## The New American Practical Navigator: Being an Epitome of Navigation : Containing All the Tables Necessary to be Used with the Nautical Almanac, in Determining the Latitutde, and the Longitude by Lunar Observations : and Keeping a Complete Reckoning at Sea : the Whole Exemplified in a Journal, Kept from Boston to Madeira : with an Appendix Containg Methods of Calculating Ex\clipses of the Sun and Moon, and Occultations of the Fixed StarsE. M. blunt, 1826 - 617 pages |

### From inside the book

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**is to their difference , as the tangent of half the sum of**the angles at the base is to the tangent of half the difference of the same angles . Thus , in the triangle ABC , if we call AB the base , it will be as the sum of AC and CB is ...### Other editions - View all

### Common terms and phrases

anchor angle arch azimuth bearing cable calculated Cape centre co-sec column compass correction corresponding course and distance course sailed degrees Diff difference of latitude difference of longitude Dist draw elapsed equal equator error EXAMPLE feet find the course Funchal given Greenwich half sum haul helm horizon glass hour angle hypotenuse latitude and departure Latitude Sailing line of numbers line of sines logarithm lower limb mast mean meridian altitude method middle latitude miles minutes mizen moon moon's multiplied Nautical Almanac nearly noon object observed altitude parallax parallel Parallel Sailing passing the meridian perpendicular Plane Sailing points radius 90 refraction right ascension rope rule sea account secant semi-diameter sextant ship ship's side Sine Course star staysail subtracted sun's declination Suppose taken tangent telescope tion TRAVERSE TABLE triangle true distance tude variation wind zenith distance

### Popular passages

Page 7 - In any plane triangle, the sum of any two sides is to their difference as the tangent of half the sum of the opposite angles is to the tangent of half their difference. By Theorem II. we have a : b : : sin. A : sin. B.

Page 22 - To find the logarithm of a vulgar fraction. RULE. Subtract the logarithm of the denominator from the logarithm of the numerator...

Page 177 - If the vessel be double-decked, take the length thereof from the fore part of the main stem, to the after part of the stern post, above the upper deck"; the breadth thereof at the broadest part above the main wales...

Page xii - The circumference of a circle is supposed to be divided into 360 equal parts called degrees, and each degree into 60 equal parts called minutes, and each minute into 60 equal parts called seconds, &c.

Page 197 - The cause of the tides is the unequal attraction of the sun and moon upon different parts of the earth. For they attract the parts of the earth's surface nearest to them, with a greater force than they do its centre : and attract the centre more than they do the opposite surface. To restore this equilibrium the waters take a spheroidal figure, whose longer axis is directed towards the attracting luminary.

Page 23 - DIVISION BY LOGARITHMS. RULE. From the logarithm of the dividend subtract the logarithm of the divisor ; the remainder will be the logarithm of the quotient EXAMPLE I.

Page xii - A plane rectilineal angle is the inclination of two straight lines to one another, which meet together, but are not in the same straight line.

Page 229 - Broadside; a discharge of all the guns on one side of a ship, both above and below.

Page 196 - ... near the longitude of Sumatra and Java. In the tract between Sumatra and the African coast, and from 3° of south latitude, quite northward to the Asiatic coast, including the Arabian Sea and the Bay of Bengal, the monsoons blow from October to April on the NE and from April to October on the SW In the former half year, the wind is more steady and gentle, and the weather clearer than in the latter six months. In the Red Sea the winds blow nearly nine months of the year from the southward, that...