THE ENGINEER SERIES

THE GYROSCOPIC COMPASS
A NON-MATHEMATICAL TREATMENT

THE ENGINEER SERIES

THE
GYROSCOPIC COMPASS

A NON-MATHEMATICAL TREATMENT

BY

T. W. CHALMERS, B.Sc., A.M.I.Mech.E.
(On the Editorial Staff of “The Engineer”)

ILLUSTRATED

LONDON
CONSTABLE & COMPANY, LTD.
10 ORANGE STREET, LEICESTER SQUARE. W.C.
1920

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Printed in Great Britain

The chapters composing this book originally appearedas a series of articles in The Engineer during January,February, and March of the current year. The articleswere written in the belief that many readers wouldwelcome a clear and full, non-mathematical exposition ofthe gyroscopic compass, its theory and practical construction.The gyro-compass represents at once the mostinvolved and abstruse and the most important andvaluable of all the practical applications to which thegyroscope, so far, has been put. As a navigationalinstrument it is now in practically universal use in all thechief war navies of the world, and is to-day being adoptedby several important representatives of the mercantilemarine. Remarkable figures were shown to the authorrecently which demonstrated that not only was navigationby the gyro-compass much more accurate than bythe magnetic compass, but that the increased accuracyreduced the length of the voyage of a mercantile vesselto an extent that resulted in saving a quantity of fuelthe value of which on a single trip would go a considerableway towards meeting the extra first cost of the gyro-compass.Bearing these facts in mind the author fromthe outset endeavoured not only to dispense withmathematics but to avoid introducing anything exceptthe most familiar physical principles and conceptions, forhis object was to explain the mode of action of the gyrovi-compassfor the benefit primarily of the navigatingofficer—naval and mercantile. If some readers shouldfind the treatment in places unduly prolix, the authortrusts they will exercise leniency and regard the fault asbeing caused by the author’s unwillingness to take anyrisks in expounding a subject, no part of which can beunderstood incompletely without grave hurt to theunderstanding of the whole.

T. W. C.

London, May, 1920.

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