Do you suppose he really had the dagger, or was that a lie?" I asked, with an effort shaking off the fateful feeling that had come over me as if some one were casting a spell.

"There is one way to find out," returned Craig, as though glad of the suggestion.

Though they hated him, they seemed forced to admit, for the time, his leadership. He rose and the rest followed as he went into Whitney's library.

He switched on the lights. There in a corner back of the desk stood a safe. Somehow or other it seemed to defy us, even though its master was gone. I looked at it a moment. It was a most powerful affair, companion to that in the office of which Whitney was so proud, built of layer on layer of chrome steel, with a door that was air tight and soup-proof, bidding defiance to all yeggmen and petermen.

Lockwood fingered the combination hopelessly. There were some millions of combinations and permutations that only a mathematician could calculate. Only one was any good. That one was locked in the mind of the man who now seemed to baffle us as did his strong-box.

I placed my hand on the cold, defiant surface. It would take hours to drill a safe like that, and even then it might turn the points of the drills. Explosives might sooner wreck the house and bring it down over the head of the man who attacked this monster.

"What can we do?" asked Senora de Moche, seeming to mock us, as though the safe itself were an inhuman thing that blocked our path.

"Do?" repeated Kennedy decisively, "I'll show you what we can do. If Lockwood will drive me down to the railroad station in his car, I'll show you something that looks like action. Will you do it?"

The request was more like a command. Lockwood said nothing, but moved toward the porte-cochere, where he had left his car parked just aside from the broad driveway.

"Walter, you will stay here," ordered Kennedy. "Let no one leave. If any one comes, don't let him get away. We shan't be gone long."

I sat awkwardly enough, scarcely speaking a word, as Kennedy dashed down to the railroad station. Neither Alfonso nor his mother betrayed either by word or action a hint of what was passing in their minds. Somehow, though I did not understand it, I felt that Lockwood might square himself. But I could not help feeling that these two might very possibly be at the bottom of almost anything.

It was with some relief that I heard the car approaching again. I had no idea what Kennedy was after, whether it was dynamite or whether he contemplated a trip to New York. I was surprised to see him, with Lockwood, hurrying up the steps to the porch, each with a huge tank studded with bolts like a boiler.

"There," ordered Craig, "set the oxygen there," as he placed his own tank on the opposite side. "That watchman thought I was bluffing when I said I'd get an order from the company, if I had to wake up the president of the road. It was too good a chance to miss. One doesn't find such a complete outfit ready to hand every day."

Out of the tanks stout tubes led, with stop-cocks and gauges at the top. From a case under his arm Kennedy produced a curious arrangement like a huge hook, with a curved neck and a sharp beak. Really it consisted of two metal tubes which ran into a sort of cylinder, or mixing chamber, above the nozzle, while parallel to them ran a third separate tube with a second nozzle of its own.

Quickly he joined the ends of the tubes from the tanks to the metal hook, the oxygen tank being joined to two of the tubes of the hook, and the second tank being joined to the other. With a match he touched the nozzle gingerly. Instantly a hissing, spitting noise followed, and an intense, blinding needle of flame.

"Now we'll see what an oxyacetylene blow-pipe will do to you, old stick-in-the-mud," cried Kennedy, as he advanced toward the safe, addressing it as though it had been a thing of life that stood in his way. "I think this will make short work of you."

Almost as he said it, the steel beneath the blow-pipe became incandescent. For some time he laboured to get a starting-point for the flame of the high-pressure torch.

It was a brilliant sight. The terrific heat from the first nozzle caused the metal to glow under the torch as if in an open-hearth furnace. From the second nozzle issued a stream of oxygen, under which the hot metal of the door was completely consumed.

The force of the blast, as the compressed oxygen and acetylene were expelled, carried a fine spray of the disintegrated metal visibly before it. And yet it was not a big hole that it made—scarcely an eighth of an inch wide, but clean and sharp as if a buzz-saw were eating its way through a plank of white-pine.

With tense muscles Kennedy held this terrific engine of destruction and moved it as easily as if it had been a mere pencil of light. He was the calmest of all of us as we crowded about him, but at a respectful distance.

