"Motor Matt! Can I come in a minute?"
"Sure," replied Matt heartily.
A lithe, graceful form, in velvet and spangles, leaped lightly through the opening.
"Haidee!" exclaimed Matt, staring.
The girl bowed laughingly and threw a kiss, just as she was in the habit of doing after her trapeze work in the "big top."
"Yes, friends," she answered; "Haidee, the Flying Marvel, who is to do a turn on Motor Matt's flying machine just before the doors open. I am also to ride on the top wing of the Comet during the parade. Will I do?"
Lifting her arms, she pirouetted around for the observation of the boys, then paused and smiled bewitchingly.
"Do?" cried McGlory. "Why, sis, you'll be the hit of the piece. All I hope"—and McGlory's face went rather long—"is that you and Matt come through your trip in the air without any trouble."
"I'm not afraid!" declared Haidee.
"No more you're not, sis. If you were riding on the lower wing with Matt the whole game would be different; but you're to hang under the machine, and there'll be more pitching and plunging than if you were aboard a bucking bronk. Hang on, that's all, and don't try to hang by your heels."