5. Closed Impetus and Feather Finish
The word impetus is defined as the force or energy that propels something. The Closed Impetus may have derived ts name from the impression one gets from watching a couple as they swing around each other, much as they do when dancing this figure. More specifically, during the Closed Impetus, the lady swings naturally around the man as he dances a heel turn.
The Impetus in Foxtrot begins in closed position with the man backing and lady facing line of dance. The man begins by stepping back on his left foot, closing his right foot to his left to dance a heel turn. The lady follows by stepping forward on her right foot, then sideways around the man. At this point they rise to toes, and the man then steps side & slightly back, lady diagonally forward. The slight difference in their direction of travel on this last step owes to the fact that the man is stepping slightly around the lady, as the rotation continues until the last step has begun to receive weight. In total, they will have turned 5/8 to right.
In the Foxtrot syllabus, the Impetus is always followed by a Feather Finish. This is the same Feather Finish as described in the Reverse Turn, with the one exception that in most cases it is danced with only 1/4 turn to left overall (bodies slightly less to accommodate the outside partner position on the final step). This leaves the dancers moving toward diagonal center to dance a reverse action, or at a corner, moving toward diagonal wall of the new line of dance to follow with a Three Step.
As a variation, one could indeed choose to take the full 3/8 turn of the normal Feather Finish following an Impetus if danced at a corner. This could then be followed either by a Three Step moving down line of dance, or by a Reverse Turn, Check and Basic Weave.