Ada and her chums did not come down to dinner that night, and so did not help with the decorating of the hall.  That was pronounced an unqualified success, as was the performance of “The Violet Patchwork” the following night and the nut cake and the chocolate and the pistache ice-cream that was served at the close.

Both audience and players were treated to two surprises in the course of the evening.  Bobby was responsible for one and, much to the astonishment of the school, Ada Nansen and Constance Howard for the other.

True to her promise, the dauntless Bobby had accepted the humble role of stage hand rather than have no part in the play, and she trundled scenery with right good will and acted as Miss Anderson’s right hand in a mood of unfailing good humor.  There was not an atom of envy in Bobby’s character, and she thought Betty the most wonderful actress she had ever seen.

“You look lovely in that dress,” she said, as Betty stood awaiting her cue at the opening of the second act.

Betty smiled, took her cue and walked on the stage.

A ripple of laughter that grew to hilarity greeted her after the first puzzled moment.

“Oh, oh!” cried Madame hysterically, in the wings.  “See, that Bobby!  Some one call her!  She is walking with the tree!”

The rather primitive arrangements of the background provided for the play called for a girl to stand behind each tree in the formal garden scene as support.  In her admiration of Betty, Bobby had unconsciously edged after her to keep her in sight, and the startled audience saw the heroine being persistently pursued by a pretty boxwood tree.  Bobby was recalled to herself, the tree became rooted in its place, and “The Violet Patchwork” proceeded smoothly.

Between the third and fourth acts, the lights went out at a signal and to the general surprise—­for the players had known nothing of what was to come—­a velvety voice rolled out in the darkness singing the words of “A Maid in a Garden Green,” a song a great singer had made popular that season.

“It’s Ada,” whispered the school with a rustle of delight.  “No one else can sing like that.”

They encored her heartily, and she responded.  Then the lights flared up and died down again for the last act.

“Constance got her to do it,” whispered Betty to Bobby.  “I heard Miss Anderson telling Miss Sharpe.  Ada’s face is so scratched she couldn’t, or rather wouldn’t, show herself, and Constance said why not sing in the dark the way they do at the movies?  That tickled Ada—­who’d like to be a movie actress, Connie says—­and she said she would.”

“Constance Howard has a way with her,” remarked Bobby sagely.  “Any one that can persuade Ada Nansen to do anything nice is qualified to take a diplomatic post in Thibet.”

Soon after the play the weather turned colder and skating and coasting became popular topics of conversation.  There was not much ice-skating, as a rule, in that section of the country, but snow was to be expected, and more than one girl had secret aspirations to go from the top of the hill back of the school as far as good fortune would take her.