“Not as bad as that, I guess,” said Carter. “I think Mrs. Thurlow would have told me. Step down that way and keep an eye on her. We now must watch her constantly.”
Both had been standing in an alcove formed by the rise of the broad, main stairway. The latter led up to a wide corridor flanking three sides of the ballroom, which was accessible from each through several broad, pillared doorways. In the end wall of the room was a row of open French windows, leading out upon the balcony roof of a wide veranda overlooking an avenue through the park mentioned, in which numerous automobiles already had gathered to await the end of the festivities.
One among them had arrived quite early and obtained a position of special advantage, close to the broad avenue and within easy view of the veranda and balcony. It attracted no more attention than any of the others, neither did the chauffeur, who sat motionless at his wheel. None would have recognized his bearded face, nor could the car have been traced from the license number it then appeared to bear.
It was to these conditions and surroundings that Professor Karl Graff had referred while talking with Dorson in the road house, and of which he and his knavish confederates were prepared to take every advantage.
Chick slipped away from his chief, as the latter had directed, and took a position from which he could watch the door of a room to which Mrs. Thurlow and Edna had gone to leave their outside garments, while Dorson hastened to another to check his crush hat and Inverness. Though his face was unusually pale and grave, it wore no expression inviting suspicion.
He returned in a few moments and rejoined Edna Thurlow, departing with her through the throng in the lower corridor and mingling with the stream of wealth and fashion then seeking the ballroom.
Mrs. Thurlow came out a little later and joined a group of women acting as a reception committee, and for nearly an hour she remained in the lower hall, apparently undisturbed by the threats of which she had been informed, and conducting herself precisely as if ignorant of them, as Carter had directed.
Both detectives, though they then were separated, had an eye on her all the while and on the rope of lustrous pearls adorning her shapely neck and perfect shoulders. Neither could detect any person near her inviting suspicion, however, and it really seemed improbable that so daring a theft could be successfully committed, in view of the fact that it had been predicted and prevention audaciously invited.
It was ten o’clock when Mrs. Thurlow went up to the lavishly decorated ballroom. There, and in the adjoining corridors, a throng of several hundred guests were assembled. A dance then was in progress, however, and the corridors were less crowded than during the intervals between the dances.
Carter and Chick met on the stairs while following the woman quite closely, and Carter said a bit hurriedly, noting the direction she was taking: