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PREFACE TO THE FIRST EDITION.
HAVING found, from experience, that the majority of Guide or Hand Books to the Local Marine Board Examinations are too copious and extensive, I have endeavoured in this publication to embrace, in as small a compass as possible, all those subjects which are necessary to be understood by Candidates before presenting themselves for Examination,
The whole of the Questions in the Twelve Papers are solved by NORIE'S EPITOME, that work being principally used by seafaring men; but I may remark, that I perfectly agree with a friend of mine, that there is too great a redundancy of Tables in NORIE, which has the effect of rendering Seamen careless and inaccurate, trusting too impli. citly to extraneous assistance, and thus the object is defeated which the Board of Trade has in view, namely, that they shall be able to compute for themselves.
In finding the true Altitude from the observed Altitude of the Sun's lower limb, ÑORIE's Table IX. has been used, which reduces the whole of the corrections into one, and which will be found to be within a very few seconds of the truth, and sufficiently accurate for all practical purposes.
The Rules, as well as the Blank Forms, of the different Problems, are given in order to show the pupil at once the form and the formula used in the solution of each Question.
I have not given any Courses to be corrected for Deviation in the Papers; but to supply the deficiency, there are a few examples at page 33, which will suffice if the pupil can solve them correctly.
A few Exercises on the Charts, for Masters and Mates, will, I think, prove useful. The Bearings and Distances of the principal Headlands, as well as those of the Lights, are taken from the Piloting Directions for the East Coast of England and the English and Bristol Channels, books which are indispensable to navigators in the British Seas.
To each of the Questions in the Papers are added the different parts of the solution, so that the pupil may more readily detect any error in the course of his work, before he arrives at the final answer.
I hope that this little volume will, in some measure, accomplish tho object for which it is intended, namely, to be a guide to mariners desirvus of acquiring a sound knowledge of navigation, which is essential to advancement in their vocation, and to which so many of our seafaring friends in the present day direct special attention. I would, in conclusion, recommend to them perseverance in their studies, remembering the exhortation,“ Whatsoever thy hand findeth to do, do it with thy might."
PREFACE TO THE SECOND EDITION.
THE extensive sale of the first edition of this work is a proof of its usefulness; and to make it still more valuable to the Officers and Seamen of the Mercantile Marine, I have added Examples of each of the different Problems; also the principal dangers in the Channel, with remarks on the Entrances to the different Ports.
PREFACE TO THE THIRD EDITION.
The two former editions of this “Guide” have received such a large demand, and proved (by testimonials) so useful in schools, that the Author has been induced to add much valuable information in the present edition. The article on the Navigation of the English Channel will, I know from experience, prove useful both to Masters and Mates who are about to pass the Local Marine Board for Certificates of Competency, and also to those who navigate the English Channel.
I have to express my thanks to Mr. J. Bolam, Head Master of the Board of Trade Nautical Schools, at Leith, for his article on the “ Barometer;" and if the rules laid down in it are strictly adhered to, much good may be done for the science of Meteorology, and for the safety of property under the charge of those in command.
The whole of the Questions in this edition are still worked by Norie's Tables; but if any other Nautical Tables are used, such as Riddle's, Thomson's, or Raper's, the answers obtained will be found to be within a few seconds of the answers given here, and sufficiently near either for examinations or practical purposes at sea.
Although the book is much enlarged, the publishers have determined to keep it at the same price, so that it may be within the reach of all who follow a seafaring life.
This work is now used in nearly all the Navigation Schools throughout the Kingdom ; and in placing this edition before the public, the author is convinced that it will receive even a larger amount of support than the two previous editions.