It was a huge, bare hall, although the walls were concealed by flags, while other draperies were festooned along the rafters.  The band was stationed upon a raised platform at the rear, and a hundred couples occupied the floor.  The men present were largely officers attired in dress-uniforms, although there was a considerable sprinkling of civilians, a few conspicuous in garments of the latest cut and style.  Evidently invitations had been widely spread, and, considering time and place, liberally responded to.  Among the women present the Sergeant saw very few he recognized, yet it was comparatively easy to classify the majority—­officers’ wives; the frontier helpmates of the more prominent merchants of the town; women from the surrounding ranches, who had deserted their homes until the Indian scare ceased; a scattered few from pretentious small cities to the eastward, and, here and there, younger faces, representing ranchmen’s daughters, with a school-teacher or two.  Altogether they made rather a brave show, occasionally exhibiting toilets worthy of admiring glances, never lacking ardent partners, and entering with unalloyed enthusiasm into the evening’s pleasure.  The big room presented a scene of brilliant color, of ceaselessly moving figures; the air was resonant with laughter and trembling to the dashing strains of the band.  Primitive as it was in many respects, to Hamlin, long isolated in small frontier posts, the scene was strangely attractive, his imagination responding to the glow of color, the merry chime of voices, the tripping of feet.  The smiling faces flashed past, his ears caught whispered words, his eyes followed the flying figures.  For the moment the man forgot himself in this new environment of thoughtless pleasure.

From among that merry throng of strangers, his eyes soon distinguished that one in whom he felt special interest—­Mrs. Dupont, dancing now with McDonald, the rather corpulent Major exhibiting almost youthful agility under the inspiration of music.  The lady talked with animation, as they circled among the others on the floor, her red lips close to her partner’s ear, but Hamlin, suspicious and watchful, noted that her eyes were busy elsewhere, scanning the faces.  They swept over him apparently unseeing, but as the two circled swiftly by, the hand resting lightly on the Major’s shoulder was uplifted suddenly in a peculiar, suggestive movement.  He stared after them until they were lost in the crowd, feeling confident that the motion of those white-gloved fingers was meant as a signal of warning.  To whom was it conveyed?  He glanced aside at the jam of figures in the doorway.  Both the black-whiskered man and Connors had disappeared.  It was a signal then, instantly understood and obeyed.