men there.”

Her eyes lighted once more. “Happen thou might like to see wreck? Canst, if thou wish.”

“Just what I would like,” I answered, and the maid turned and clattered down the stairs. Down in the basement, leaning against the wall beside some tubs, was the wrecked shutter. I brought it out to light. The hinges were gone. Not a bit of iron showed upon it. I turned to the silent maid.

“Queer thing where the hinges went?” I said questioningly.

“Noa,” she replied. “See t’wood-box there?”

“Yes,” I answered.

“Thot had t’hinges; Michael took them t’day t’shutter fell.”

Eagerly I bent over the rude wood-box and examined the hinges carefully, measuring them with my handkerchief, and comparing the size with the lighter spots on the shutter, which showed where the hinges had been. There could be little doubt that what the girl said was true. One doubt remained.

“Why did not your mistress know what became of the hinges?” I asked.

“T’ mistress is rarely fogged, and doan’t know many a thing goes on,” the maid explained. “But to a man thot knows t’ Coal-pits—” She did not finish, but I understood, and a second half crown lighter in purse, I walked away.

All the way home the ludicrousness of our twenty-four hour comedy of errors kept growing on me, and I startled more than one passer-by with a sudden chuckle. Tom and Dorothy sprung up in alarm as I entered and leaned against the wall, weak with laughter.

“Are you hurt, Jim?” cried Dorothy, anxiously turning towards me.

“No! No!” I gasped. “But the disappearing iron hinge of the blind belongs in the same class as the dentist’s laboratory. ‘Michael put them on t’ wood-box in t’ washoose.’ That’s where they disappeared to.”

The full beauty of the situation suddenly dawned upon Tom’s mind, and he broke into inextinguishable laughter while Dorothy, her face lighting with glee, joined in, a moment later, in silvery accord. The adventure of the two young men and the young woman who hunted the disappearing shutter of Bloomsbury ended with our mirth.

Directly after lunch we started off towards Chelsea. Up the embankment, past the Houses of Parliament and the Tate Gallery, by the broad stretches of Chelsea Hospital where a few old pensioners were sunning themselves on the trim walks, our motor car carried us to the very edges of the quaint old suburb. Our chauffeur had never heard of the street named in the clipping, and it was only after diligent search that we found the little back street, a mews, where stables and kennels alternated with houses of stablemen and farriers, where trig grooms in leggings the chrysalides, and pompous coachmen in severe livery the full grown moths, met on equal terms.

At the end of the little street stood a small public house for the benefit of the Jehus who congregated in the neighborhood. As we passed it, Tom stopped the chauffeur.

“I’ll run in here,” he said, “and see what I can find.” In ten minutes he was back.

“Have you found anything?” queried Dorothy, leaning forward.

Tom nodded. “We’ll leave the car here,” he said laconically. “Come on with me.”

Down the little street and through an inner court Tom led the way. At length he entered a gate whose rounding arch supported a quaint carved horse’s head, that might well have seen the equipages of a century or more ago lumbering beneath. Within, was a square paved courtyard; straight ahead, a boarded stable; on the right, an old farrier’s shop, whose disused bellows and forge showed through a dusty window; on the left, a slatternly dwelling. A sign on the stable and the shop stated the whole premises were to let. “Inquire on the left of the yard.”

“They told me in the pub that the sign hung over the gateway with the carved horse’s head,” said Tom. “It was called the sign of the three horses. I’m going to see if they know anything about it at the house.”

Dorothy and I waited by the gateway, while Tom crossed the yard. As he advanced, the door opened and a tall, rectangular woman came out, clothespin in mouth and a piece of washing in her hands. A somewhat one-sided conversation followed.

“I want to see the stable for rent,” said Tom.

“Um um um um,” responded the woman, from her half closed mouth.

“I beg your pardon,” said Tom, “but I don’t quite understand.”

Another mumble followed, as the woman right about faced and walked into the house. Tom cast a comical look at us.

“That’s what comes of not learning the language of the country you’re going into,” he called, in a loud aside. “I can talk German, French or Italian, read Latin and make a try at Greek, but I never studied a word of Clothespin.”

As he ended, the woman reappeared, still grasping the garment for the line, but holding out as well two ponderous iron keys. Tom took them and turned to us, simply remarking, “We’ll look the place over.”

Loft, stalls and cellar of the stable offered us nothing, nor did we get more from the windows with their view of littered yards. The old farrier’s shop looked better. Tom thrust the ponderous key into the lock and threw back the heavy door. Right where the sun cast its gleam down the dusty floor lay a little pile of painted boards. I sprang forward.

