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 Otf THE 
 
 consteuction of looks. 
 
LONDON: 
 
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 Great New Street and Fetter Lane, 
 
RUDIMENTARY TREATISE 
 
 ON THE 
 
 CONSTRUCTION OF 
 
 EDITED BY 
 
 LOCKS. 
 
 CHARLES TOMLINSON. 
 
 “ II n’y a point de machines plus communes que ies serrures : elles sont assez 
 composdes pour meriter le nom de machine; mais je ne sais s’il y en a qui 
 soient aussi pen connues par ceux qui ies emploient. II est rare qu’on sache en 
 qnoi consiste la hont6 d’une serrure, le degre de stlrete qu’on peut s’en promettre. 
 Leur exterieur est presque la seule chose ii quoi l’on s’arrete. Les usages im- 
 portans auxquels elles sont employees devraient cependant exciter la curiositd 
 h les eonnaitre, ai la curiosite dtait toujours excitee raisonnahlement.”— M. de 
 Reaumtje, “Des Serrures de toutes les espices,” forming the fifth chapter of M. 
 Duhamel’s Treatise “ Art du Serrurier in the “ Descriptions des Arts et Metiers 
 faites <m approuvies par Messieurs de VAcadAmie Royale des Sciences" 
 
 LONDON: 
 
 JOHN WEALE, 59 HIGH HOLBORN. 
 
 MT)CCCT,TTT. 
 
“ Thei’e are no machines more common than locks: they are sufficiently com¬ 
 plex to merit the name of machine; but I know of no others the structure of 
 which is so little understood by those who use them. It is rare to find any one 
 who knows wherein the goodness of a lock consists, or the degree of security that 
 he can attach to it. The outside of a lock is usually all that attracts attention. 
 Doubtless the important uses to which locks are applied would excite curiosity 
 respecting their structure, if curiosity were always excited for worthy objects.” 
 —M. de Reacmub. 
 
 THE GETTY CENTER 
 
 LIBRARY 
 
PREFACE, 
 
 The reader is entitled to know the origin of the small work which 
 he holds in his hands. 
 
 In August 1852, being about to write a short article on 
 Locks for a Cyclopaedia of Useful Arts, of which I am the editor, 
 I consulted my esteemed and lamented friend, the late Professor 
 Cowper, of King’s College, as to the desirability of explaining to 
 the general reader the defects of some of our English locks, which, 
 previous to the celebrated “lock controversy” of 1851, had borne 
 a high character for skilful construction, beauty of workmanship, 
 and undoubted security. Professor Cowper expressed his strong 
 conviction that by exposing the defects of our locks, the cause of 
 mechanical science, as well as the public in general, would be 
 benefited; that if our locks were defective, inventors would be 
 stimulated to supply the defects, and the art of the locksmith 
 would be raised accordingly. He considered that Mr. Hobbs had 
 made a considerable step in advance in the constructive details of 
 his art, not only in having detected the weak points of some of 
 our best English locks, but also in having introduced two or three 
 new locks, which appeared to be more secure than any of those 
 previously produced. Professor Cowper gave me an introduction 
 to Mr. Hobbs, who placed at my disposal a variety of literary 
 materials relating to the history and construction of locks, and 
 stated his intention at some future time of bringing out a small 
 book on the subject, if he could meet with a publisher. I recom¬ 
 mended him to offer the work to Mr. Weale, for insertion in his 
 series of Rudimentary Works. This was accordingly done, and I 
 was invited to prepare the work ; but as my engagements did not 
 leave me sufficient leisure to write the book, I requested my friend 
 Mr. George Dodd to put the materials together, and to search for 
 
VI 
 
 PREFACE. 
 
 more. Mr. Dodd acceded to my request; and having completed 
 his part of the work, I subjected it to a careful revision, and added 
 various details which seemed to he necessary to completeness, at 
 least so far as the narrow limits of a small rudimentary work would 
 admit of completeness. The manuscript was then sent to press : 
 each sheet as it was received from the printer was submitted to 
 Mr. Hobbs, who read it with care, and made his annotations and 
 corrections thereon. Mr. Hobbs and I then had a meeting, when 
 the additions and corrections were read and discussed, and ad¬ 
 mitted or rejected as the case might be. The sheet having been 
 thus corrected was sent to press. 
 
 It should also be stated that, during the progress of the work, 
 Mr. Weale, at my request, wrote to Messrs. Bramah, and also to 
 Messrs. Chubb, informing them that a Rudimentary Treatise on 
 the Construction of Locks was being prepared, and requesting 
 them to state in writing what alterations or improvements they 
 had made in their locks since the date of the Great Exhibition. 
 The communications which we have received from these celebrated 
 firms are inserted verbatim , in their proper places, in the present 
 work. 
 
 Such is the mode in which this small volume has been prepared. 
 I have endeavoured to perform an editor’s duty conscientiously, 
 without entertaining the feeling of a partisan in the matter. My 
 chief object in superintending the production of this book (an ob¬ 
 ject in which the Publisher fully participates) is to advance the 
 cause of mechanical science, and to supply a deficiency in one of 
 the most interesting portions of its English literature. 
 
 C. TOMLINSON. 
 
 Bedford Place, Ampthill Square, 
 
 July 1853. 
 
ADVERTISEMENT. 
 
 The first edition of this volume, though at the date of 
 its appearance co-ordinating with the state of know¬ 
 ledge of the period, and containing matter well arranged 
 and lucidly described—as must have been expected 
 from the reputation of its author—had, through the 
 lapse of the few intervening years, inevitably become 
 somewhat behind the state of the art of which it treats 
 —one which is daily receiviug the attentive considera¬ 
 tion of many skilful men, and occasional marked im¬ 
 provements. Amongst those of later years none are 
 more noteworthy than the locks patented by Mr. Fenby, 
 of Birmingham ; of these an account, with accurate 
 illustrations, for which the drawings are supplied by 
 the inventor, is now added,—together with a brief 
 essay upon the important but popularly ill-understood 
 subject of iron safes. 
 
 ROBERT MALLET. 
 
 April, 1868 . 
 
In reference to Mr. Smyth’s letter, which is given at 
 pp. 130, 131, that gentleman is desirous to state that 
 it was in consequence of the defects there pointed out 
 that Mr. Hobbs was enabled to pick the Bramah lock 
 operated upon, which had been manufactured forty 
 years previously, when the sliders were made of iron 
 instead of steel as they now are, and yet, notwith¬ 
 standing that and the other defects pointed out, it 
 took Mr. Hobbs sixteen days to pick it. In proof of 
 the security of the Bramah lock, Mr. Smyth mentions 
 that Mr. Hobbs’s best workman failed in picking an 
 ordinary 3-inch Bramah box lock; and that a person 
 in the employ of Messrs. Johnson and Ravey, of Con¬ 
 duit Street, failed also in his attempt to pick a 6-inch 
 cellar-door lock, though he had the lock in his posses¬ 
 sion for twelve months, employing his evenings in 
 making instruments and trying to pick it. Mr. Smyth 
 contradicts the statement made at page 128, that the 
 new lock was removed from the window through any 
 fear of its being opened. On the contrary, it was put 
 up especially to afford an opportunity for Mr. Hobbs 
 to make, if he thought fit, another trial, and it re¬ 
 mained in the window four months. The sole cause of 
 its removal was to stop the impertinent applications of 
 men and boys, which interfered too much with the 
 general business of the firm. 
 
CONTENTS. 
 
 CHAP. PAGE 
 
 I. On Locks and Lock-literature. 1 
 
 II. Ancient Locks : Grecian, Homan, Egyptian. 8 
 
 III. Lock classification. The Puzzle-Lock and the Dial-Lock 16 
 
 IV. Warded Locks, with their varied appendages .... 27 
 
 V. On Tumbler or Lever Locks.43 
 
 VI. The Bramah Lock.64 
 
 VII. American Locks.'82 
 
 VIII. The Lock Controversy: previous to the date of the Great 
 
 Exhibition.102 
 
 IX. The Lock Controversy: during and since the time of the 
 
 Great Exhibition.115 
 
 X. Effects of the Great Exhibition of 1851 in improving Eng¬ 
 lish Locks.140 
 
 XI. The Lock and Key Manufacture.154 
 
 XII. English Patents for Locks. Aubin’s Lock Trophy. Con¬ 
 
 clusion .164 
 
 Appendix. 
 
 XIII. On an Improved Construction of Lock and Key : Fenby’s 
 
 Adytic Lock.176 
 
 XIV. Fenby’s Stop Lock.193 
 
 XV. Note upon Iron Safes.201 
 

ON THE 
 
 CONSTRUCTION OF LOCKS. 
 
 CHAPTER I. 
 
 ON LOCKS AND LOCK-LITERATURE. 
 
 The manufacture of locks, and a consideration of the me¬ 
 chanical principles involved in their construction and security, 
 have never yet been treated with any degree of fulness in an 
 English work. Lock-making has occupied a large amount of 
 ingenuity, and lock-patents have been obtained in considerable 
 number, though not always, we are satisfied, with a commen¬ 
 surate return for the expense incurred,—but lock-philosophy 
 (if so it may be designated) has not been largely attended to. 
 
