The Practice of Navigation: And Nautical AstronomyJ. D. Potter, 1882 - 910 σελίδες |
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Αποτελέσματα 1 - 5 από τα 90.
Σελίδα 117
... corr . for index error , -3 ' ; the height of the eye , 20 feet ; estimated Dist . 8 leagues , or 24 miles : required its Distance . Deducting of 24 , or 2 ′ , and 3 ′ error , leaves true alt . 51 ′ . True alt . 51 ' True Depr . to 20 ...
... corr . for index error , -3 ' ; the height of the eye , 20 feet ; estimated Dist . 8 leagues , or 24 miles : required its Distance . Deducting of 24 , or 2 ′ , and 3 ′ error , leaves true alt . 51 ′ . True alt . 51 ' True Depr . to 20 ...
Σελίδα 129
... corr . required . Apply the corr . to the N. in N. Lat , and to the S. in S. Lat . Ex . The observer in N. lat . 40 ° 2 ' sees a peak in lat . 40 ° 9 ′ N. , and 1 ° 54 ′ W. of him : required the true azimuth , as deduced from the rhumb ...
... corr . required . Apply the corr . to the N. in N. Lat , and to the S. in S. Lat . Ex . The observer in N. lat . 40 ° 2 ' sees a peak in lat . 40 ° 9 ′ N. , and 1 ° 54 ′ W. of him : required the true azimuth , as deduced from the rhumb ...
Σελίδα 147
... Corr . of Alt . is given in Table 39 ; that of a star is merely its refraction . 439. The SEMI - DIAMETER of a celestial body is half the angle subtended by the diameter of the visible disc . Thus to a spectator at S the semi - diameter ...
... Corr . of Alt . is given in Table 39 ; that of a star is merely its refraction . 439. The SEMI - DIAMETER of a celestial body is half the angle subtended by the diameter of the visible disc . Thus to a spectator at S the semi - diameter ...
Σελίδα 164
... CORR . subtract I 10 Ex . 2. On the arc Off IND . CORR . add 30 ′ 10 ′′ 33 40 3 30 I 45 In consequence of the spring or elasticity of the index - bar , the error will be different for the onward and for the backward motion of the index ...
... CORR . subtract I 10 Ex . 2. On the arc Off IND . CORR . add 30 ′ 10 ′′ 33 40 3 30 I 45 In consequence of the spring or elasticity of the index - bar , the error will be different for the onward and for the backward motion of the index ...
Σελίδα 165
... corr . , and applying the other star's correction the opposite way to that laid down in the tabulated directions for the star . § A second fixed horizon - glass is usually attached to quadrants , for the purpose of refer . ring the ...
... corr . , and applying the other star's correction the opposite way to that laid down in the tabulated directions for the star . § A second fixed horizon - glass is usually attached to quadrants , for the purpose of refer . ring the ...
Άλλες εκδόσεις - Προβολή όλων
The Practice of Navigation and Nautical Astronomy Henry Raper Δεν υπάρχει διαθέσιμη προεπισκόπηση - 2018 |
The Practice of Navigation and Nautical Astronomy (Classic Reprint) Henry Raper Δεν υπάρχει διαθέσιμη προεπισκόπηση - 2017 |
The Practice of Navigation and Nautical Astronomy Henry Raper Δεν υπάρχει διαθέσιμη προεπισκόπηση - 2018 |
Συχνά εμφανιζόμενοι όροι και φράσεις
add the log altitude alts appears azim azimuth bearing celestial body centre chron chronometer circle compass Computation corr correction cosec D.Lat Dist decimal decl declination deviation diff difference direction divided employed equal equator error exceeds extr feet given gives greater Greenwich Date height of eye Hence horizon hour-angle interval latitude less logarithms longitude lunar magnetic mean measured meridian method miles moon moon's Nautical Almanac nearly noon observation parallax parallel Parallel Sailing Plane Sailing pole port prime vertical prop quantity reckoned reduce refraction result rhumb line Right Ascension sailing Semid sextant shews ship ship's side sine star subtract sum rejecting tens sun's TRAVERSE TABLE triangle true true alt variation watch
Δημοφιλή αποσπάσματα
Σελίδα 41 - The angle in a semicircle is a right angle ; the angle in a segment greater than a semicircle is less than a right angle; and the angle in a segment less than a semicircle is greater than a right angle.
Σελίδα 19 - The characteristic of a number less than 1 is found by subtracting from 9 the number of ciphers between the decimal point and the first significant digit, and writing — 10 after the result.
Σελίδα 38 - A parallelogram is a four.sided figure, of which the opposite sides are parallel; and the diameter is the straight line joining two of its opposite angles.
Σελίδα vii - This is the more important, as very indistinct and erroneous notions prevail among practical persons on the subject of accuracy of computation ; and much time is, in consequence, often lost in computing to a degree of precision wholly inconsistent with that of the elements themselves. The mere habit of working invariably to a useless precision, while it can never advance the computer's knowledge of the subject, has the unfavourable tendency of deceiving those who are not aware of the true nature...
Σελίδα 147 - For the same body the semidiameter varies with the distance; thus, the difference of the sun's semidiameter at different times of the year is due to the change of the earth's distance from the sun; and similarly for the moon and the planets.
Σελίδα 22 - A CIRCLE is a figure bounded by a curve line called the circumference,* of which every point is at the same distance from a point within, called the centre. Thus, ABD is a circle, and C the centre.
Σελίδα 43 - ... section shall be parallel to the remaining side of the triangle. Let DE be drawn parallel to BC, one of the sides of the triangle ABC: then BD shall be to DA, as CE to EA. Join BE, CD; then the triangle BDE is equal...
Σελίδα 37 - ... the three interior angles of' a triangle are together equal to two right angles.
Σελίδα 39 - Hence it is plain that triangles on the same or equal bases, and between the same parallels, are equal, seeing (by cor.
Σελίδα 105 - The distance between two points on the surface of a sphere is the length of the minor arc of a great circle between them.