“Sliced animals,” I called to the others, as I brought the six or seven old boards forward and began fitting them into place. I had them sorted and arranged in a trice. Bruised as they were by their fall, the three horses’ heads on the sign board still showed clear, though the dimming effect of time had dulled the flaring tints of the rude artist.

“Not a nail in it or a bit of iron, though there were six nail holes to every board. This can’t be another wood-box hinge case,” I remarked.

As we all bent eagerly over the sign, a voice broke in on us. “That sign nearly cost us a pretty penny.”

We straightened up quickly. In the doorway stood a stout, red-whiskered man.

“I’m the agent for the property,” he said, “I heard you were looking it over, so I came across. We’re ready to put it in good shape for any desirable tenant. There’s few better stable properties in the Chelsea mews.”

“Really,” said Tom, “I’m not sure whether this will meet my needs or not. We’ve just been looking things over and came upon this sign. It must have received a pretty severe blow, for every screw is out of it.”

“Well, sir,” said the agent eagerly, “that’s the very strangest thing I ever saw. I saw the sign go down,—I was just across the yard here in that corner, and I happened to be looking out through the archway. There was no wind, not a breath of air stirring, and yet, all of a sudden, the old sign tumbled. A man had gone by not a minute before. It might just as well hit him as not, or hit me, for that matter. And the pole that held it, and the nails and hinges and everything must have flown out of it when it struck. Least, I don’t see what else could have happened to ’em. They weren’t there when I came along, and they were good iron, too. I looked that sign over, myself, inside of two months, to make sure things were all right.”

Our voluble friend stopped for breath. As Tom addressed him, I spoke in an aside to Dorothy.

“I always supposed years ago that the English were the most silent race on earth, but I’m finding out my mistake now. It’s the upper classes that are silent and the country people. Your Londoner can talk a blue streak, once he gets going.”

Tom had stepped out into the yard with the agent to give us a further chance to look over the sign, and we were just about to make another examination of the nail holes, when Tom sung out to us, “Come out here, will you?”

Out we came, to see the agent hurrying away and Tom, with key in hand, ready to lock up.

“I really believe we’ve got something, this time,” he said, in a low voice. “It seems this chap is an understrapper of the agent of the Duke of Moir, who owns all this property about here. He tells me that he let three rooms to a man named Cragent, who occupied them as a workshop or a laboratory off and on for some months, and left about two days ago. Sometimes he’d be gone for months at a time. The man’s gone off for the keys now. He’s going to let us go through the place. He tells me that Cragent probably made some changes, though he hasn’t been inside the place yet.”

Tom ended, the agent returned with the keys, and we followed on. Just beyond the mews on the adjoining street, the agent mounted some stairs beside a little bakeshop.

The red-whiskered man slipped a key in the lock and threw open the door. Eagerly we pressed in. The bare rooms showed some slight litter left by their former occupant, wrapping paper, broken bits of insulated wire, a shelf which showed behind it heavy disconnected wires which must have led to a motor generator, a sink with high goose neck tap.

“It was a laboratory, all right,” I said to Dorothy, who nodded and passed by into the third room. She crossed directly to the rear window.

“Look here, Jim,” she called softly.

Tom and the agent were left behind in the large centre room. I followed Dorothy’s pointing finger with my eyes, as I reached her side. There, between the buildings, showed a narrow, open strip, which ended in the shadow of a dark arch, crowned by a rudely carved horse’s head. It was the arch where the sign of the “Three Horses” had hung.

“If this was the man’s laboratory, his destructive power could have escaped from this window,” murmured Dorothy, “gone straight through, and attacked that sign, without meeting iron anywhere else on the way. Oh, Jim, do you suppose this room corresponded to Dr. Heidenmuller’s wooden room? The man might have wooden panels to the windows and a double door, and taken them down when he left.”

I shook my head. “If enough of that deadly stuff got away to destroy the iron of the sign, it would destroy every nail inside the room, and here are iron nails holding the window casing together.”

“That’s right,” said Dorothy, as she inspected the nail heads. “Those do look like iron nails.” Then she broke square off. “Got your knife in your pocket, Jim?”

Silently I produced and opened it.

“Now try to pry out that nail,” she commanded, pointing to one on the window casing.

I obeyed, with the full expectation of breaking my knife short off. To my utter surprise, the blade cut straight through the nail, with less resistance than the wood around it offered. The nail head was shorn away. Dorothy and I sprang at the same moment to pick it up, and we met in a sudden collision. Only by the extraordinary presence of mind which I showed in clasping Dorothy closely in my arms was a complete spill averted. A soft tendril of the sweet spring woods swept my cheek, the velvet petal of a flower brushed by my lips, and my whole body was aflame. Scarcely the fraction of a second was Dorothy in my arms, yet it seemed as if eons of life had passed. As we scrambled to our feet, I could feel my face blazing. I looked at Dorothy. Her face was as suffused as mine felt. Just then Tom entered and stood gazing at us with a quizzical smile. “Head on collision,” he exclaimed, in mock alarm. “Another big accident.” Not a word did Dorothy reply to his badinage. She walked in an especially stately fashion to the window and stood gazing out, while I busied myself energetically in hunting once more for the end of the nail which my knife had shorn off. It was lying just by my side, and as I picked it up, it crumbled.

