As Eileen Erroll emerged from the surf and came wading shoreward through the seething shallows, she caught sight of Selwyn sauntering across the sands toward the water, and halted, knee-deep, smilingly expectant, certain that he had seen her.

Gladys Orchil, passing her, saw Selwyn at the same moment, and her clear, ringing salute and slender arm aloft, arrested his attention; and the next moment they were off together, swimming toward the sponson canoe which Gerald had just launched with the assistance of Sandon Craig and Scott Innis.

For a moment Eileen stood there, motionless.  Knee-high the flat ebb boiled and hissed, dragging at her stockinged feet as though to draw her seaward with the others.  Yesterday she would have gone, without a thought, to join the others; but yesterday is yesterday.  It seemed to her, as she stood there, that something disquieting had suddenly come into the world; something unpleasant—­but indefinite—­yet sufficient to leave her vaguely apprehensive.

The saner emotions which have their birth in reason she was not ignorant of; emotion arising from nothing at all disconcerted her—­nor could she comprehend the slight quickening of her heart-beats as she waded to the beach, while every receding film of water tugged at her limbs as though to draw her backward in the wake of her unquiet thoughts.

Somebody threw a tennis-ball at her; she caught it and hurled it in return; and for a few minutes the white, felt-covered balls flew back and forth from scores of graceful, eager hands.  A moment or two passed when no balls came her way; she turned and walked to the foot of a dune and seated herself cross-legged on the hot sand.

Sometimes she watched the ball players, sometimes she exchanged a word of amiable commonplace with people who passed or halted to greet her.  But she invited nobody to remain, and nobody ventured to, not even several very young and ardent gentlemen who had acquired only the rudiments of social sense.  For there was a sweet but distant look in her dark-blue eyes and a certain reserved preoccupation in her acknowledgment of salutations.  And these kept the would-be adorer moving—­wistful, lagging, but still moving along the edge of that invisible barrier set between her and the world with her absent-minded greeting, and her serious, beautiful eyes fixed so steadily on a distant white spot—­the sponson canoe where Gladys and Selwyn sat, their paddle blades flashing in the sun.

How far away they were. . . .  Gerald was with them. . . .  Curious that Selwyn had not seen her waiting for him, knee-deep in the surf—­curious that he had seen Gladys instead. . . .  True, Gladys had called to him and signalled him, white arm upflung. . . .  Gladys was very pretty—­with her heavy, dark hair and melting, Spanish eyes, and her softly rounded, olive-skinned figure. . . .  Gladys had called to him, and she had not. . . .  That was true; and lately—­for the last few days—­or perhaps more—­she herself had been a trifle less impulsive in her greeting of Selwyn—­a little less sans-facon with him. . . .  After all, a man comes when it pleases him.  Why should a girl call him?—­unless she—­unless—­unless—­