 And yet it may safely be said that much which is both 
 mechanically and commercially important is comprised in a 
 lock. Every improvement in the manufacture of iron, steel, 
 and brass—that is, in the tool-making and machine-making 
 processes—may be made to reflect its light on the lock- 
 manufacture ; the stamping, the casting, the planing, the 
 slotting, the screw-cutting, the polishing of metals,—all, in 
 proportion as they are improved, impart some of their aid 
 to the lock-maker. Then, in the finer kinds of locks, the 
 works are so delicate as to approach to the nicety of clock¬ 
 work; thereby combining the manipulative skill of a talented 
 
 B 
 
2 
 
 ON LOCKS. 
 
 artisan with the rougher mechanical work of the smith. The 
 principles of mechanical science are also appreciated by many 
 lock-makers. The lever, the inclined plane, the eccentric, the 
 cam, the screw, the .wheel and pinion, the ratchet, the spring, 
 — all are brought to bear on the internal mechanism of locks, 
 frequently in many novel combinations. 
 
 The commercial importance of locks — though of course 
 never seriously questioned when once fairly brought before 
 one’s attention—has been recently rendered so apparent as to 
 have risen to the position of a public topic. If a strong room, 
 containing gold and silver, notes and bills, books and papers—if 
 such a room be necessarily shielded from intrusion, it becomes 
 no less necessary that the shield should be really worthy of 
 its name, trusty and reliable: a good lock is here nearly as 
 indispensable as a faithful cashier. And without dwelling on 
 such an auriferous picture as a room full of gold, we shall 
 find ample proof of the commercial importance of lock-making 
 in the ordinary circumstances by which we are every day 
 surrounded. Until the world becomes an honest world, or 
 until the honest people bear a larger ratio than at present to 
 the dishonest, the whole of our movables are, more or less, at 
 the mercy of our neighbours. Houses, rooms, vaults, cellars, 
 cabinets, cupboards, caskets, desks, chests, boxes, caddies,— all, 
 with the contents of each, ring the changes between meum and 
 tuuni pretty much according to the security of the locks by 
 which they are guarded. 
 
 A commercial, and in some respects a social, doubt has 
 been started within the last year or two, whether or not it is 
 right to discuss so openly the security or insecurity of locks. 
 Many well-meaning persons suppose that the discussion respect¬ 
 ing the means for baffling the supposed safety of locks offers 
 a premium for dishonesty, by shewing others how to be dis¬ 
 honest. This is a fallacy. Eogues are very keen in their 
 profession, and know already much more than we can teach 
 them respecting their several kinds of roguery. Rogues knew 
 a good deal about lock-picking long before locksmiths dis- 
 
ON LOCKS AND LOCK-LITERATURE. 
 
 3 
 
 cussed it among themselves, as they have lately done. If a 
 lock—let it have been made in whatever country, or by 
 whatever maker—is not so inviolable as it has hitherto been 
 deemed to be, surely it is to the interest of honest persons 
 to know this fact, because the dishonest are tolerably certain 
 to be the first to apply the knowledge practically; and the 
 spread of the knowledge is necessary to give fair play to those 
 who might suffer by ignorance. It cannot be too earnestly 
 urged, that an acquaintance with real facts will, in the end 
 he better for all parties. Some time ago, when the reading 
 public was alarmed at being told how London milk is adul¬ 
 terated, timid persons deprecated the exposure, on the plea 
 that it would give instructions in the art of adulterating milk- 
 a vam fear —milkmen knew all about it before, whether they 
 practised it or not; and the exposure only taught purchasers 
 the necessity of a little scrutiny and caution, leaving them to 
 obey this necessity or not, as they pleased. So likewise in 
 respect to bread, sugar, coffee, tea, wine, beer, spirits, vinegar, 
 cheap silks, cheap woollens—all such articles as are suscep¬ 
 tible of debasement by admixture with cheaper substances— 
 much more good than harm is effected by stating candidly 
 and scientifically the various methods by which such debase¬ 
 ment has been, or can be produced. The unscrupulous have 
 the command of much of this kind of knowledge without our 
 aid ; and there is moral and commercial justice in placing on 
 their guard those who might possibly suffer therefrom. We 
 employ these stray expressions concerning adulteration, de¬ 
 basement, roguery, and so forth, simply as a mode of illus¬ 
 trating a principle—the advantage of publicity. In respect 
 to lock-making, there can scarcely be such a thing as dis¬ 
 honesty of intention: the inventor produces a lock which he 
 honestly thinks will possess such and such qualities; and he 
 declares his belief to the world. If others differ from him in 
 opimon concerning those qualities, it is open*to them to say 
 so; and the discussion, truthfully conducted, must lead to 
 public advantage: the discussion stimulates curiosity, and the 
 
4 
 
 ON LOCKS. 
 
 curiosity stimulates invention. Nothing but a partial and 
 limited view of the question could lead to the opinion that 
 harm can result: if there be harm, it will be much more than 
 counterbalanced by good. 
 
 The literature of lock-making is, as we have implied, very 
 scanty, both in England and America. The French and Ger¬ 
 mans, though far below our level as lock-makers, are very supe¬ 
 rior to us in their descriptions of the construction and manu¬ 
 facture of locks. Take, for instance, the French treatise pub¬ 
 lished more than eighty years ago by the Academie des Sciences, 
 and forming part of a folio series of manufacturing treatises, 
 illustrated very fully by engravings. It is worth while to exa¬ 
 mine this work, to see how minutely and faithfully the writers 
 of such treatises performed their task nearly a century ago. 
 The Art du Serrurier, with the distinguished name of M. Du- 
 hamel du Monceau as the author or editor, was published in 
 1767. It occupies 290 folio pages, and is illustrated by 42 
 folio plates. The first chapter gives us an introduction and 
 general principles, in which the choice and manipulation of 
 materials are touched upon; the different qualities of iron and 
 steel; and the processes of forging, founding, welding, stamp¬ 
 ing, filing, polishing, &c. In the copper-plates represent¬ 
 ing these smiths’ operations and the tools employed,* there 
 is a smithy, with about a dozen smiths engaged in all these 
 various occupations, with stockings down, and a due amount 
 of workshop slovenliness. The next chapter takes us into 
 what may perhaps be called “ smith’s work in general,” or 
 at least it treats of the manufacture of various kinds of iron¬ 
 mongery for doors, windows, and house-fittings generally. 
 Then the third chapter treats of “ smith’s work which serves 
 for the security of houses,” consisting of railings, palings, 
 bars, and gates of various kinds — such at least as are made 
 of iron. In chapter four we have a notice of such kinds of 
 
 * It is worthy of remark, that the tools described are the same as those 
 which are used by the locksmith at the present day; shewing how little 
 improvement has been made in the means of producing locks. 
 
ON LOCKS AND LOCK-LITERATURE. 
 
 5 
 
 smith s work as relate to the fastenings for doors, windows, 
 closets, chests, &c.; such as hinges, hasps, latches, bolts, and 
 other contrivances less complex than an actual lock. This 
 brings us, by a natural transition, to locks in general, which 
 form the subject of chapter five, to which is attached the illus¬ 
 trious name of M. de Reaumur as the author. Here are given 
 a hundred folio pages of description, illustrated by twenty folio 
 plates relating to locks, lock-making, and locksmiths. The 
 sixth chapter relates to the iron-work of carriages, or the 
 labours of the coachsmitlis; while chapter seven, to wind up 
 the work, relates to bell-hanging. 
 
 That chapter of the work which has reference to locks is 
 the only one with which we have to do here. It is arranged 
 m a systematic manner, beginning with the simpler locks, 
 without wards or tumblers, and proceeding thence to others of 
 moie complex construction. The period at which the work 
 was written was too early to lead us to expect to find a 
 tumbler-lock described and delineated: there are, however, 
 numerous examples of single tumbler-locks, many of them of 
 great ingenuity. The use of multiple bolts, that is, of many 
 bolts shot at once by one action of the key, seems to have been 
 familiar enough to the locksmiths of .those days. One lock re¬ 
 presented is remarkable; it is attached to a strong and ponder¬ 
 ous coffer or chest. The chest is open; and the whole under 
 or inner surface of the cover is seen to be occupied by a lock 
 of intricate construction; there are no less than twelve bolts, 
 three on each long side, one on each short side, and one in 
 each corner; these bolts are so placed as to catch under a pro¬ 
 jecting rim fixed round the top of the coffer. The collection 
 of keys, exhibited on a separate plate, is remarkable for the 
 great variety of forms given to them. We shall by and by 
 copy some of the drawings of this curious work. 
 
 It was to be expected that in the Encyclopedic Methodique, 
 published in the same country and in the same century, the 
 locksmith s art would be treated at some such length as in the 
 work just described. Among the two hundred volumes of 
 
6 
 
 ON LOCKS. 
 
 which the Cyclopedic consists, several are devoted to arts and 
 manufactures; and one of them contains the article in question. 
 It occupies 168 quarto pages, and is illustrated by 35 copper¬ 
 plate engravings, shewing in detail not only the parts of vari¬ 
 ous locks, but the tools used by the lockmaker. It is proper, 
 however, to remark, that much of the letterpress and many 
 of the plates relate to smith’s work generally, and not ex¬ 
 clusively to lock-work; the French name serrurerie being 
 applied not only to lock-making, but to most of the smith’s 
 work required in dwelling-houses. This affords, indeed, a 
 striking illustration of the fact, that until lately a lock-maker 
 has been regarded rather as a smith than as a machinist, 
 rather as a forger and filer of pieces of iron, than as a 
 fabricator of delicate mechanism. One of the most curious 
 features in this treatise is a vocabulary, containing, in alpha¬ 
 betical arrangement, a minute account of all the French tech¬ 
 nical terms employed in the locksmith’s art. This vocabulary 
 alone occupies 38 quarto pages. 
 
