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A Rudimentary Treatise on Clocks, Watches and Bells for Public Project Gutenberg’s A Rudimentary Treatise on Clocks, Watches and Bells, by Edmund Beckett. This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.net Title: A Rudimentary Treatise on Clocks, Watches and Bells Author: Edmund Beckett Release Date: January 22, 2006 [EBook #17576] Language: English Character set encoding: TeX *** START OF THIS PROJECT GUTENBERG EBOOK CLOCKS, WATCHES, BELLS *** Produced by Robert Cicconetti, Laura Wisewell and the Online Distributed Proofreading Team at http://www.pgdp.net i Transcriber’s Notes: The original of this book had its table of contents, running headers, and headings in the text all independent. The table of contents given here is as in the original, as are the head- ings in the text. However, the PDF bookmarks reflect the structure of the headings in the text, and, owing to repagination, it has proved very difficult to match the running headers, although I have aimed to as far as possible. Some of the book’s headers seemed to refer to a figure on the page; these are preserved here as figure captions, which did not appear in the original. All page references, including those in the index, have been re- generated to point to anchors placed in the source text; in some cases their placement was ambiguous, but every effort has been made to place them directly beside the text referred to. Phrases such as “this figure” or “on the next page” have been left as in the original, but may no longer be accurate after repagination. However, I have ensured that a hyperlink is always given. Two pages of the original copy used had corners missing, therefore the words “see” on page 10 and “They” and “where” on page 11 are uncertain, and there could be another word following “languished” on page 21. On page 29 I have changed “signify” to “significantly” as suggested by the sense. In an equation on page 61 the l in the denominator had been printed as a /. The word “scrapewheel” on page 75 has been changed to “scapewheel”. Finally, the word “ex- plored” on page 97 had been printed as “exploded”. All of these words have been highlighted in the text like this , and also in the source file with two asterisks (**). A RUDIMENTARY TREATISE ON CLOCKS, WATCHES, & BELLS FOR PUBLIC PURPOSES BY EDMUND BECKETT, LORD GRIMTHORPE LL.D. K.C. F.R.A.S. PRESIDENT OF THE BRITISH HOROLOGICAL INSTITUTE, AUTHOR OF ‘ASTRONOMY WITHOUT MATHEMATICS,’ ETC. EIGHTH EDITION, MOSTLY REPRINTED FROM THE SEVENTH EDITION OF 1883, WITH A NEW PREFACE AND NEW LIST OF GREAT BELLS, AND AN APPENDIX ON WEATHERCOCKS WITH NUMEROUS ILLUSTRATIONS LONDON CROSBY LOCKWOOD AND SON 7 STATIONERS’ HALL COURT, LUDGATE HILL 1903 All Rights reserved by the Author D. VAN NOSTRAND COMPANY. PRINTED BY WILLIAM CLOWES AND SONS, LIMITED, LONDON AND BECCLES. PREFACE TO THE EIGHTH EDITION. There have been so many editions or reprints of this book (including the articles on Horology in two editions of the Encyclopædia Britannica) that I cannot count them rightly, especially as several were issued under my former names of Denison and Beckett (Lord Grimthorpe since 1886). At least, I suppose so. This is certainly, in substance, at least the tenth issue. The book led to my designing, either directly or indirectly, not only the Westminster and St. Paul’s clocks, and the great peal of bells there, but those of many other Cathedrals and Churches, as well as Town-hall, Railway-station, and others in several of our Colonies, by special request. As I did all that work gratuitously, I have no means of tracing them, or probably remembering the names of them all. I know that I once counted above forty. The Publishers have received from my friend Canon Nolloth, of Beverley Minster, some further information about Bells, which (as it could not be inserted in the stereotype plates) has been inserted, with some remarks of my own, as Addenda, at pp. 281–282. Canon Nolloth has also completed (pp. 278–280) my own last list of large bells in various countries. I have also added a short Appendix (p. 283) on Weathercocks. GRIMTHORPE. Batch Wood, St. Alban’s. May, 1903. ii PREFACE. As this is not unlikely to be the last time that I shall revise this book, considering my age and the number of copies printed in each edition of late (3000), and as I have had more leisure than for many years, I have endeavoured to make it as complete as possible, and have introduced more new matter and alterations than in any edition since the fourth. This was one of the