As rank has its privilege ... the player with the Officer stones starts the game by placing a yellow stone in any position on a radial. The opponent may then place a Sailor blue stone in any other position on any radial ... and so on. Position stones on the radial lines of degrees where they intersect the concentric circles in the compass.

Place the stones, one at a time, building on those already on the board to complete &/or block new point-winning rhumb lines.
As the game progresses, several point combinations may be completed with a single turn.
e.g. a stone placed on NW completes a Radius = 10 points
and a Spiral = 30 points
for a total of 40 points.
Radius & Arc & Spiral = 60 Points ...
2 Spirals = 60 Points ... Arc & Spiral = 50 Points ...
2 Arcs = 40 Points ... Radius & Arc = 30 Points.

Players keep score on their end of the board with the extra stone of their color. After 100 points ... adding to and continuing from 10. Points overlooked and not marked before the opponent takes a turn are forfeited. Once the stone being played is released, it may not be moved ... with the following exception.

When just 1 stone each remains, players remove 1 of their stones from the board (once only) and on their next turn, place it in any position ... other than the one from which it was removed. The game is over when all 32 positions on the compass rose are covered and the higher scoring player is the winner of ... Rhumb Line.