When a short time had passed, the dark shape slipped through the doorway and went pattering quietly down the stairs.

Dark, low shapes dash out of the trees and slip among the horses' ankles.

The female shape slipped into one, he into the other.

A thin, tall shape slipped into the chair opposite.

A minute later a black shape emerged and slipped noiselessly through the air above them.

Burke's black-clad shape rose from the shadows and slipped behind the second man.

The door opened slowly and a dark shape slipped in.

Well behind them, another shape, even dimmer, slipped between the trees.

When the area of grayness was wide enough, a black shape slipped through it.

Barely visible through the haze, three giant shapes slipped past the mouth of the bay.