From applicable 2 x 4 Columns.
First Two (#1 and #2) Circulate 4 spots & 1/4 In as 
  Last Two (#3 and #4) Circulate twice, 1/4 In, & Circulate.
Normal Columns end in Parallel Two-Faced Lines.
Notes:
- 
The First Two should make a wide arc for the 4 Column Circulates.  This movement
is sometimes described as Single File Promenade 1/2 Way & Veer Left|Right.
It starts and feels like the Beau's part of a Track 2.
- 
Only the First Two dancers can Roll.
- 
The First Two (#1 and #2) end as a Couple with each other; and 
    the Last Two (#3 and #4) end as a Couple with each other.  
    The lead dancer of each Tandem (#1 and #3) end as Ends, 
    and the trailing dancer of each Tandem (#2 and #4) end as Centers 
    in the resulting lines.  As such,
    it's important to establish your couple-relationship as soon as possible.  
    - For the First Two, Checkmate dances smoother as a Trail Off 
        to form a Couple; Couples Circulate; and Bend The Line.
- For the Last Two, Checkmate dances smoother as a Double Pass Thru; 
        Face In & join hands to form a Couple; and Couples Circulate.
 
Single Checkmate [C3A]:
 From a 2 x 2.  
  Leaders Box Circulate twice and 1/4 In 
  (Box Transfer) 
  as Trailers Box Circulate, 1/4 In, and Box Circulate.  
  Ends in a 2 x 2.
| |   |  |   |  | before Single Checkmate
 |  | after 
 | 
 | 
3 By 1 Checkmate [C2] (Willard Orlich):
 From Columns.  
  First Three dancers Column Circulate 4 positions & 1/4 In
  as the #4 dancers Circulate 3 positions, 1/4 In, & Circulate.  
  Ends in Parallel 3 & 1 Lines.
| |   |  |   |  | before 3 By 1 Checkmate
 |  | after 
 | 
 | 
Checkover [C1] (Al Appleton 1978):
 From Columns.  
  First Two Checkmate The Column as Last Two step foward to 
  form a Box (Circulate), Cast Off 3/4, Slither, and As Couples Extend.  
  Ends in Parallel Two-Faced Lines.