Pugh came into my room holding something wrapped in a piece of brown paper.

"Tress, I have brought you something on which you may exercise your ingenuity." He began, with exasperating deliberation, to untie the string which bound his parcel; he is one of those persons who would not cut a knot to save their lives. The process occupied him the better part of a quarter of an hour. Then he held out the contents of the paper.

"What do you think of that?" he asked. I thought nothing of it, and I told him so. "I was prepared for that confession. I have noticed, Tress, that you generally do think nothing of an article which really deserves the attention of a truly thoughtful mind. Possibly, as you think so little of it, you will be able to solve the puzzle."

I took what he held out to me. It was an oblong box, perhaps seven inches long by three inches broad.

"Where's the puzzle?" I asked.

"If you will examine the lid of the box, you will see."

I turned it over and over; it was difficult to see which was the lid. Then I perceived that on one side were printed these words:

"PUZZLE: TO OPEN THE BOX"

The words were so faintly printed that it was not surprising that I had not noticed them at first. Pugh explained.

"I observed that box on a tray outside a second-hand furniture shop. It struck my eye. I took it up. I examined it. I inquired of the proprietor of the shop in what the puzzle lay. He replied that that was more than he could tell me. He himself had made several attempts to open the box, and all of them had failed. I purchased it. I took it home. I have tried, and I have failed. I am aware, Tress, of how you pride yourself upon your ingenuity. I cannot doubt that, if you try, you will not fail."

While Pugh was prosing, I was examining the box. It was at least well made. It weighed certainly under two ounces. I struck it with my knuckles; it sounded hollow. There was no hinge; nothing of any kind to show that it ever had been opened, or, for the matter of that, that it ever could be opened. The more I examined the thing, the more it whetted my curiosity. That it could be opened, and in some ingenious manner, I made no doubt—but how?

The box was not a new one. At a rough guess I should say that it had been a box for a good half century; there were certain signs of age about it which could not escape a practiced eye. Had it remained unopened all that time? When opened, what would be found inside? It sounded hollow; probably nothing at all—who could tell?

It was formed of small pieces of inlaid wood. Several woods had been used; some of them were strange to me. They were of different colors; it was pretty obvious that they must all of them have been hard woods. The pieces were of various shapes—hexagonal, octagonal, triangular, square, oblong, and even circular. The process of inlaying them had been beautifully done. So nicely had the parts been joined that the lines of meeting were difficult to discover with the naked eye; they had been joined solid, so to speak. It was an excellent example of marquetry. I had been over-hasty in my deprecation; I owed as much to Pugh.

"This box of yours is better worth looking at than I first supposed. Is it to be sold?"

"No, it is not to be sold. Nor"—he "fixed" me with his spectacles—"is it to be given away. I have brought it to you for the simple purpose of ascertaining if you have ingenuity enough to open it."

"I will engage to open it in two seconds—with a hammer."

"I dare say. I will open it with a hammer. The thing is to open it without."

"Let me see." I began, with the aid of a microscope, to examine the box more closely. "I will give you one piece of information, Pugh. Unless I am mistaken, the secret lies in one of these little pieces of inlaid wood. You push it, or you press it, or something, and the whole affair flies open."

"Such was my own first conviction. I am not so sure of it now. I have pressed every separate piece of wood; I have tried to move each piece in every direction. No result has followed. My theory was a hidden spring."

"But there must be a hidden spring of some sort, unless you are to open it by a mere exercise of force. I suppose the box is empty."

"I thought it was at first, but now I am not so sure of that either. It all depends on the position in which you hold it. Hold it in this position—like this—close to your ear. Have you a small hammer?" I took a small hammer. "Tap it softly, with the hammer. Don't you notice a sort of reverberation within?"

Pugh was right, there certainly was something within; something which seemed to echo back my tapping, almost as if it were a living thing. I mentioned this to Pugh.

"But you don't think that there is something alive inside the box? There can't be. The box must be air-tight, probably as much air-tight as an exhausted receiver."

"How do we know that? How can we tell that no minute interstices have been left for the express purpose of ventilation?" I continued tapping with the hammer. I noticed one peculiarity, that it was only when I held the box in a particular position, and tapped at a certain spot, there came the answering taps from within. "I tell you what it is, Pugh, what I hear is the reverberation of some machinery."

"Do you think so?"

"I'm sure of it."

"Give the box to me." Pugh put the box to his ear. He tapped. "It sounds to me like the echoing tick, tick of some great beetle; like the sort of noise which a deathwatch makes, you know."

Trust Pugh to find a remarkable explanation for a simple fact; if the explanation leans toward the supernatural, so much the more satisfactory to Pugh. I knew better.

"The sound which you hear is merely the throbbing or the trembling of the mechanism with which it is intended that the box should be opened. The mechanism is placed just where you are tapping it with the hammer. Every tap causes it to jar."

"It sounds to me like the ticking of a deathwatch. However, on such subjects, Tress, I know what you are."

"My dear Pugh, give it an extra hard tap, and you will see."

He gave it an extra hard tap. The moment he had done so, he started.

"I've done it now."

"What have you done?"

"Broken something, I fancy." He listened intently, with his ear to the box. "No—it seems all right. And yet I could have sworn I had damaged something; I heard it smash."

"Give me the box." He gave it me. In my turn, I listened. I shook the box. Pugh must have been mistaken. Nothing rattled; there was not a sound; the box was as empty as before. I gave a smart tap with the hammer, as Pugh had done. Then there certainly was a curious sound. To my ear, it sounded like the smashing of glass. "I wonder if there is anything fragile inside your precious puzzle, Pugh, and, if so, if we are shivering it by degrees?"