 The Germans, like the French, bestow great attention on 
 their treatises relating to the manufacturing arts. Some of 
 these are, indeed, worked up to a degree of minuteness 
 which would seem superfluous, where little distinction is 
 drawn between the importance of fundamental principles and 
 that of mere technical details. Locks have had their due 
 share. The article on locks in Prechtl’s Technological En- 
 cyclopcedia written by Karmarsch, and published in 1842, 
 occupies about 140 pages. Locks are very minutely clas¬ 
 sified by the author, according to their purposes and their 
 modes of action, and are illustrated by many plates. One of 
 his classifications is into German, French, and Bastard locks, 
 referring in part to the extent to which the key turns round 
 in the lock; and the last of the three having an intermediate 
 character between the other two. After treating of the ordi¬ 
 nary warded locks, he comes to the combination principle; 
 and it is profitable here to notice, how well the works of our 
 machinists are understood on the continent, when they have 
 
ON LOCKS AND LOCK-LITERATURE. 
 
 7 
 
 any thing to recommend them; there are a dozen closely 
 printed pages devoted to a minute description of Bramah’s 
 invention, with all the separate parts illustrated by copper¬ 
 plate engravings. After this comes a more general account 
 of the details and manufacture of locks, similarly illustrated 
 by engravings. 
 
 _ Whatever may be the merits of the different articles re¬ 
 lating to locks in the various English cyclopedias, there are 
 none approaching in length to the article in Prechtl’s work. 
 But when we consider that Prechtl devotes twenty large vol¬ 
 umes to technological or manufacturing subjects, he is of 
 course able to devote a larger space to each article than is 
 given in English works. Both in England and in America, 
 men are more disposed to do the work than to describe it 
 when done. In the Encyclopedia Britannica , in Rees’ Cyclo¬ 
 pedia, in Hebert’s Engineers' and Mechanics' Cyclopedia, in 
 the Encyclopedia Metropolitana, in the Penny Cyclopedia, ’and 
 in other similar works, locks are described as well as can 
 be expected within the limits assigned to the articles. Mr. 
 Lramahs essay on locks, and on his own lock in particular, 
 is one of the few English pamphlets devoted expressly to this 
 subject. An excerpt from the proceedings of the Institute of 
 Civil Engineers, in 1851, gives an interesting paper on locks 
 by Mr. Chubb ; and shorter reports of papers and lectures 
 have been published in various ways. Perhaps the best ac¬ 
 count of locks which we have, considering the limited space 
 within which a great deal of information is given in a very 
 clear style, is that contained in Mr. Tomlinson’s Cyclopedia of 
 Useful Arts. J 
 
8 
 
 ON LOCKS. 
 
 CHAPTER n. 
 
 ANCIENT LOCKS : GRECIAN, ROMAN, EGYPTIAN. 
 
 Locks and door-fastenings have not, until modern times, been 
 susceptible of any classified arrangement according to their 
 principles of construction. They have been too simple to re¬ 
 quire it,and too little varied to permit it. That some such fast¬ 
 enings must be employed wherever doors of any kind are used 
 is sufficiently apparent; and there is a little (though only a 
 little) information obtainable, which shews the nature of the 
 fastenings adopted in early times. The bolt, the hasp, the chain, 
 the bar, the latch, the lock, all were known, in one or other of 
 their various forms, in those ages which we are accustomed to 
 consider classical. Travellers, generally speaking, do not de¬ 
 scend to locks, or rather they do not think about them ; 
 otherwise they might have collected much that would have 
 been novel and applicable to the present work; and, indeed, 
 there is some ground for the assertion, that a notice of th§ 
 door-fastenings of all nations would reveal to us something 
 of the social and domestic habits of various members of 
 the great human family. Be this as it may, however, we 
 may profitably make a little inquiry into the locks of ancient 
 times. 
 
 In the volumes of Lardner’s Cyclopaedia relating to the 
 “ Manners and Customs of the ancient Greeks and Romans,” 
 we do not find any mention of the kinds of locks used by those 
 nations ; but the author, while describing the houses, says :— 
 
 “ Doors turned anciently upon large pivots in the centre, let 
 into sockets in the lintel and threshold, so that one of the sides 
 opened inwards, the other outwards ; and Plutarch gives the 
 following curious reason why persons were to knock and 
 
9 
 
 ANCIENT LOCKS : GRECIAN, ROMAN, EGYPTIAN. 
 
 alarm the porter, viz. lest the visitor entering unawares 
 should surprise the mistress or daughter of the family busy or 
 undressed, or servants under correction, or the maids quarrel¬ 
 ing. As the visitors had thus the power (if permitted so to 
 do) to open the outer door of a house, it would appear that 
 very little in the nature of a lock was employed under ordi¬ 
 nary circumstances, unless indeed it were a mere latch. In 
 respect to Roman houses it is stated, that “ the doors revolved 
 upon pivots, which worked in a socket below, and were fast¬ 
 ened by bolts which hung from chains.” There is no mention 
 of locks here. Mr. St. John, in his work on the same subject, 
 says . The street-door of a Grecian house, usually, when 
 smgle, opened outwards ; but when there were folding-doors 
 they opened inwards, as with us. In the former case it was 
 customary, when any one happened to be going forth, to knock, 
 or call, or ring a bell, in order to warn passengers to make 
 way.” After describing the various kinds of wood of which 
 the doors were made, he proceeds : “ The doors at first were 
 fastened by long bars passing into the wall on both sides ; and 
 by degrees smaller bolts, hasps, latches, and locks and keys, 
 succeeded. For example, the outer door of the thalamos in 
 Homer was secured by a silver hasp, and a leathern thong 
 passed round the handle, and tied, perhaps, in a curious knot. 
 
 Mr. Yates, in a learned article on this subject in Smith’s 
 Dictionary of Greek and Roman Antiquities, collects numerous 
 details scattered through various early writers. We will string 
 together a few of these details, so far as they have any relation 
 to the fastenings of doors. The outer door of a Roman house 
 was generally called janua; whereas the inner doors were 
 called ostia. The doorway, when complete, consisted of four 
 indispensable parts—the threshold or sill, the lintel, and the 
 two jambs. The threshold, on which the feet trod, was often 
 regarded with a kind of superstitious reverence ; the lintel, 
 which crossed the doorway at the top, having a considerable 
 superincumbent weight to bear, was usually made of one 
 piece of timber or stone of great strength ; the jambs, or side 
 
 b 2 
 
10 
 
 ON LOCKS. 
 
 uprights, were also made in one piece each. The doorway, in 
 every building of the least importance, contained two doors 
 folding together; even the internal doors had their bivalve con¬ 
 struction. But in every case each of the two valves was unde 
 enough to allow persons to pass through without opening the 
 other ; in some cases even each valve was double, so as to fold 
 like our window-shutters. These doors, or valves, were not 
 hinged to the side-posts, as with us, but were, as has already 
 been stated, pivoted to the lintel above and the threshold be¬ 
 low. The fastening usually consisted of a bolt placed at the 
 base of each valve or half-door, so as to admit of being pushed 
 into a socket made in the sill to receive it. The doorways in 
 some of the houses at Pompeii still shew two holes in the sill, 
 corresponding to the bolts in the two valves. At night, the 
 front door of the house was further secured by means of a 
 wooden and sometimes an iron bar placed across it, and in¬ 
 serted into sockets on each side of the doorway ; hence it was 
 necessary to remove the bar in order to open the door. 
 Chamber-doors were often secured in the same manner. In 
 the Odyssey there is mention of a contrivance (adverted to by 
 Mr. St. John) for bolting or unbolting a door from the out¬ 
 side ; it consisted of a leather thong inserted through a hole in 
 the door, and by means of a loop, ring, or hook, capable of 
 taking hold of the bolt so as to move it in the manner re¬ 
 quired. We have here evidently the elements of a more com¬ 
 plete mechanism ; for the bolt was a rude lock in the same 
 degree that the thong was a rude key. That the Romans 
 afterwards had real locks and keys is clear; for the keys found 
 at Herculaneum and Pompeii, and those attached to rings, 
 prove that a kind of warded lock must have been well known.* 
 There are the remains of a tomb at Pompeii, the door of which 
 is made of a single piece of marble, including the pivots, which 
 were encased in bronze, and turned in sockets of the same 
 metal; it is three feet high, two feet nine inches wide, and 
 
 * An examination of the Roman keys in the British Museum sufficiently 
 attests this fact. 
 
11 
 
 ANCIENT LOCKS * GRECIAN. ROMAN, EGYPTIAN. 
 
 four and a quarter inches thick ; it is cut in front to resemble 
 panels, and thus approaches nearer in appearance to a modern 
 wooden door ; and it was fastened by some kind of lock, traces 
 of which still remain. 
 