"I suppose you know," he remarked hastily, never pausing for a moment in his work, "that acetylene is composed of carbon and hydrogen. As it burns at the end of the nozzle it is broken into carbon and hydrogen—the carbon gives the high temperature and the hydrogen forms a cone that protects the end of the blow-pipe from being itself burnt up."

"But isn't it dangerous?" I asked, amazed at the skill with which he handled the blow-pipe.

"Not particularly—when you know how to do it. In that tank is a porous asbestos packing saturated with acetone, under pressure. Thus they carry acetylene safely, for it is dissolved and the possibility of explosion is minimized.

"This mixing chamber, by which I am holding the torch, where the oxygen and acetylene mix, is also designed in such a way as to prevent a flash-back. The best thing about this style of blow-pipe is the ease with which it can be transported and the curious purposes—like this—to which it can be put."

He paused a moment to test what had been burnt. The rest of the safe seemed as firm as ever.

"Humph!" I heard one of them, I think it was Alfonso, mutter. I resented it, but Kennedy affected not to hear.

"When I shut off the oxygen in this second jet," he resumed, "you see the torch merely heats the steel. I can get a heat of approximately sixty-three hundred degrees Fahrenheit, and the flame will exert a pressure of fifty pounds to the square inch."

"Wonderful!" exclaimed Lockwood, who had not heard the suppressed disapproval of Alfonso, and was watching, in undisguised admiration at the thing itself, regardless of consequences. "Kennedy, how did you ever think of such a thing?"

"Why, it's used for welding, you know," answered Craig, as he continued to work calmly in the growing excitement. "I first saw it in actual use in mending a cracked cylinder in an automobile. The cylinder was repaired without being taken out at all. I've seen it weld new teeth and build up worn teeth on gearing, as good as new."

He paused to let us see the terrifically heated metal under the flame.

"You remember when we were talking to the watchman down there at the station, Walter?" he asked. "I saw this thing in that complete little shop of theirs. It interested me. See. I turn on the oxygen now in the second nozzle. The blow-pipe is no longer an instrument for joining metals together, but for cutting them asunder.

"The steel burns just as you, perhaps, have seen a watch-spring burn in a jar of oxygen. Steel, hard or soft, tempered, annealed, chrome, or Harveyized, it all burns just about as fast, and just about as easily under this torch. And it's cheap, too. This attack—aside from what it costs to the safe—may amount to a couple of dollars as far as the blow-pipe is concerned—quite a difference from the thousands of dollars' loss that would follow an attempt to blow a safe like this one."

We had nothing to say. We stood in awe-struck amazement as the torch slowly, inexorably traced a thin line along the edge of the combination.

Minute after minute sped by, as the line burned by the blow-pipe cut around the lock. It seemed hours, but really it was minutes. I wondered when he would have cut about the whole lock. He was cutting clear through and around it, severing it as if with a superhuman knife.

With something more than half his work done, he paused a moment to rest.

"Walter," he directed, mopping his forehead, for it was real work directing that flaming knife, "get New York on the wire. See if O'Connor is at his office. If he has any report, I want to talk to him."

It was getting late and the service was slackening up. I had some trouble, especially in getting a good connection, but at last I got headquarters and was overjoyed to hear O'Connor's bluff, Irish voice boom back at me.

"Hello, Jameson," he called. "Where on earth are you? I've been trying to get hold of Kennedy for a couple of hours. Rockledge? Well, is Kennedy there? Put him on, will you?"

I called Craig and, as I did so, my curiosity got the better of me and I sought out an extension of the wire in a den across the hall from the library, where I could listen in on what was said.

"Hello, O'Connor," answered Craig. "Anything from Burke yet?"

"Yes," came back the welcome news. "I think he has a clue. We found out from here that she received a long distance message during the afternoon. Where did Jameson say you were—Rockledge?—that's the place. Of course we don't know what the message was, but anyhow she went out to meet some one right after that. The time corresponds with what the maid says."

"Anything else?" asked Craig. "Have you found any one who saw her?"

"Yes. I think she went over to your laboratory. But you were out."

"Confound it!" interrupted Craig.

"Some one saw a woman there."

"It wasn't the maid?"

"No, this was earlier—in the afternoon. She left and walked across the campus to the Museum."

"Oh, by the way, any word of Norton?"

