LONDON:

ROBSON AND SONS, PRINTERS, PANCRAS ROAD, N.W.

PREFACE.

In the present edition the Author has adapted the rules not only to the Tables of Dr. Inman (the most comprehensive and useful yet published), but also to those in more general use, such as Riddle's, Norie's, &c. The student will therefore find now no difficulty in working out the examples contained in the book by any of the above tables. In the last edition of the Author's work on Plane and Spherical Trigonometry, rules are also given depending on the common tables of sines, &c., as well as on the valuable table of haversines contained in Inman's Tables.

Langstone House, Havant,

Feb. 1, 1870.

Definitions

CONTENTS.

NAVIGATION.

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Mercator's Chart

Given lat. from and lat. in, to find true diff. lat.

Given lat. from and lat. in, to find merid. diff. lat.

Given lat. from and lat. in, to find middle lat.

Given long. from and long. in, to find diff. of long.

Given lat. from and true diff. lat., to find lat. in

Given long. from and diff. long., to find long. in

Trigonometrical ratios

Nautical problems solved by Trigonometry

Description of compass and log. line

Bearings or angular distances by compass.

Nautical problems solved by Trigonometry, and also by construction

Correction of courses

Given compass course and variation, to find true course

Deviation of compass from local attraction

Given compass course, variation, and deviation, to find true course

Given true course, variation, and deviation, to find compass course

Given compass course, variation, deviation, and leeway, to find true

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I. Given lat. and long. in, to find course and distance (by meridional

parts).

parts)

II. Given course and distance, to find lat. and long. in (by meridional

IV. Given course and distance, to find lat. and long. in (by middle lat.)
V. Parallel sailing: to find course and distance

III. Given lat. and long. in, to find course and distance (by middle

lat.).

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RULE

VI. Parallel sailing: to find lat. and long. in

Application and use of formulæ in Navigation

VII. The day's work: to find place of ship

(For examples of day's work, see Examination Papers at
end of the book.)

NAUTICAL ASTRONOMY.

Astronomical and Nautical terms and definitions

Rules in Nautical Astronomy.

I. Given civil or nautical time, to find astronomical time

II. Given astronomical time, to find civil or nautical time

III. To reduce degrees into time

IV. To reduce time into degrees

To find the time at any place, having given the Greenwich

time and longitude .

V. To find the Greenwich date (first method)

VI. To find the Greenwich date (second method).

Explanation and use of the Nautical Almanac.

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VII. To take out of the Nautical Almanac for any given time
the sun's declination (first method)

VIII. To take out the sun's declination (second method)

IX. To take out the equation of time

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XII. To take out the moon's declination and right ascension

XIII. To take out the right ascension of the mean sun

XIV. To take out the lunar distance for any given time at

Greenwich

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XI. To take out the sun's right ascension

XV. To find the time at Greenwich corresponding to a given

lunar distance.

To take out a planet's right ascension and declination

Equation of second differences

Preliminary Rules and Problems in Nautical Astronomy.

XVI. Given mean solar time and the equation of time, to find

apparent solar time and the converse

XVII. Given mean solar time, to find sidereal time

XVIII. Given apparent solar time, to find sidereal time

XIX. To find what heavenly body will pass the meridian the