 The same facts frequently become more clear when de¬ 
 scribed in different words by different writers. We shall 
 make use of this circumstance. Mr. Donaldson, in his Essay 
 on Ancient Doorways , presents us with details which illustrate 
 many of the foregoing remarks. “ Homer describes the trea¬ 
 sures and other valuable objects (mentioned in the Odyssey) 
 as being kept in the citadel, secured merely by a cord intri¬ 
 cately knotted. This, of course, was soon found to be a very 
 msufficient protection, and therefore a wooden bar was adopted 
 inside the doors of houses, to which it was attached by an iron 
 latch, fastened or removed by a key adapted to it; this key 
 was easily applied from within; but in order to get at it from 
 without, a large hole was made in the door, allowing the intro¬ 
 duction of the hand, so as to reach the latch and apply the 
 key. The lock called the Lacedaemonian, much celebrated by 
 ancient writers, was invented subsequently; it was especially 
 fitted for the inner chambers of houses, the bar fastenings con¬ 
 tinuing to be employed for closing the outer doors of dwellings 
 and the entrance-gates to cities. The Lacedaemonian lock did 
 not require a hole to be made in the door, for it consisted of 
 a bolt placed on that side of the entrance-door which opened, 
 and on the inside of a chamber-door. When a person who 
 was outside wished to enter, it was necessary for him to in¬ 
 sert the key in a little hole and to raise the bolt; and in time 
 this species of fastening was improved by the insertion of the 
 bolt in an iron frame or rim permanently attached to the door 
 by a .chain, and fastening the door by the insertion of the hasp, 
 through the eye of which was forced the bolt inside the lock 
 by applying the key.” After quoting a Latin sentence from 
 Varro in elucidation of his subject, Mr. Donaldson proceeds to 
 observe, that for the most part the locks of the ancients were 
 different in principle from those of modern days, not being in- 
 
12 
 
 ON LOCKS. 
 
 serted or mortised into the doors, nor even attached except by 
 a chain; they were, in fact, padlocks. 
 
 One of the passages in the Odyssey alluding to the primi¬ 
 tive mode of fastening the valves or folding-doors of a house 
 runs thus :— 
 
 “ Whilst to his couch himself the prince addressed. 
 
 The duteous nurse received the purple vest: 
 
 The purple vest with decent care disposed. 
 
 The silver ring she pulled, the door reclosed ; 
 
 The bolt, obedient to the silken cord. 
 
 To the strong staple’s inmost depth restored. 
 
 Secured the valves.” 
 
 Most of the other great nations of antiquity resembled 
 either the Egyptians or the Greeks and Romans, more or less 
 closely, in their domestic and domiciliary arrangements ; or, 
 at any rate, so far as such humble matters as locks and keys 
 are concerned, we need not seek far from those nations for 
 examples. The Nineveh and other Assyrian explorations 
 have, however, revealed many curious and unexpected facts ; 
 from the temples and the palaces we may by and by pene¬ 
 trate into the houses and rooms of the citizens sufficiently to 
 know how their doors were fastened. In the mean time 
 ancient Egypt awaits our notice. 
 
 Sir J. Gardner Wilkinson, in his Manners and Customs of the 
 Ancient Egyptians , gives the following information concerning 
 the doors and door-fastenings of that remarkable people, on 
 the authority of models, sculptures, and paintings, still existing. 
 The doors were frequently stained so as to imitate foreign 
 and rare woods. They were either of one or two valves, turn¬ 
 ing on pieces of metal, and were secured within by a bar or by 
 bolts. Some of these bronze pins have been discovered in the 
 tombs of Thebes ; they were fastened to the wood with nails of 
 the same metal, the round heads of which served also as orna¬ 
 ments. In the stone lintels and floors behind the thresholds 
 of the tombs and temples are still frequently to be seen the 
 holes in which the pivot-pins turned, as well as those of the 
 
ancient locks : gkecian, koman, Egyptian. 13 
 
 o is and bars, and the recess for receiving the opened valves. 
 The folding-doors had bolts in the centre, sometimes above as 
 
 well as below; a bar was placed across from one wall to the 
 other. 
 
 In many of the ancient Egyptian doors there were wooden 
 ocks fixed so as to fasten across the centre at the junction 
 where the two folds of the door met. It is difficult, by mere 
 inspection of the bas-reliefs and paintings, to decide whether 
 t lese locks were opened by a key, or were merely drawn back¬ 
 wards and forwards like a bolt; but if they were really locks 
 it is probable that they were on the same principle as the Egyp¬ 
 tian lock still in use. For greater security, these modern locks 
 are occasionally sealed with a mass of clay; and there is sa¬ 
 tisfactory evidence that the same custom was frequently ob¬ 
 served among the ancient inhabitants of that country. Sir 
 J. G. Wilkinson gives a representation of an iron key, now in 
 his possession, which he procured among the tombs at Thebes, 
 and which looks very much like a modern burglar’s picklock. 
 In relation to keys generally, and after mentioning the use of 
 bronze for their manufacture, he says : “ 'At a later period 
 when iron came into general use, keys were made of that 
 metal, and consisted of a straight shank about five inches in 
 length, and a bar at right angles with it, on which were three 
 or more projecting teeth. The ring at the upper extremity 
 was intended for the same purpose as that of our modern keys • 
 but we are ignorant of the exact time when they were brought 
 mto use; and the first invention of locks distinct from both 
 is equally uncertain; nor do I know of any positive mention 
 ot a key, which, like our own, could be taken out of the lock 
 previous to the year 1336 before our era; and this is stated 
 to have been used to fasten the door of the summer parlour of 
 Eglon, the king of Moab. The description here adverted to 
 is that contained in Judges iii. 23-25 : ‘ Ehud went forth 
 through the porch, and shut the doors of the parlour upon 
 im, and locked them .... his servants .... took a key 
 and opened them.’ ” J1 
 
14 
 
 ON LOCKS. 
 
 The curious and ingenious wooden lock of ancient Egypt 
 is still in use in Egypt and Turkey. In Eton’s Survey of 
 the Turkish Empire, published towards the close of the last 
 century, the locks then and there in use are thus described: 
 “ Nothing can be more clumsy than the door-locks in Tur¬ 
 key ; but their mechanism to prevent picking is admirable. 
 It is a curious thing to see wooden locks upon iron doors, 
 particularly in Asia, and on their caravanserais and other 
 great buildings, as well as upon house-doors. The key 
 goes into the back part of the bolt, and is composed of a 
 square stick with five or six iron or wooden pins, about half 
 an inch long, towards the end of it, placed at irregular dis¬ 
 tances, and answering to holes in the upper part of the bolt, 
 which is pierced with a square hole to receive the key. The 
 key being put in as far as it will go, is then lifted up; and 
 the pins, entering the corresponding holes, raise other pins 
 which had dropped into these holes from the part of the lock 
 immediately above, and which have heads to prevent them 
 falling lower than is necessary. The bolt, being thus freed 
 from the upper pins, is drama back by means of the key ; the 
 key is then lowered, and may be drawn out of the bolt. To 
 lock it again, the bplt is only pushed in, and the upper pins 
 fall into the holes in the bolt by their own weight.” Mr. 
 Eton, probably seeing how well the tumbler-principle is here 
 understood, says : “ This idea might be improved on ; but 
 the Turks never think of improving.” The locks on the 
 doors of modern houses in Cairo seem to be of this long-esta¬ 
 blished form, except where iron locks have been imported 
 from EiU’ope. 
 
 A letter was inserted in the Journal of Design for July 
 1850 from Mr. W. C. Trevelyan; in which, after adverting to 
 the Egyptian lock, he says : “ It is remarkable that the locks 
 which have been in use in the Faroe Islands, probably for 
 centuries, are identical in their construction with the Egyp¬ 
 tian. They are, lock and key, in all their parts made of 
 wood; of which material, if I mistake not, they have also 
 
15 
 
 ANCIENT LOCKS: GRECIAN, ROMAN, EGYPTIAN. 
 
 been found in Egyptian catacombs ; and so identical with the 
 Earoese in structure and appearance, that it would not be 
 easy to distinguish one from the other.” 
 
 fi S- 3> fig. 4. 
 
 . The construction of this remarkable Egyptian or pin-lock 
 will be understood from the accompanying engravings. The 
 quadrangular portion, a a fig. 1, is the case of the lock, screwed 
 or otherwise fastened to the door, having a wooden bolt, b b 
 passing horizontally through a cavity in it. In the part of the 
 case above the bolt are several small cells containing headed 
 pins, arranged in any desired form; and in the top of the bolt 
 itself are an equal number of holes similarly arranged. The 
 effect of this arrangement is such that, when brought into the 
 right positions, the lower ends of the headed pins drop into the 
 corresponding holes in the bolt, thereby fastening the bolt in 
 the lock-case. A large hollow, or cavity, is made at the ex¬ 
 posed end of the bolt, the cavity extending as far as and be¬ 
 yond the holes occupied by the pins. The key consists of a 
 piece of wood (shewn in two positions, figs. 3 and 4,) having 
 pins arranged like those in the lock, and projecting upwards 
 just to a sufficient distance to reach the upper surface of the 
 bolt. This being the arrangement, whenever the key is in¬ 
 troduced and pressed upwards, its pins exactly fill the holes 
 in the bolt ’ and b y so doin g dislodge those which had fallen 
 
16 
 
 ON LOCKS. 
 
 from the Tipper part of the case. The bolt may, under these 
 circumstances, be withdrawn (as shewn in fig. 2), leaving the 
 headed pins elevated in their-cells, instead of occupying the 
 position shewn by the dotted lines in fig. 1. The cavity in 
 the bolt must of course be high enough to receive the thick¬ 
 ness of the key, and also the length of the pins protruding 
 from the key. 
 
