private boolean testVertical(String[][] allMarkers) {
        for (int i = 5; i >= 3; i--) {
            for (int j = 0; j <= 6; j++) {
                if ("_".equals(allMarkers[i][j])) {}
                else  {
                    if (allMarkers[i][j].equals(allMarkers[i-1][j]) && 
                        allMarkers[i][j].equals(allMarkers[i-2][j]) &&
                        allMarkers[i][j].equals(allMarkers[i-3][j]))
                        return true;        
                }  
            }
        }
        return false;
    }