Titlebook: Marine Navigation 1 : Piloting; Richard R. Hobbs Book 1981 United States Naval Institute 1981 Marine.bridge.distance.information.instrumen

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The Nautical Chart,nctional responsibilities. Maps, charts, and written sailing directions were probably in use by Egyptian and Greek mariners in the Mediterranean Sea well before the birth of Christ. Ptolemy, a Greek astronomer and mathematician, constructed many maps in the second century A.D., among which was a wor

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Canvas

Visual Navigation Aids,en established that a lighthouse was built at Sigeum, near Troy, in the seventh century B.C., and in Alexandria in Egypt in the third century B.C. Wood fires furnished their illumination; wood and sometimes coal continued to be used for this purpose until the invention of the electric light in the n

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Navigational Instruments, This chapter will describe many of the more common instruments used by U.S. Navy, American Merchant Marine, and private navigators. Although navigational instruments may be classified in a number of ways, they will be considered here in groups according to the following purposes: instruments to mea

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Dead Reckoning,present position of his ship, but equally as important, the navigator must also be able to calculate the ship’s probable position at future times. To put it in simple terms, the navigator continually seeks answers to the following questions: “Where is the ship now?” and, “Where is the ship going to

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Shipboard Compasses,graphic meridian. The horizontal direction of one terrestrial point from another, expressed as an angle from 000° clockwise to 360°, is termed a .. Bearings measured using the ships longitudinal axis as the reference direction are called ., indicated by the abbreviation R following the bearing. Thos

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高调

Tide,d to a lesser extent of the sun, upon different parts of the earth is called .. This phenomenon is of great interest and importance to the navigator, especially when he is piloting in relatively shallow coastal waters, because the height of tide determines the total depth of water at any given locat

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