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12. LOADLINE MARKS
These curious marks on the side of the ship (usually just above the waterline, are official marks showing the maximum depth the vessel may be loaded down to, (If the ship is loaded down further, it may sink !). It used to be called the "plimsole line", but now is governed by the International Load Line Convention. There are 3 lines, one for tropical waters, one for summer time and one for winter time.