The Great Lakes Area. cee sce ke 3 St. Lawrence—Great Lakes Waterway. . z ; Meaning of Boat Whistles . Nautical Measurements. .... eli How Navigational Locks Operate 12 Channel Buoy Guide 13 Talking Lights 14 Nautical Terms. 15 17 18 18 19 The St. Lawrence Seaway... Plimsoll Markings gers sels. United States and Canadian Stack Marange: Flags of all Nations -60 Stack Markings of Major World Shipping Companies... 62 Overseas Vessels and Trips into the Great Lakes, 1993. 108 SHIPSMUSOUMNS secre eens ee eines mers ie thet sine 120 jackson moves towards the Soo northwest pier. (R.