 This primitive lock comprises many of the best features of 
 the tumbler or lever-locks of later days, as will be seen in a 
 future chapter. There will also be opportunities of shewing 
 how the pin-action has been applied in other ways in some of 
 the modern locks. 
 
 CHAPTER HI. 
 
 LOCK CLASSIFICATION. THE PUZZLE-LOCK AND THE DIAL-LOCK. 
 
 In approaching the subject of modern locks it becomes necessary 
 to decide upon some method of treating the widely-scattered 
 and diverse materials which are presented to our notice. One 
 plan would be to trace the subject chronologically, by describ¬ 
 ing, in the order of their invention, the most important locks 
 which have been presented to public notice. But this would be 
 attended with some disadvantages: the peculiar characters of the 
 several locks would not be brought out with sufficient distinct¬ 
 ness ; and the result, so far as the reader is concerned, would 
 rather tend to confusion than to a clear appreciation of the 
 subject. There are more advantages belonging to a classifica¬ 
 tion of locks under certain headings, according to some marked 
 peculiarities in their modes of action. This is a convenient 
 plan, but it is not an easy one to put in execution ; for in¬ 
 ventors have not sought to place their locks in any particular 
 class, but rather to call attention to their merits. Moreover, 
 
LOCK CLASSIFICATION. THE PUZZLE-LOCK. 17 
 
 many locks embody two or three distinct principles so equally, 
 that it will often be difficult to decide in which class to place 
 them. This, nevertheless, may be done with an approach 
 to correctness. It is necessary first, however, to explain cer¬ 
 tain technical terms by which locks are distinguished one from 
 another. 
 
 Locks, in truth, admit of an immense variety, which how¬ 
 ever important to be known to locksmiths, carpenters, and 
 others employed on them, need only be glanced at very cur¬ 
 sorily by the general reader. Some locks are named according 
 to the purposes to which they are to be applied; others 
 according to their shape, or the principles of their construc¬ 
 tion. In the first place, there is the distinction between in-door 
 and out-door locks. Of in-door locks, one principal kind is the 
 draw-back lock, for street-doors, in which the bolt is capable of 
 maintaining any one of three positions : it may be locked by 
 the key, or left half-way out by the pressure of a spring, or be 
 rawn back by a handle. In the first position, it can only be 
 withdrawn by the key; in the second, it closes the door, but 
 can easily be withdrawn by the handle ; and in the third, it 
 leaves the door unfastened. If these locks are made of iron 
 and carefully finished, they are further called iron-rim; but 
 if made of wood, suitable for back-doors and inferior pur¬ 
 poses, they are spring-stock. For the doors of rooms, there 
 are the iron-nm, the brass-case, and the mortise lock; the second 
 supplants the first, and the third the second, as we advance 
 m the elegance of the door-fittings. Other designations for 
 room-locks depend on the number of the bolts : thus, if there 
 be only one bolt, it is a dead lock or closet lock; if there be a 
 second bolt, urged by a spring and drawn back by a handle 
 it is a two-bolt lock; and if there be also a third, a private 
 bolt acting only on one side of the door, it is a three-bolt lock. 
 Again, according to the kind of handle employed, it may be a 
 kmb lock or a ring lock. According to which edge of the door 
 it is to be fixed, it becomes a right-hand or a left-hand lock, 
 t e wards of the lock are of somewhat superior quality, and 
 
18 
 
 ON LOCKS. 
 
 bend round nearly to a circle, the lock is one-ward round, two- 
 ward round, and so forth. If the lock has no wards at all, it 
 is plain; if the wards are of common character, they are often 
 called wheels , and then the lock becomes one-wheel, two-wheel, 
 &c. Sometimes the lock is named from certain fancied resem¬ 
 blances in the shape of the ward, as the 'L-ivard, T-ward, or 
 Z -ward. If the wards are cast in brass, instead of being made 
 of slips of iron or copper, the lock is termed solid ward. 
 
 Of the numerous but smaller varieties known by the col¬ 
 lective name of cabinet locks, there are the cupboard, the book¬ 
 case, the desk, the portable desk, the table, the drawer, the box, 
 the caddy, the chest, the carpet-bag, and many other locks. All 
 these locks are further called straight, when the plate is to be 
 screwed flat against the wood-work ; cut, when the wood is to 
 be so cut away as to let in the lock flush with the surface ; 
 and mortise, when a cavity is excavated in the edge of the door 
 for the reception of the lock. 
 
 Out-door locks are usually wooden stock locks, for stables, 
 gates, &c.; comprising many varieties of Banbury, bastard, fine, 
 &c. There are D locks and P locks, for gates, designated from 
 their shapes ; and there are the numerous kinds of padlocks. 
 
 The above terms are employed chiefly between the makers 
 of the locks and the persons who fix them in their places ; but 
 there are other terms and names, more familiarly known, which 
 will come under notice in future pages. 
 
 It is scarcely worth while to descant upon the “ middle age” 
 of lock-making—-to impart to the subject so much of dignity 
 as to be susceptible of regular historical treatment. True, we 
 know that wards were employed before tumblers (unless, in¬ 
 deed, the pins of the Egyptian lock be considered as tumblers 
 —a character to which they present considerable claim), and 
 that wards may be taken as the representative of the medi¬ 
 eval period of lock-making ; but it may be more profitable 
 to proceed in our notice of the different kinds of locks in 
 an order which will in itself partake somewhat of the his¬ 
 torical character. 
 
19 
 
 LOCK CLASSIFICATION. THE PUZZLE-LOCK. 
 
 Apart from all the warded and tumbler locks are the very 
 curious puzzle or letter-locks; a construction which we propose 
 to dismiss out of hand in the present chapter, before treating 
 of those which have more commercial importance. 
 
 The puzzle-lock is generally in the form of a padlock, 
 which is opened and closed without the use of a key, and 
 which has certain difficulties thrown in the way of its being 
 opened by any one who is not in the secret of the person who 
 closed it. . It is, in fact, one of the locks in which the doctrine 
 of permutation is made to contribute to the means of security. 
 The key to open it is a mnemonic or mental one, instead of one 
 of steel or iron. Two centuries ago, the puzzle-lock attracted 
 far more attention than any other. It has always certain 
 movable parts, the movement of which constitutes the enigma. 
 Some of these very curious and out-of-the-way locks are so 
 formed as to receive the name of dial-locks ; but the chief 
 among them are ring-locks —a name the meaning of which 
 will be presently understood. 
 
 The puzzle or letter-lock of the ring kind, then, consists 
 essentially of a spindle ; a barrel, encompassing the spindle ; 
 two end-pieces, to keep the spindle and barrel in their places ; 
 and the shackle, hinged to one of these end-pieces. To un¬ 
 fasten the lock, one of the end-pieces must be drawn out a 
 little, to allow the shackle or horse-shoe to be turned on its 
 hinge ; and the question arises, therefore, how this end-piece 
 is to be acted upon. This is effected in a very ingenious way: 
 there are four studs or projections in a row on the spindle, 
 and as the spindle fits pretty closely in the barrel, the former 
 cannot be drawn out of the latter unless there be a groove in 
 the interior of the barrel, as a counterpart to the studs on the 
 exterior of the spindle ; four rings fit on the barrel, on the 
 interior of each of which there is a groove; and unless all 
 these four grooves coincide in direction, and even lie in the 
 same plane as the groove in the barrel, the studs will not be 
 able to pass, and the spindle cannot be drawn out. Each ring 
 may be easily made to work round the barrel by means of the 
 
20 
 
 ON LOCKS. 
 
 fingers, and to maintain any position which may be given to 
 it. There are outer rings, one over each of the rings just 
 described, with the letters of the alphabet (or a considerable 
 number of them) inscribed on each ; and these outer rings, by 
 means of notches on the inside, govern the movements of the 
 inner rings. 
 
 The action is, therefore, as follows : when the padlock is 
 to be locked, the rings are so adjusted that all the grooves 
 shall be in a right line; the spindle is thrust in, the .end-piece 
 is fixed on, and the shackle is shut down. The padlock is now 
 fastened ; but a reverse order of proceeding would as easily 
 open it again, and therefore the “ safety” or “ puzzle” prin¬ 
 ciple is brought into requisition. The outer rings are moved 
 with the finger, so as to throw the various interior grooves out 
 of a right line, and thus prevent the withdrawal of the spindle. 
 As each ring may be turned round through a large or a 
 small arc, and all turned in different degrees, the variations 
 of relative position may be almost infinite. The letters on the 
 outer rings are to assist the owner to remember the particular 
 combination which he had adopted in the act of locking ; for 
 no other combination than this will suffice to open the lock. 
 There may, for instance, be the four letters lock ina line, 
 which line is brought to coincide with two notches or marks 
 at the ends of the apparatus ; and until all the four outer 
 rings are again brought into such relative position as to place 
 the letters in a line, the lock cannot be opened. 
 
