From two parallel waves: Ends arm turn adjacent dancer 3/4, new centers Trade then arm turn new ends 3/4. Finishes in two parallel waves.
COMMENT: This move is part of an older call "Swing The Square" by Ed Hall, Meadville, PA. In Swing the Square, from parallel waves, Ends arm turn 3/4, new centers arm turn half, ends arm turn 3/4, new centers arm turn half, etc. until all dancers have returned to original positions in original waves.
NOTE: The first two moves of this go under the name of Three Quarter Thru which is a term on the Challenge Dancing's Basic Calls list.
After Chain The Line, several other names were given to this same or closely similar moves as follows:
See Cast Chain Thru, Grand Chain Thru, Spinning Wheel, Split The Difference.
This definition is from The Handbook of Modern Square Dancing by Jay King.
It is provided here for informational and educational purposes only.