Text-book on Navigation and Nautical Astronomy |
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Common terms and phrases
Aldebaran altitude Approx artificial horizon August bearing by compass Bearing of distant blue pole centre chart chron chronometer circle coefficient comp compass bearing compass course correct magnetic bearing cosec course and distance declination deviation Diff distant object fast Find the lat Find the latitude Find true Fomalhaut G.M. noon given Greenwich heeling error height of eye horizontal hour angle inch knots latitude longitude magnetic courses magnetic equator mbars mean meridian Meridian Altitude miles Moon Moon's needle northern hemisphere observed P.M. at ship parallel parallel sailing Pegasi polar distance right angles Right Ascension sailing September set and drift sextant ship's head showed side Sidereal slow Spica standard compass star steering sub-permanent magnetism subtract Sun's Table tons true azimuth true dist variation vertex zenith
Popular passages
Page 373 - Square Measure 144 square inches (sq. in.) = 1 square foot (sq. ft.) 9 square feet = 1 square yard (sq. yd.) 30£ square yards = 1 square rod (sq. rd.) 160 square rods = 1 acre (A.) 640 acres = 1 square mile (sq.
Page 373 - Measure 12 inches (in.) = 1 foot (ft.) 3 feet = 1 yard (yd.) 5-j yards = 1 rod (rd.) 320 rods =1 mile (mi...
Page 299 - Northern hemisphere ; and what effect has it on the assumed position of the ship when she is steering on Northerly, and also on Southerly courses ? 17. The effect being as you state, on what courses would you keep away, and on what courses would you keep closer to the wind, in order to make good a given Compass course ? 18.
Page 308 - ... 16. State to which side of the ship, in the majority of cases, is the North point of the Compass drawn in the Northern hemisphere ; and what effect has it on the assumed position of the Ship when she is steering on Northerly, and also on Southerly courses ? 17.
Page 28 - The angle between the first and last directions of a ray which has suffered two reflections in one plane is equal to twice the inclination of the reflecting surfaces to each other. Let AB be the limb or graduated . arc, of a portion of a circle 60° in extent, but divided into 120 equal parts. On the radius CB let a silvered plane glass D be fixed, at right angles to the plane of the circle, and on the moveable radius CE let another such silvered glass, C, be fixed.
Page 44 - We have, then, that the sine of an angle is equal to the cosine of its complement, and conversely.
Page 373 - TABLE. 16 drams, (drs.) make 1 ounce, - marked - oz. 16 ounces ----- 1 pound, ----- lb. 28 pounds - - - , - - 1 quarter, ----- qr. 4 quarters ----- 1 hundred weight, - - cwt. 20 hundred weight - - 1 ton, ------ T.
Page 297 - Certificate is to answer correctly at least eight of such of the following questions as are marked with a cross by the Examiner. The Examiner will not mark less than 12 : — . I 1.
Page 308 - Determine the deviation, and name it east or west. 35. If an ordinary standard compass placed higher than the iron top sides be compensated whilst the ship is upright, what coefficient will be affected by heeling ? 36.
Page 307 - Compass to make the following courses, correct magnetic. 9. Supposing you have steered the following courses by the Standard Compass, find the correct magnetic courses made from the above deviation table.