A guide book to the Local marine board examination. The ordinary examination. [With] The requisite elements from the Nautical almanac for 1865, for the exercises in Ainsley's Guide book, Volumen24 |
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Página 162
... central line is then intersected at each of the 32 points by two straight lines , one a plain line and the other a dotted line . The plain and dotted lines make an angle of 60 ° with the central line and with each other , and so forming ...
... central line is then intersected at each of the 32 points by two straight lines , one a plain line and the other a dotted line . The plain and dotted lines make an angle of 60 ° with the central line and with each other , and so forming ...
Página 163
... central line , westerly deviations to the left . * The amount of the deviation is taken from the scale of degrees on the central line ; then , if the deviation has been determined with the ship's head on an exact compass point , lay off ...
... central line , westerly deviations to the left . * The amount of the deviation is taken from the scale of degrees on the central line ; then , if the deviation has been determined with the ship's head on an exact compass point , lay off ...
Página 164
... central line a distance equal to deviation 13 ° , and from N.E. on the central line lay it off on the dotted to the left- deviation being W .; and the point so determined ... central line a distance equal to 164 Deviation of the Compass .
... central line a distance equal to deviation 13 ° , and from N.E. on the central line lay it off on the dotted to the left- deviation being W .; and the point so determined ... central line a distance equal to 164 Deviation of the Compass .
Página 165
Thomas Liddell Ainsley. 3. Take from the central line a distance equal to 261 ° ( 26 ° 50 ′ ) , and lay it off on the dotted line , from East towards the right — being E .; make a dot or cross . 4. Take from the central line a distance ...
Thomas Liddell Ainsley. 3. Take from the central line a distance equal to 261 ° ( 26 ° 50 ′ ) , and lay it off on the dotted line , from East towards the right — being E .; make a dot or cross . 4. Take from the central line a distance ...
Página 166
... central line find the given course ; then , with a pair of dividers , measure the distance from that point to where the curve cuts the dotted line passing through the course ; but if no dotted line proceeds from the course , then ...
... central line find the given course ; then , with a pair of dividers , measure the distance from that point to where the curve cuts the dotted line passing through the course ; but if no dotted line proceeds from the course , then ...
Términos y frases comunes
A.M. at ship altitude sun's L.L. angle bearing by compass Bearing of Distant Brest central line chart chronometer showed column common logarithms compass course correct magnetic bearing correct magnetic course corresponding cosec cosine course and distance curve cyphers decl declination departure Deviation Required diff difference of latitude difference of longitude Distant Object Divide divisor East error of compass EXAMPLES FOR PRACTICE figure given gives hour-angle Greenwich date Greenwich mean Head by Standard height of eye high water hour-angle 3h hundred index corr index correction mantissa mean noon miles Multiply Nautical Almanac needle noon at Greenwich NORIE North Object by Standard observed altitude sun's observed meridian altitude parallel parallel sailing quotient Raper remainder required the latitude Rule sailing semid sextant ship's head sine South Standard Compass steered subtracted Table tide true alt True altitude true azimuth true course West
Pasajes populares
Página 59 - The Logarithm of a number to a given base is the index of the power to which the base must be raised to give the number. Thus if m = a", x is called the logarithm of m to the base a.
Página 2 - He must understand the use of the sextant, and be able to observe with it, and read off the arc. In SEAMANSHIP. — He must give satisfactory answers as to the rigging and unrigging of ships, stowing of holds, &c. ; must understand the measurement of the log-line, glass, and lead-line ; be conversant with the rule of the road, as regards both steamers and sailing vessels, and the lights carried by them.
Página 39 - PROOF. — Multiply the divisor by the quotient, and to the product add the remainder, if any.
Página 146 - ... upon so long as she remains upright. Besides the ordinary deviation of the compass there is a deviation caused by the heeling of iron ships, which may increase or decrease the deviation observed when the ship is upright. Cases have been observed in which the deviation from heeling has amounted to as much as two degrees for each degree of heel of the ship, that is, without altering the real direction of the ship's head, the apparent alteration in direction has amounted to 40° by heeling the ship...
Página 229 - AVhen this time is exactly one of the instants for which the required quantity is put down in the Ephemeris, nothing more is necessary than to transcribe the quantity as there put down. But when, as is mostly the case, the time falls between two of the times in the Ephemeris, we must obtain the required quantity by interpolation. To facilitate this interpolation, the Ephemeris contains the rate of change, or difference of each of the quantities in some unit of time.
Página 378 - 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.
Página 103 - The COURSE steered is the angle between the meridian and the ship's head. The course made good is the angle between the meridian and the ship's real track on the surface of the sphere. The course is reckoned from the north, towards the east or west, when the ship's Ivead is less than eight points from the north point. The same applies to the south point. The course is measured in points of 11° 15' each, or in degrees and minutes.
Página 2 - Testimonials of character, and of sobriety, experience, ability, and good conduct on board ship, will be required of all applicants, and without producing them no person will be examined. As such testimonials...
Página 386 - To be added when the greater reading is off the arc, and subtracted when the greater reading is on the arc. 14.
Página 378 - With the deviation as above, give the courses you would steer by the Standard Compass to make the following courses, correct magnetic : — . . 9.