 There are many allusions to locks, apparently belonging to 
 the letter or puzzle principle, in authors who flourished two 
 or three centuries ago. Thus, in Beaumont and Fletcher’s 
 play of the Noble Gentleman , written in the early part of the 
 seventeenth century, one of the characters speaks of 
 
 “ A cap-case for your linen and your plate. 
 
 With a strange lock that opens with A'M’E'N.” 
 
 And in some verses by Carew, written about the same time, 
 there is an analogy drawn, in which one of the things com¬ 
 pared is— 
 
LOCK CLASSIFICATION. THE PUZZLE-LOCK. 
 
 21 
 
 “A lock 
 
 That goes with letters ; for till every one be known. 
 The lock s as fast as if you had found none.” 
 
 In the Memorabilia of Vanhagen von Ense, written about 
 the middle of the seventeenth century, a commendatory notice 
 is given of a letter-lock, or combination-lock, invented by M. 
 Regnier, Director of the Musee cTArtillerie at Paris. “ Regnier,” 
 we are told, « was a man of some invention, and had taken out 
 a patent for a sort of lock, which made some noise at the time. 
 Every body praised his invention, and bought his locks. These 
 consisted of broad steel rings, four, five, or eight deep, upon 
 each of which the alphabet was engraved ; these turned round 
 on a cylinder of steel, and only separated when the letters 
 forming a particular word were in a straight line with one 
 another. The word was selected from among a thousand, and 
 the choice was the secret of the purchaser. Any one not 
 knowing the word might turn the ring round for years with¬ 
 out succeeding in finding the right one. The workmanship 
 was excellent, and Regnier was prouder of this than of 
 the invention itself. The latter point might be contested. 
 
 I had a vague recollection of having seen something of the 
 sort before ; but when I ventured to say so, my suspicions 
 were treated with scorn and indignation, and I was not able 
 to prove my assertion ; but many years afterwards, when a 
 book, which as a boy I had often diligently read, fell into my 
 hands, Regnier’s lock was suddenly displayed. The book was 
 calied Silvestri a Petrasancta Symbola Heroica, printed at Am¬ 
 sterdam in 1682. There was an explanation at p. 254, at¬ 
 tached to a picture; these were the words Honorius de 
 Beilis, serulcB innexce orbibus volubilibus ac literatis circum -- 
 scripsit hoc lemma Sorte aut labored However, neither luck 
 nor labour would have done much more towards discover¬ 
 ing the secret of opening Regnier’s locks, from the variety of 
 their combinations; and their security seemed so great, that 
 
 * " de Beilis wrote this inscription, -By chance or ly labour, 
 
 round a lock composed of revolving rings graven with letters.” 
 
22 
 
 ON LOCKS. 
 
 the couriers’ despatch-boxes were generally fastened with 
 them.” 
 
 This curious extract, which was brought forward by Mr. 
 Chubb, in a paper on locks and keys (read before the Insti¬ 
 tution of Civil Engineers in 1850), seems to take away the 
 credit from one (Regnier) with whose name the letter-lock 
 has been most intimately associated. We shall presently 
 explain, however, what it was that Regnier effected towards 
 perfecting the letter-lock. In the meantime it may be in- 
 • teresting to note that the British Museum contains a copy of 
 the work mentioned by Vanhagen. At the page indicated 
 there is an engraving (a fac-simile of which is given in fig. 5) 
 containing a drawing of a veritable puzzle or letter-lock; the 
 lock consists of a cylinder or barrel, on which seven rings 
 work; each of these rings is inscribed with letters, and the 
 ends of the cylinder are grasped by a kind of shackle. 
 
 It was a natural result of the arrangement of the letter- 
 lock, as invented (conjecturally) by Cardan, that only one 
 particular word or cipher or key could be used in each lock; 
 and it was to increase the puzzle-power of the lock that Reg- 
 
10CK CLASSIFICATION. THE PUZZLE-LOCK, 23 
 
 nier doubled all the rings, making each pair concentric, and 
 enabling the user to vary the cipher at pleasure. 
 
 The principle of the letter-lock, when applied, to doors 
 requires that sort of modification which renders it what is 
 termed a dial-loch There are to such a lock one or more 
 dials, with a series of letters or figures stamped on them; 
 there is to each dial a hand or pointer connected by a spindle’ 
 ™th a wheel inside the lock; on the wheel is a notch which 
 has to be brought to a certain position before the bolt can 
 be moved. There are false notches, to add to the difficulty of 
 nding the true notch in each wheel. To adjust the notches 
 to their proper position, a nut on the back of the wheel is 
 loosened, and the pointer is set at any letter or figure chosen 
 by the user. The pointers and the dials perform the part of 
 the outer rings, the wheels that of the inner rings; and it is 
 easy to see that the same leading features prevail in the two 
 kinds of lock, however they may differ in detail. 
 
 These dial-locks have not been numerous ; they require 
 wheel and pinion work within the body of the lock, which 
 gives delicacy and complication to the mechanism. The letter 
 padlock, be its merits great or small, is strong and durable 
 not liable to get out of order; and in so far as it requires 
 no key or key-hole, it occupies rather a special position amono- 
 locks. One of our great “merchant-princes” has been a 
 letter-lock inventor, as the following will shew. 
 
 Early in 1852, Mr. William Brown, the distinguished 
 member for South Lancashire, read a paper before the Archi¬ 
 tectural and Archaeological Society of Liverpool, of much in¬ 
 terest in relation to our present subject. His object was to 
 describe a letter-lock which he had invented, and which had 
 up to that time given high satisfaction. We cannot do better 
 t an transcribe the paper, as reported in one of the Liverpool 
 Journals, with a few abridgments. 
 
 “ As your society are desirous of seeing any improvements 
 or attempts at them, I send you a stock-lock for inspection, 
 lbe idea for its construction I took from a letter-padlock. 
 
24 
 
 ON LOCKS. 
 
 I had a lock of this description made by Mr. Pooley twenty- 
 five years ago, which has been in use ever since on Brown, 
 Shipley, and Co.’s safe. 
 
 “Its advantages I conceive to be—First, it cannot be 
 picked, for there is no key-hole. Second, it cannot be blown 
 up by gunpowder, for the same reason. Third, you cannot 
 drill through the door so as to reach the lock, for you are 
 intercepted by a steel plate on which your tools will not act: 
 thus you cannot introduce gunpowder that way to force the 
 lock off. Fourth, you cannot bounce off the wheels in the in¬ 
 terior with a muffled hammer, for vulcanised India-rubber 
 springs resist this. Fifth, you cannot drill the spindles out, 
 as their heads are case-hardened. Sixth, you cannot drive 
 them in, for they are countersunk in the door about half-way 
 through. 
 
 “Now let us set the lock to the word wood (any other 
 four letters might be used). When you set the lock, make 
 a private record of them, so that you may not forget them. 
 If parties do not know your letters, nothing but violence, 
 applied by some means or other, can enable them to get into 
 your safe; for the lock will not open to any thing but its 
 talisman. Take off all the large wheels and open the lock: 
 you will see that the large wheels have a number of false 
 chambers ; if you get the spurs of the bolt into three real 
 chambers and one false, you are as fast as ever, for all four 
 must be right. 
 
 “ Having placed your key and pointer outside the door to 
 point to w on brass-plate No. 1, the small wheel inside obeys 
 the same impulse; then maintain your small wheel steadily 
 on this point, and the large wheel No. 1 will only fit on at 
 the right place, the true opening compartment being opposite 
 the spur of the bolt. It being necessary at the time you set 
 your lock that it should be open, proceed with Nos. 2 and 3 
 in the same way, your pointer standing steadily at 0. No. 4 
 is the same, the pointer being held steadily at D. You should 
 then shoot your lock two or three times, to be sure you have 
 
LOCK CLASSIFICATION. THE PUZZLE-LOCK. 25 
 
 made no mistake. Every time you shoot your bolts out, turn 
 your wheels away from the true chamber, and see when you 
 again turn your pointers to wood that your lock opens freely; 
 it is the proof that you have made no mistake, and you 
 may now venture to lock your safe. When you unlock the 
 door, and find it necessary to leave it open for a time, you 
 should shoot the bolts as if locked, and turn the wheels, so 
 that no one may find what your real letters are; and again 
 adjust them to their proper places, in order that the bolt may 
 go back and enable you to re-lock. Once having locked the 
 door and turned the wheels from your real letters, you need 
 not trouble yourself with carrying the key, but leave it in 
 any place beside the lock. 
 
 “ I believe two wheels would make a perfectly safe lock; 
 three would be quite so. I adopted four to make security 
 doubly sure, as it would be impossible in any given time to 
 work the changes. On two wheels by chance the lock might 
 open; you can, however, calculate the chances against this; 
 and also three or four, the false compartment on the outer 
 rim being taken into calculation. * * * 
 
 “ If this lock is of any value, it should be known ; if it 
 has weak points, let them be pointed out, and they may admit 
 of a remedy; for we ought not to be led to believe a lock is 
 safe which is not so.” 
 
