Shirley endured a miserable three hours, in his attempts to locate the girl. She had not returned to the Hotel California, and he returned to the club in moody reflection. It was beginning to snow, and the ground was soon covered with a thin coat of white, through which he noticed his footprints stenciled against the black of the wet pavement. He wasted a dozen matches in the freshening wind, as he tried to light a cigarette. He stepped into a doorway on the Avenue to avail himself of its shelter. As he turned out to the street again, he almost bumped into two men, wearing black caps! One of them grunted a curt apology, as he stepped on.

“They are after me as usual,” he thought. “Why not reverse operations and find out where they belong?”

It seemed hopeless: as in a checker game they had him at disadvantage with the odd number of the “move.” Theirs was the chance to observe, and an open attempt to follow them would be ridiculous. Then, the footprints gave him an idea.

Dimly behind could be discerned the two men, as he quickened his pace, turning into a side street, off Fifth Avenue. Here he knew that traffic would be light, and his footprints the best evidence of his progress. The men unwittingly caught his plan, and dropped almost out of sight. At the intersection of Madison Avenue, they quickened their steps, and caught up with him again. Across corners, down quiet streets, and by purposed diagonals he led them: still they dogged his footprints. So adroit were they that only one experienced in the art could have realized their watchfulness.

Shirley now turned a corner quickly, into an unusually deserted thoroughfare, running with short steps, so as not to betray his speed by the tracks. Before they had time to round the corner he ran up the thinly blanketed steps of a private residence. Then he backed, as swiftly down the stoop, and thus crablike, walked across the street, down a dozen houses and backward still, up the steps of another private dwelling. Inside the vestibule he hid himself. The entry had strong wooden outside doors, and he tried the strength of the hinges: they satisfied him. A dim light burned behind the glass of the inner portal. He quietly clambered up the door, and balanced himself on the wood which gallantly stood the strain. Fortunately it did not come within four feet of the high ceiling of the old fashioned house.

He suffered a good ten minutes' wait before his ruse was rewarded. Being on the “fence” was a pastime compared to this precarious test of his muscles. The two men who had followed the first footprints tired of waiting before the house. One of them determined to investigate the other steps, which led into the house of their vigilance, from the other dwelling. And so he followed on, to the vestibule where he rang the bell. Shirley could have touched his head, so near he was, but the darkness of the upper space covered the retreat of the criminologist.

“What do you want?” was the angry question of an indignant old caretaker who answered the bell tardily. “You woke me up.”

“Say, lady, can I speak to Mr. Montague Shirley?” began the man, gingerly.

“You get away from this house, you loafer or I'll call the police. No one by that name ain't here. Now, you get!”

She slammed the door in his face.

“I'll get Chuck to watch de udder joint,” muttered the man, in a tone audible to Shirley. “Den I'll go back and git orders from Phil.”

This habit of thinking aloud was expensive. Shirley stiffly but noiselessly slid down the steps, as he disappeared in the thickening snowfall. The criminologist slowly crossed the street, and sheltered himself in a basement entrance, from which he reversed the shadowing process. The twain hesitated before the first house, then one came up the sidewalk, as the other stood his ground. This man passed within a few feet of Shirley, who followed him over to Madison Avenue, then north to Fifty-fifth Street. Here he turned west, and turned into one of the old stables, formerly used by the gentry of the exclusive section for their blooded steeds. Into one building, which announced its identity as “Garage” with its glittering electric sign, the man disappeared.

Shirley paused, looked about him, and chuckled. For he knew that through the block on Fifty-sixth Street was the tall apartment building, known as the Somerset—the address given him by Reginald Warren.

“If I only had some word from Helene Marigold I could go ahead before they realized my knowledge.”

Even as this thought crossed his mind, he turned back into Sixth Avenue. A hatless, breathless young person, running down the snowy street collided with him. As he began to apologize, he awoke to the startling fact that it was his assistant.

“Great Scott! What are you doing here? Where have you been all this time?”

The girl caught his arm unsteadily, but there was a triumph in her voice, as she cried: “Oh, this wonderful chance meeting. I was running down to my hotel but you have saved the day. I will tell you later. Quick, take this book.”

She drew forth a volume, flexibly bound, like a small loose-leaf ledger. Shirley stuck it into his overcoat pocket, which he was already slipping about the girl's shivering shoulders.

“Take me back at once, for there is more for me to do.”

“Where, my dear girl? You are indeed the lady of mysteries.”

“To the basement of Warren's apartment house. I came down the dumb-waiter, when they left me. I left the little door ajar—Can you pull me up again? He is on the eighth floor. It is a long pull—Oh, if we can only make it before they return.”

Her eyes sparkled with the thrill of the mad game, as she ran once more, Shirley keeping pace with her. The flurries of the snowstorm protected them from too-curious observation, as the streets seemed deserted by pedestrians who feared the growing blizzard. She led him to the tradesman's entrance of the Somerset, into the dark corridor through which she had emerged.

“Don't strike a light, for I can feel the way. We mustn't be seen.”

Shirley obeyed,—at last she found the base of the dumbwaiter shaft.

“How did you have the strength to lower yourself down this shaft—it is no small task?” and his tone was admiring.

“I am not a weakling—tennis, boating, swimming were all in my education; they helped. But it is beyond me to pull all those floors, and lift my weight. Pull up as far as the little elevator car goes, then go away and come to his party to look for me. Do not be surprised at my actions. My role has really developed into that of an emotional heavy.”

She patted his hand with a relaxation of tenderness, as he began to draw on the long rope. The girl was by no means a light weight, but at last the dumb-waiter came to a stop. Shirley heard the opening and closing of a door above. Then, still wondering at it all, he returned to the street as unobserved as they had entered. There was at least an hour to wait. He walked over to the Athletic Club, of which he was a remiss member, attending seldom during the recent months when his exercise had been more tragic than gymnastic work. In the library of the club house he sat down to study the volume which Helene had thrust into his hands at their startling meeting.

He gave a low whistle of surprise.

“Some little book!” he muttered, “and Helene Marigold has shown me that I must fight hard to equal her in the race for laurels!”

Then he proceeded to rack his brains with a new and knottier problem than any which he had yet encountered.