The first half-dozen couples Lane studied all danced more or less as Helen and Swann had, that day in Helen’s studio.  Then, by way of a remarkable contrast, there passed two young people who danced decently.  Lane descried his sister Lorna in the throng, and when she and her partner came round in the giddy circle, Lane saw that she wiggled and toddled like the others.  Lane, as she passed him, caught a glance of her eyes, flashing, reproachful, furious, directed at some one across her partner’s shoulder.  Lane followed that glance and saw Swann.  Apparently he did not notice Lorna, and was absorbed in the dance with his own partner, Helen Wrapp.  This byplay further excited Lane’s curiosity.  On the whole, it was an ungraceful, violent mob, almost totally lacking in restraint, whirling, kicking, swaying, clasping, instinctively physical, crude, vulgar and wild.  Down the line of chairs from his position, Lane saw the chaperones of the Prom, no doubt mothers of some of these girls.  Lane wondered at them with sincere and persistent amaze.  If they were respectable, and had even a slight degree of intelligence, how could they look on at this dance with complacence?  Perhaps after all the young people were not wholly to blame for an abnormal expression of instinctive action.

That dance had its several encores and finally ended.

Margaret and Holt made their way up to Lane and Blair.  The girl was now radiant.  It took no second glance for Lane to see how matters stood with her at that moment.

“Say, beat it, you two,” suddenly spoke up Blair.  “There comes Swann.  He’s looking for you.  Chase yourselves, now, Marg—­Holt.  Leave that slacker to us!”

Margaret gave a start, a gasp.  She looked hard at her brother.  Blair wore a cool smile, underneath which there was sterner hidden meaning.  Then Margaret looked at Lane with slow, deep blush, making her really beautiful.

“Margie, we’re for you two, strong,” said Lane, with a smile.  “Go hide from Swann.”

“But I—­I came with him,” she faltered.

“Then let him find you—­in other words, let him get you....  ’All’s fair in love and war.’”

Lane had his reward in the sweet amaze and confusion of her face, as she turned away.  Holt rushed her off amid the straggling couples.

“Dare, you’re a wiz,” declared Blair.  “Margie’s strong for Holt—­I’m glad.  If we could only put Swann out of the running.”

“It’s a cinch,” returned Lane, with sudden heat.

“Pard, you don’t know my mother.  If she has picked out Swann for Margie—­all I’ve got to say is—­good night!”

“Even if we prove Swann——­”

“No matter what we prove,” interrupted Blair.  “No matter what, so long as he’s out of jail.  My mother is money mad.  She’d sell Margie to the devil himself for gold, position—­the means to queen it over these other mothers of girls.”

“Blair, you’re—­you’re a little off your nut, aren’t you?”