Your quick-reference, on-board guide to the symbology and shorthand notations used on nautical charts Nautical charts contain an incredible amount of information for those who know how to decipher them. But without a key to the symbology, a chart can be bewildering. Nigel Calder, one of today's most respected boating authors, helps you make sense complex system of signs, symbols, and graphic elements with this compact, waterproof, and nearly indestructible guide.