Definition of "vanishing"

Selwyn, sitting up rumpled and cross-legged on the floor, after having boloed Drina to everybody's exquisite satisfaction, looked around at the sudden rustle of skirts to catch a glimpse of a vanishing figure—a glimmer of ruddy hair and the white curve of a youthful face, half-buried in a muff.

1907 August, Robert W[illiam] Chambers, chapter I, in The Younger Set, New York, N.Y.: D. Appleton & Company