“Why, these nail heads are putty,” I cried in amazement. “They’re simply imitations of nails.”

In a minute Tom’s knife was in his hand, and, quite forgetting everything else, he was hacking away at a point where another nail head showed.

“Putty on top to represent an old nail head, and wooden peg doing the business below,” he ejaculated. “I don’t believe there’s a bit of iron in the place.”

Tom dug at nail head after nail head, and each flew off. “Dorothy, it’s a wooden room,” he cried.

“Oh, really,” said Dorothy, in an entirely lifeless monotone.

“And there is the horse’s head out of that window. You must have been blind not to have seen it before.”

“We did see it,” I said testily. “But you’re so confoundedly impetuous you rush ahead before anybody can tell you anything.”

Tom paid but slight attention to my remarks. He was up on a window sill, prying with his knife. “I’ve got it,” he exclaimed finally in triumph. “Here’s the place where they hung the wooden shutters on with wooden pegs, and they painted and puttied them over when they took the panels down.”

He leaped down and started towards the other room. “I’m going to find out what the agent knows,” he called back over his shoulder.

Dorothy still stood by the window, the later afternoon sun making a golden halo of her somewhat rumpled hair. As I watched her, there seemed to be something a trace less energetic in her posture. She was leaning against the window and gazing fixedly outward. She did not notice me at all. For ten minutes we remained in a silence broken only when Tom returned, waving a dirty piece of paper triumphantly.

“The agent didn’t know where the chap had gone,” he cried, “but I’ve got a line on him, anyway. Here’s the address of a dealer in electrical supplies, left in a corner on a scrap of paper. We’ll drive straight to the city and look him up.”

Down the embankment the way we came, past the Savoy and the Temple, through Queen Victoria Street, and by the Bank to Bishopsgate Street we ran. Dorothy sat beside me on the rear seat of the car, Tom next the driver. All the way in, she gave me hardly a word, scarcely replied to Tom’s occasional chatter. I had never seen her tongue so strangely silent, her cheek so blushed with morning crimson, nor had I ever seen her eyes more deeply thoughtful, more softly beautiful.

We drew up before the supply store and Tom hurried in, followed by Dorothy and myself. He wanted some wire of the same type as that last ordered by Mr. Cragent. Could they look up the order and let him have it. Certainly. No difficulty at all. The clerk went back to examine the order book, and I followed by his side. In the little dingy office at the rear stood a high desk, with the tall books above in an ordered row. Down came C. “Cragent, Page 116,” said the index. As the clerk turned to the page, I glanced over his shoulder. “Mr. H. Cragent.” The Chelsea address was crossed out with a line; written below were the words, “9 Cheapside.” That was all I wanted. I nodded to Tom, as he gave a hurried order for the wire, and we were free for the new address.

“This is the right one,” said Dorothy quietly, as we left the shop.

“How do you know?” asked Tom. “It looks good, I’ll admit, but I don’t see how you can tell.”

“I don’t know how I can tell,” answered Dorothy, in low tones, “but I feel sure, this time, as I haven’t before.”

In ten minutes we were at the corner nearest to the new address, had left the car, and were walking up the busy street.

The sign above the door at 9 Cheapside proclaimed a haberdasher’s shop within. The second story showed a dealer in notions, and the third and fourth held no signs.

“There are leads from the power circuit running into the fourth story,” said Tom, as we passed. “Here’s the door. No business cards for anything above the second. Come on, let’s try next door.”

Up the stairs by a milliner’s shop, past the third story, to the fourth, we climbed. A wing ran back, with a gallery that opened on one side. At the rear was a short flight of steps, with a scuttle at the top, which opened out on the roof. By good fortune, this was unlocked, and we climbed through, out on the flat roof, into the maze of chimneys. Tom was a little ahead and reached the parapet on the side of Number 9, while we were still at the scuttle. As he turned to the edge, he wheeled and beckoned to us expressively. We hurried forward. Below, on the fourth story, three shuttered windows faced us. In the centre one, the wind had blown half the blind open. Behind it, we gazed on a solid wooden panel, which filled the window from top to bottom, from side to side, behind the glass.

“An exact duplicate of the window panels of Heidenmuller’s wooden room,” I whispered. Tom and Dorothy nodded silently.