 In relation to the “ first advantage” which Mr. Brown not 
 unreasonably supposed to be possessed by his lock—viz. that 
 “ it cannot be picked, because it has no keyhole”—we shall 
 have something to say in a future page, where certain fal¬ 
 lacies on this subject will be noticed. In the meantime we 
 may remark, that it is not a little creditable that a leading 
 Liverpool merchant should have invented a lock worthy of 
 occupying a position on his own safe for a quarter of a 
 century; for we may be quite certain that he would not have 
 allowed the lock to maintain that post of honour unless it had 
 really (so far as experience had then gone) served worthily 
 as a safeguard to his treasures. And if it were possible to 
 
 c 
 
26 
 
 ON LOCKS. 
 
 collect all the by-gone specimens of lock-oddities, we should 
 probably find among them many highly-ingenious letter-locks; 
 for supposing a man to have a mechanical turn of mind, a 
 lock is by no means an unworthy medium for displaying it; 
 the pieces of metal are so small as to be easily manageable 
 at a small work-bench in a small room. The fondness for 
 this sort of employment evinced by the unfortunate Louis XYI. 
 of France led to the common remark, “ He is a capital lock¬ 
 smith, but a very bad king.” 
 
 In an amusing article in the Observer , during the progress 
 of the “ lock controversy,” was the following paragraph relat¬ 
 ing to combination-locks of the letter or puzzle kind: “The 
 French, in their exposition of 1844, availing themselves of the 
 permutation principle, produced some marvels in the art; 
 but the principle has not been adopted in this country. The 
 Charivari had an amusing quiz upon these locks when they 
 first came out. It said the proprietor of such a lock must- 
 have an excellent memory: forget the letters, and you are 
 clearly shut out from your own house. For instance, a gentle¬ 
 man gets to his door with his family, after a country excursion, 
 at eleven o’clock at night, in the midst of a perfect deluge of 
 rain. He hunts out his alphabetical key, and thrusts it into 
 his alphabetical lock, and says azbx. The lock remains as 
 firm as ever. ‘ Plague take it!’ says the worthy citizen, as 
 the blinding rain drives in his eyes. He then recollects that 
 that was his combination for the previous day. He scratches 
 his head to facilitate the movement of his intellectual faculties, 
 and makes a random guess bclo; but he has no better suc¬ 
 cess. In addition to his being well wet, his chances of hitting 
 on the right combinations and permutations are but small, 
 seeing that the number is somewhere about three millions five 
 hundred and fifty-three thousand five hundred and seventy- 
 eight. Accordingly, when he comes to the three-hundredth 
 he loses all patience, and begins to kick and batter the door; 
 but a patrol of the National Guard passes by, and the dis¬ 
 turber of the streets is marched off to the watch-house.” 
 
WARDED LOCKS, WITH THEIR 
 
 APPENDAGES. 
 
 27 
 
 CHAPTER IV. 
 
 WARDED LOCKS, WITH THEIR VARIED APPENDAGES. 
 
 Phe more ordinary locks are of an oblong quadrangular shape. 
 
 nearly aU of them, either a bolt shoots out from the lock 
 o catch into some kind of staple or box, or a staple enters a 
 hole m the edge of the lock, and is there acted upon by the bolt 
 A common room-door lock will illustrate the first of these 
 nds, a tea-caddy lock the second. The key, as is well known, 
 enters a receptacle made for it; and the shaft of the key gene¬ 
 rally serves as a pivot or axis around which the web or flat 
 part of the key may move in a circular course. During this 
 movement the web acts directly or indirectly on the bolt, 
 riving it m or out according to the direction in which the 
 ey is turned; the key impels the bolt one way, certain 
 springs act upon it in another, and the balance between these 
 two forces determines the locking and unlocking of the bolt. 
 Wards or wheels, are contrivances for rendering the opening 
 fficul without the proper key; and it is of warded locks that 
 we shall chiefly treat in this chapter. 
 
 fig. 6. Interior of a back-spring warded lock. 
 
 The annexed cut, fig. 6, represents the interior of an ordi¬ 
 nary back-spring lock, without tumblers. Such a lock may 
 
28 
 
 ON LOCKS. 
 
 usually be known from a tumbler-lock by this simple circum¬ 
 stance, that it emits a smart snapping noise during the process 
 of locking, occasioned by the pressure of the spring when the 
 bolt is in a particular position. In the woodcut the bolt is 
 represented half out, or half shot. At a a are two notches on 
 the under side of the bolt connected by a curved part; b is the 
 back spring, which becomes compressed by the passage of the 
 curve through a limited aperture in the rim c c of the lock. 
 When the bolt is wholly withdrawn, one of the notches a rests 
 upon the rim cc; and the force with which the notch falls 
 into this position, urged by the spring b, gives rise to the 
 snapping or clicking noise. When the bolt is wholly shot, 
 the other notch rests in like manner upon the edge of the aper¬ 
 ture in the rim. 
 
 It must be obvious at a glance, that this back-spring lock 
 is objectionable on the score of security, on account of the 
 facility with which the bolt may be forced back by any pres¬ 
 sure applied to its end, a pressure which may often easily be 
 brought to bear. At the centre of the lock is seen the end of 
 the key acting on a notch in the bolt, and surrounded by 
 wards. 
 
 It is not at a first glance that the relation between the 
 clefts in a key and the wards of a lock can be duly appre¬ 
 ciated ; because the wards present themselves to view as por¬ 
 tions of circles to which nothing in the key seems to corre¬ 
 spond ; but if it be borne in mind that the key has a rotary 
 
WARDED LOCKS, WITH THEIR APPENDAGES. 
 
 29 
 
 motion within the key-hole around the pipe or barrel as an 
 axis, the circular form of the wards will be accounted for, and 
 their section wall be regarded as exhibiting the looked-for 
 relation to the wards of the key. In the annexed cut, for 
 example (fig. 7), which represents a portion of the interior of a 
 warded lock, the curved pieces of metal are the wards (two in 
 this case); and there are two clefts in the bitt of the key to 
 enable the latter to take its circular course without interruption 
 from the wards. If the clefts were other than they are, either 
 in number, position, or size, this freedom of the key’s move¬ 
 ment could not be obtained. 
 
 When once the opinion became established that a lock is 
 rendered secure by virtue of its wards, (a theory which we 
 shall have to discuss in a later page,) much ingenuity was dis¬ 
 played in varying the wards of the lock, the clefts of the key, 
 and the shape of the keyhole. Even if the two former were 
 unchanged, a change in the latter might add to the puzzle¬ 
 ment of the arrangement. For instance, in the annexed cut 
 
 fig. 8. End sections of keys. 
 
 (fig. 8), all the six keys represented may have clefts or cuts 
 exactly alike, all alike adapted to the wards of one particular 
 lock; yet the differences in the thickness of the web are such, 
 that if the keyholes were shaped in conformity therewith, each 
 keyhole would be entered by one of these keys; b and c dif¬ 
 fering from a in the relative thickness at different points, and 
 d, e, and f having certain curvatures and cavities not to be 
 found in the other three. 
 
 But without waiting for the detailed examination of the re¬ 
 lative security and insecurity of locks, we may at once shew 
 how simple is the principle which renders the warded system 
 
30 
 
 ON LOCKS. 
 
 fallacious. In fig. 9 we shall be able to illustrate this. 
 Numbers 1,2, and 3, all appear very different keys, and it is 
 
 fig. 9. Examples to shew the action of “ master,” or “ skeleton keys.” 
 
 quite true that neither one would open a lock adapted for 
 either of the other two; and yet the very simple arrangement 
 No. 4 would open all three. This No. 4 is called a skeleton- 
 key ; and the relation which it bears to the others may be ex¬ 
 pressed in the form of a proposition thus : at any point where 
 there is solid metal in all the keys, there must (or may) be 
 solid metal in the corresponding part of the skeleton-key ; but 
 at any point where there is a vacancy or cavity in any of the 
 keys, there must be a cavity in the corresponding part of the 
 skeleton-key. If Nos. 1, 2, 3, 4, be examined, this proposi¬ 
 tion will be found to be borne out; there is so much cavity 
 in No. 4 that it avoids the wards in all the three locks, nothing 
 being required but the tongue of metal to move *the bolt. 
 Sometimes, to add to the safety, wards are attached to the 
 front as well as the back plate of the lock; and then there may 
 be a double series of notches required in the key, such as in 
 No. 5; but if this be compared with Nos. 9, 10, 11, it will be 
 found that although no one of the four would open a lock 
 
WARDED LOCKS, WITH THEIR APPENDAGES. 
 
 31 
 
 adapted for either of the other three, jet the skeleton-kej No. 
 12 would master them all, having cavities wherever any of the 
 others have cavities. This is the theory of the master-key , by 
 which one key may be made to command many locks. Nos. 
 6 and 7 have complicated wards ; but the key is so much cut 
 up as to be weakened more than is desirable. No. 8 enables 
 us to point out the difference between two distinct classes of 
 keys. Keys with pipes or barrels fitting on a pin or pipe- 
 shaft can only open a lock on one side of the door or box; 
 but a key with a solid stem, as No. 8, has the clefts' so cut as 
 to open the lock from either side, as in a street-door lock: it is, 
 in fact, two warded keys fixed end to end, only half of which 
 is employed at one time in opening the lock. 
 
 fig. 10. Wards of an old French lock. 
 
