Navigation and Seamanship

4.3.6. Lighthouse and lightships

Lighted navigational aids are essentially required to assist navigator in conducting the vessels during night hours. Therefore, the navigator must have knowledge of the light characteristics of the aids to navigation. Light house is one of the important lighted navigational aid, are placed in a height with powerful light to assist the navigator or wherever a danger requires a warning. Light houses are placed where they will be of most use, on prominent headlands, at entrances, on isolated dangers, or at other points where it is necessary that mariners by warned or guided. Their principal purpose is to support a light at a considerable height above the water. Visibility of a light increases with height of the beacon above the sea level. A lighthouse can also be used for keeping fog-signaling and radio beacon equipment. In earlier days lights were operated by keepers are now fully automatic with timers .

Solid colors, bands, stripes, and other color patterns are applied to lighthouses and light structures as an aid to identification. Minor structures sometimes are painted red or black, like channel buoys, to indicate the side of the channel on which they are located--red structures to the right, black to the left, returning seaward. The location of a light house whether in the water or on shore, the importance of the light, and the kind of soil upon which it is to be built and the prevalence of violent storms, have a direct bearing upon the type of structure erected and on the materials. Outward appearance of light house is important, because of the great difference in the distances from which their lights should be seen.