The game is played with 72 stones. There are 36 different  stones,
each  occuring  twice. The stones are shuffled in a pouch. The player
takes an arbitrary  stone from the pouch and must put it on the board
somewhere. 

   The following rules must be followed:

   1. The stone must touch at least one other stone.

   2. If the stone touches only 1 other stone, the colours or symbols
      must be the same.

   3. If  the  stone  touches  2  other stones, it must have the same 
      colour as one of them, and the same symbol as the other.

   4. If  the  stone  touches  3  other stones, it must have the same
      colour  as one of them, and the same symbol as the other 2, and 
      vice versa.

   The object of the game is to place all 72 stones on the board.