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4.3.1.1 Importance of aids to navigation
These aids are of tremendous assistance to the navigator in making a landfall when approaching from seaward, and in all coastal navigation. Their importance was first recognized by the ancient Mediterranean mariners; a lighthouse was built at Sigeum, near Troy, before 600 B.C., and the famous Pharos of Alexandria was built in the third century B.C. Wood fires furnished their illumination, and wood and sometimes coal remained in general use for this purpose until the eighteenth century. The first lighthouse in the United States was built at Boston in 1716, and logs and kegs were used as buoys in the Delaware River in 1767. Aids to navigation take a wide variety of forms; some are very simple unmanned objects, others are complex and costly devices, sometimes with operating crews in attendance. All serve the same goal- the safety of vessels and those on board; difference in type, size, etc., are determined by the circumstances of location and use. |