As he did so he pa.s.sed a Mexican attired in brilliant native costume.

At a sign from Del Mar he paused and received a small package which Del Mar slipped to him, then pa.s.sed on as though nothing had happened. The keen eyes of the gray friar, however, had caught the little action and he quietly slipped out after the Mexican bolero.

Just then the domino girl hurried into the conservatory. "What's doing?" she asked eagerly.

"Keep close to me," whispered Del Mar, as she nodded and they left the conservatory, not apparently together.

Up-stairs, away from the gayety of the ballroom, the bolero made his way until he came to Elaine's room, dimly lighted. With a quick glance about, he entered cautiously, closed the door, and approached a closet which he opened. There was a safe built into the wall.

As he stooped over, the man unwrapped the package Del Mar had handed him and took out a curious little instrument. Inside was a dry battery and a most peculiar instrument, something like a little flat telephone transmitter, yet attached by wires to ear-pieces that fitted over the head after the manner of those of a wireless detector.

He adjusted the head-piece and held the flat instrument against the safe, close to the combination which he began to turn slowly. It was a burglar's microphone, used for picking combination locks. As the combination turned, a slight sound was made when the proper number came opposite the working point. Imperceptible ordinarily to even the most sensitive ear, to an ear trained it was comparatively easy to recognize the fall of the tumblers over this microphone.

As he worked, the door behind him opened softly and the gray friar entered, closing it and moving noiselessly over back of the shelter of a big mahogany high-boy, around which he could watch.

At last the safe was opened. Rapidly the man went through its contents.

"Confound it!" he muttered. "She didn't put it here--anyhow."

The bolero started to close the safe when he heard a noise in the room and looked cautiously back of him. Del Mar himself, followed by the domino girl, entered.

"I've opened it," whispered the emissary stepping out of the closet and meeting them, "but I can't find the--"

"Hands up--all of you!"

They turned in time to see the gray friar's gun yawning at them. Most politely he lined them up. Still holding his gun ready, he lifted up the mask of the domino girl.

"So--it's you," he grunted.

He was about to lift the mask of the Mexican, when the bolero leaped at him. Del Mar piled in. But sounds down-stairs alarmed them and the emissary, released, fled quickly with the girl. The gray friar, however, kept his hold on Mephistopheles, as if he had been wrestling with a veritable devil.

Down in the hall, I had again met my domino girl, a few minutes after I had resigned Elaine to another of her numerous admirers.

"I thought you deserted me," I said, somewhat piqued.

"You deserted me," she parried, nervously. "However, I'll forgive you if you'll get me an ice."

I hastened to do so. But no sooner had I gone than Del Mar stalked through the hall and went up-stairs. My domino girl was watching for him, and followed.

When I returned with the ice, I looked about, but she was gone. It was scarcely a moment later, however, that I saw her hurry down-stairs, accompanied by the Mexican bolero. I stepped forward to speak to her, but she almost ran past me without a word.

"A nut," I remarked under my breath, pushing back my mask.

I started to eat the ice myself, when, a moment later, Elaine pa.s.sed through the hall with a Spanish cavalier.

"Oh, Walter, here you are," she laughed. "I've been looking all over for you. Thank you very much, sire," she bowed with mock civility to the cavalier. "It was only one dance, you know. Please let me talk to Boum-Boum."

The cavalier bowed reluctantly and left us.

"What are you doing here alone?" she asked, taking off her own mask.

"How warm it is."

Before I could reply, I heard some one coming down-stairs back of me, but not in time to turn.

"Elaine's dressing-table," a voice whispered in my ear.

I turned suddenly. It was the gray friar. Before I could even reach out to grasp his robe, he was gone.

"Another nut!" I exclaimed involuntarily.

"Why, what did he say?" asked Elaine.

"Something about your dressing-table."

"My dressing-table?" she repeated.

We ran quickly up the steps. Elaine's room showed every evidence of having been the scene of a struggle, as she went over to the table.

There she picked up a rose and under it a piece of paper on which were some words printed with pencil roughly.

"Look," she cried, as I read with her:

Do honest a.s.sistants search safes?

Let no one see this but Jameson.

"What does it mean?" I asked.

"My safe!" she cried moving to a closet. As she opened the door, imagine our surprise at seeing Del Mar lying on the floor, bound and gagged before the open safe. "Get my scissors on the dresser," cried Elaine.

I did so, hastily cutting the cords that bound Del Mar.

"What does it all mean?" asked Elaine as he rose and stretched himself.

Still clutching his throat, as if it hurt, Del Mar choked, "I found a man, a foreign agent, searching the safe. But he overcame me and escaped."

"Oh--then that is what the--"

Elaine checked herself. She had been about to hand the note to Del Mar when an idea seemed to come to her. Instead, she crumpled it up and thrust it into her bosom.

On the street the bolero and the domino girl were hurrying away as fast as they could.

Meanwhile, the gray friar had overcome Del Mar, had bound and gagged him, and trust him into the closet. Then he wrote the note and laid it, with a rose from a vase, on Elaine's dressing-table before he, too, followed.

More than ever I was at a loss to make it out.

It was the day after the masquerade ball that a taxicab drove up to the Dodge house and a very trim but not over-dressed young lady was announced as "Miss Bertholdi."