"I'm coming to that. She inquired for Norton. The curator has given a good description. But he was out—hadn't been there for some time. She seemed to be very much upset over something. She went away. After that we've lost her."

"Not another trace?"

"Wait a minute. We had this Rockledge call to work on. So we started backward on that. It was Whitney's place, I found out. We could locate the car at the start and at the finish. He left the Prince Edward Albert and went up there first. Then he must have come back to the city again. No one at the hotel saw him the second time.

"What then?" hastened Craig.

"She may have met him somewhere, though it's not likely she had any intention of going away. All the rest of those people you have up there seem to have gone prepared. We got something on each of them. Also you'll be interested to know I've got a report of your own doings. It was right, Kennedy, I don't blame you. I'd have done the same with Burke on the job. How are you making out? What? You're cracking a crib? With what?"

O'Connor whistled as Kennedy related the story of the blow-pipe. "I think you're on the right track," he commended. "There's nothing to show it, but I believe Whitney told her something that changed her mind about going up there. Probably met her in some tea room, although we can't find anything from the tea rooms. Anyhow, Burke's out trailing along the road from New York to Rockledge and I'm getting reports from him whenever he hits a telephone."

"I wish you'd ask him to call me, here, if he gets anything."

"Sure I will. The last call was from the Chateau Rouge,—that's about halfway. There was a car with a man and a woman who answers her description. Then, there was another car, too."

"Another car?"

"Yes—that's where Norton crosses the trail again. We searched his apartment. It was upset—like Whitney's. I haven't finished with that. But we have a list of all the private hacking places. I've located one that hired a car to a man answering Norton's description. I think he's on the trail. That's what I meant by another car."

"What's he doing?"

"Maybe he has a hunch. I'm getting superstitious about this case. You know Luis de Mendoza has thirteen letters in it. Leslie told me something about a threat he had—a curse. You better look out for those two greasers you have up there. They may have another knife for you."

Kennedy glanced over at the de Moches, not in fear but in amusement at what they would think if they could hear O'Connor's uncultured opinion.

"All right, O'Connor," said Craig, "everything seems to be going as well as we can expect. Don't forget to tell Burke I'm here."

"I won't. Just a minute. He's on another wire for me."

Kennedy waited impatiently. He wanted to finish his job on the safe before some one came walking in and stopped it, yet there was always a chance that Burke might turn up something.

"Hello," called O'Connor a few minutes later. "He's still following the two cars. He thinks the one with the woman in it is Whitney's, all right. But they've got off the main road. They must think they're being followed.

"Or else have changed their destination," returned Craig. "Tell him that. Maybe Whitney had no intention of coming up here. He may have done this thing just to throw these people off up here, too. I can't say. I can tell better whether he intended to come back after I've got this safe open. I'll let you know."

Kennedy rang off.

"Any news of Inez?" asked Lockwood who had been fuming with impatience.

"She's probably on her way up here," returned Craig briefly, taking up the blow-pipe again.

Alfonso remained silent. The Senora could scarcely hide her excitement. If there were anything in telepathy, I am sure that she read everything that was said over the wire.

Quickly Craig resumed his work, biting through the solid steel as if it had been mere pasteboard, the blow-pipe showering on each side a brilliant spray of sparks, a gaudy, pyrotechnic display.

Suddenly, with a quick motion, Kennedy turned off the acetylene and oxygen. The last bolt had been severed, the lock was useless. A gentle push of the hand, and he swung the once impregnable door on its delicately poised hinges as easily as if he had merely said, "Open sesame."

Craig reached in and pulled open a steel drawer directly in front of him.

There in the shadow lay the dagger—with its incalculably valuable secret, a poor, unattractive piece of metal, but with a fascination such as no other object, I had ever seen, possessed.

There was a sudden cry. The Senora had darted ahead, as if to clasp its handle and unloose the murderous blade that nestled in its three-sided sheath.

Before she could reach it, Kennedy had seized her hand in his iron grasp, while with the other he picked up the dagger.

They stood there gazing into each other's eyes.

Then the Senora burst into a hysterical laugh.

"The curse is on all who possess it!"

"Thank you," smiled Kennedy quietly, releasing her wrist as he dropped the dagger into his pocket, "I am only the trustee."