This may not be a complete list of all calls authored by Van Vanderwalker.
Half Breed Thru - A1
Jay King - page 39
From facing lines of four with one couple regular and the other half sashayed: Pass thru. If you have a girl on your right, courtesy turn to face in. If the girl is on your left, both of you individually U-turn back to finish in regular facing lines.
Van Vanderwalker 1955
This definition is from The Handbook of Modern Square Dancing by Jay King.
It is provided here for informational and educational purposes only.