He heard a tap at the door, and a figure slipped into the darkness.
A few figures slip between both camps, as the mood takes them.
A tall figure slipped inside the hall and walked toward the single forge in use.
That figure slipped to 10.3 percent in March, still a high level.
By 1990, the figure had slipped to 85 percent.
Last year, the figure had slipped to 28 percent.
A dark figure slipped from behind the scaffolding and ran across the floor.
By 1988 the figure had slipped to 47.1 percent.
But going into the Christmas holiday, that figure slipped behind last year's.
An instant later the figure had slipped away into the darkness!