first ‘Rudimentary Treatises,’ undertaken with great spirit by the late Mr. Weale, at the suggestion of my friend and connec- tion, Colonel Sir W. Reid, K.C.B., the author of the ‘Law of Storms,’ and the chief manager of the Exhibition of 1851, at the request of the Prince Consort; and 7000 copies were printed of the first edition. The articles on Clocks and Watches, but not on Bells, in the eighth and ninth editions of the Encyclopædia Britannica, were abridgments of this book, and therefore make this edition practically the ninth written by me. It should be understood that this professes to be a rudimentary treatise in the sense of teaching the principles of horology, and so much practical knowledge as may be useful both to clockmakers and to amateurs who wish to make, or direct the making of, their own clocks of superior character; and I have had abundant information that it has been useful in that way, besides vastly improving the general character of public clocks especially, in all the English-speaking world, and wherever large English clocks go. Nobody can learn the details of watchmaking from a book, and at any rate in no such space as could be given to it in a volume like this. There have been, from time to time, useful letters on various details of the art in the English Mechanic and the Horological Journal. I have never heard of any amateur taking up watchmaking as many do the making or designing of clocks; and it depends much more on manual dexterity and practice. Therefore that part of the book deals more with principles than with working details. I leave the chapter on Bells to speak for itself, as the only English treatise on their proper construction, shape, composition, and the best modes of hanging; and as the result of long experience and many special experiments, iii PREFACE. iv to revive an art which had sunk to a lower ebb thirty or forty years ago than it had ever reached in the thousand years or more since large bells were first made. E. B. Batch Wood, St. Alban’s, and 33, Queen Anne Street, W: Jan, 1883. CONTENTS. page MEASURES OF TIME 1 Sidereal day 1 Solar day and transit instrument 2 Mean time and year 2 Equation of time 3 Astronomical and civil day 4 Table of equation of time 5 Sidereal time 4 Table of local time 6 Sidereal and mean dials useless 6 Sun-dials 8 Meridian dial simplest fig. 1 9 Dipleidoscope fig. 2 10 Water and sand clocks 11 Clocks, History of 12 Early English ones 13 Common clock train figs. 3 and 4 14, 15 Fan-fly instead of pendulum 17 Conical pendulum, or governor 17 Relation of length to gravity 17 Barker’s mill governor 19 Revolving pendulum fig. 5 18 Balance-wheel, earliest fig. 6 20 Pendulums, history of 21 Crown-wheel escapement fig. 7 22 Cycloidal theory fig. 8 23 Cheeks, a failure 24 Circular error 24 v CONTENTS. vi Mathematics of pendulum theory 25 Lengths of various pendulums 25 Centre and radius of oscillation 26 Moment of inertia 26 Standards of length 27 French metre a bad measure 28 Egyptian and Jewish cubits 28 Short and slow pendulums 29 Shape and material of pendulums 29 Suspension of them fig. 9 31 Where they may be 32 Pendulum springs 33 Regulation of clocks 34 Compensated pendulums 36 Table of expansions and specific gravities 36 Zinc and steel pendulum 37 Weights of some 39 A mistake about compensation 39 Wood and lead compensation 40 Wood, zinc, and lead 41 Smeaton’s glass pendulum 42 Compound bar compensation fig. 10 43 Homogeneous and Ellicott’s fig. 11 44 Mercurial; Baily’s mistake 45 A new kind of jar fig. 12 46 Cast-iron jars best; calculation for 47 Barometric error and compensation 48 Westminster pendulum fully compensated 49 Air-tight clock cases 50 Compensation by thermometer tube 50 Greenwich plan 51 Anchor pallets fig. 13 53 Harrison’s recoil escapement 54 Clocks out of beat 54 Dead escapements fig. 14 56 General theory of 55 Importance of dead friction 57 Sir G. Airy’s calculations 59 His conclusion erroneous 62 Proper construction 62 Half-dead escapement 63 CONTENTS. vii Loseby’s isochronal spring fails 63 Large and small arcs 64 Value of firm fixing of pendulum 64 Materials for scapewheels 65 Weight of them 65 Pallets should be short 66 Rules for construction 66 Pin-wheel dead escapement fig. 15 69 Pin pallets 68 Single-pin escapement fig. 16 70 Sir E. Beckett’s three-legged one fig. 17 71 Another form of it fig. 18 72 Detached escapements, Airy’s fig. 19 73 Beckett’s fig. 20 74 Single-beat escapements waste no force 75 Gravity escapements, value of 75 Mudge’s fig.
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