 Some of the warded locks of the last century are curious. 
 While the idea prevailed that a complicated ward gave secu¬ 
 rity, there was room for the exercise of ingenuity in varying 
 the shape of the wards. Fig. 10 is copied from the great 
 French work. It represents the cuts in the key, and also 
 (seen perspectively) the complicated forms of the pieces of 
 metal which constitute the wards corresponding with those 
 cuts. The aperture in the key at 16 fits upon the metal 
 surrounding the keyhole at 18; and the M-shaped cuts at 
 17 fit in like manner upon the similarly-shaped metal pieces 
 at 19. 
 
 Another example of a similar kind is shewn in fig. 11 ? 
 where an anchor appears to have been the favourite form. The 
 
32 
 
 ON LOCKS. 
 
 anchor cuts in the key are shewn at 26; while in the wards 
 
 fig. 11. Wards of an old French lock. 
 
 the bottom of the anchor is near the keyhole at 28, and the top 
 at 29. 
 
 fig. 12. Wards of an old French lock. 
 
 ft 
 
 A similar illustration occurs in fig. 12, where the star-like 
 cuts at 34 on the key correspond with the star-like wards 
 at 33. 
 
 From the fifteenth to the eighteenth centuries locks were 
 made in France, on which a vast amount of care and ex¬ 
 pense was bestowed. They were, in an especial degree, 
 decorative appendages as well as fastenings. They were of 
 three kinds : room-locks, buffet-locks, and chest-locks; they 
 were fixed on the outside of the door or lid, so as to be fully 
 visible. The key had a multitude of perforations which bore 
 no particular relation to the wards of the lock, but which were 
 regarded as tests of the workman’s skill. The honorary dis¬ 
 tinctions awarded to apprentices and aspirants in the art de¬ 
 pended very much on the number and fine execution of these 
 perforated keys. The locks, considered as fastenings, had 
 slender merit; although usually throwing four bolts, they were 
 not very secure. Fig. 13 represents the exterior of a lock 
 made about the year 1730, by Bridou, a celebrated Parisian 
 locksmith. It was a lock belonging to a coffer or strong 
 
WARDED LOCKS, WITH THEIR APPENDAGES. 
 
 33 
 
 chest; all the works being sunk below the level of a carved 
 architectural moulding or ornament. There is a secret open¬ 
 ing near the part c, forming a portion of the ornamental de- 
 
 fig. 13. Exterior of an old secret lock. key-hole. 
 
 sign; it allows a bolt, shewn at d, fig. 14, acted on by the 
 spring e, to be touched, by which a doorway opens upon the 
 hinges at be. a a are a sort of pilasters, which aid in forming 
 a hold for the bolts. The little ornament at c is drawn down 
 by the hand, opening the secret door and revealing the kej'- 
 hole g. s s, o o, z z, are ornaments fastened on at b c d, fig. 14, 
 by nuts and screws, intended to display the skill of the work- 
 
34 
 
 ON LOCKS. 
 
 man. The lock itself, access to the keyhole of which is ob¬ 
 tained within the secret door, has nothing very remarkable 
 about it. 
 
 Mr. Chubb, in his paper read before the Institute of Civil 
 Engineers, illustrated the insecurity of the warded lock by the 
 example of one which had actually been placed in the strong¬ 
 room of a banking house, and which is represented in the 
 
 fig. 15. Examples of true and false keys. 
 
 annexed cut (fig. 15). The wards are here shewn, surround¬ 
 ing the central key-pin ; and from the appearance of the key, 
 shewn at a , it is evident that these wards must have been 
 rather complex. But the uselessness of the wards was proved 
 by the result. A burglar employed an instrument, shaped like 
 that at b, having on one of its faces, or sides, a layer of wax 
 and yellow soap; this instrument, being introduced through 
 the keyhole and turned a little way round, brought the soft 
 composition in contact with the ends of the wards, and these 
 ends thus left their impress on the composition. A false key 
 was then made, as at c, which, however clumsy it may appear, 
 has a cavity, or vacuity, where there is a cavity in the true 
 key ; and by such a surreptitious instrument was the lock 
 opened. Even so rude an instrument as d, by passing round 
 the wards, might open such a lock. 
 
 We are somewhat anticipating the full consideration of this 
 
WARDED LOCKS, WITH THEIR APPENDAGES. 35 
 
 subject; but it is desirable at once to explain how and why 
 an improvement on the warded lock was sought for. 
 
 In connexion with the fanciful eighteenth-century locks, 
 lately adverted to, we may remark, that no less a man than 
 Louis XYI. was an amateur workman in this department of 
 mechanical art—or at least in smith’s work, which in France 
 is generally considered to include lock-making. Sir Archi¬ 
 bald Alison says, in his History of Europe :—< £ He had an 
 extraordinary fondness for athletic occupation and mechani¬ 
 cal labour; insomuch that he frequently worked several hours 
 a-day with a blacksmith of the name of Gamin, who taught 
 him the art of wielding the hammer and managing the forge. 
 He took the greatest interest in this occupation, and loaded 
 his preceptor in the art with kindness ; who returned it by 
 betraying to the Convention a secret iron recess which they 
 had together worked out in the walls of the cabinet in the 
 Tuileries, wherein to deposit his secret papers during the 
 storms of the Kevolution.” There are not wanting indica¬ 
 tions that the unfortunate monarch wrought upon locks, as 
 well as upon safes and strong-rooms. 
 
 Besides wards, there have been numerous other contriv¬ 
 ances for adding to the security of locks—including screws, 
 escutcheons, spiral springs, wheel-and-pinion work, alarums, 
 and multiple bolts. As these are not of sufficient importance 
 to be treated in separate chapters, we shall here give just 
 so much notice of them as will illustrate their general charac¬ 
 ter. Some of them are found combined with the “ tumbler” 
 principle, presently to be described; but ah of them, it is now 
 well known, were employed in various.ways when the tumbler 
 lock was but little understood, and when the warded lock was 
 held in esteem. 
 
 The Marquis of Worcester, whose curious Century of In¬ 
 ventions, written nearly two hundred years ago, contains so 
 many suggestions which ingenuity has since developed into 
 practical completeness, gives four of his inventions in the 
 following words :— 
 
3G 
 
 ON LOCKS. 
 
 69. “ A way how a little triangle screwed key, not weigh¬ 
 ing a shilling, shall be capable and strong enough to bolt and 
 unbolt, round about a great chest, an hundred bolts, through 
 fifty staples, two in each, with a direct contrary motion; and 
 as many more from both sides and ends ; and, at the self-same 
 time, shall fasten it to the place beyond a man’s natural 
 strength to take it away; and in one and the same turn both 
 locketh and openeth it. 
 
 70. “A key with a rose-turning pipe and two roses pierced 
 through endwise the bit thereof, with several handsomely con¬ 
 trived wards, which may likewise do the same effects. 
 
 71. “A key, perfectly square, with a screw turning within 
 it, and more conceited than any of the rest, and no heavier 
 than the triangle screwed key, and doth the same effects. 
 
 72. “ An escutcheon, to be placed before any of these locks, 
 with these properties: First, the owner, though a woman, may 
 ■with her delicate hand vary the ways of causing to open the 
 lock ten millions of times beyond the knowledge of the smith 
 that made it, or of me that invented it. Second, if a stranger 
 open it, it setteth an alarum a-going, which the stranger can¬ 
 not stop from running out; and besides, though none shall be 
 within hearing, yet it catcheth his hand as a trap doth a fox; 
 and though far from maiming him, yet it leaveth such a mark 
 behind it as will discover him if suspected; the escutcheon or 
 lock plainly shewing what money he hath taken out of the 
 box to a farthing, and how many times opened since the owner 
 had been at it.” 
 
 Mr, Partington, in his edition of the marquis’s singular 
 work, makes a few comments on these lock- and-key contriv¬ 
 ances. He says that the lock is evidently intended to operate 
 on the principle of applying a screw for the purpose of moving 
 the bolt, instead of using a key as a lever for this purpose. 
 That such a plan might be applied to locks generally, he 
 observes, there can be no doubt; and by a similar contrivance 
 the large keys at present in use for outer doors, iron chests, 
 Oic. might be advantageously reduced by this means. By 
 
WARDED LOCKS, WITH THEIR APPENDAGES. 
 
 37 
 
 employing the escutcheon mentioned by the marquis, much 
 additional security would be obtained. It must be confessed, 
 however, that many of the marquis’s statements are difficult 
 to credit. 
 
 The escutcheon has been a favourite resource with lock- 
 makers. Mr. Mordan’s escutcheon, for instance, introduced 
 before the Society of Arts in 1830, is a contrivance to be 
 placed temporarily over the keyhole of a door, to prevent 
 the picking of the lock during the owner’s absence. The 
 escutcheon, or “ protector,” has a short pipe which, after the 
 door has been locked, is thrust into the keyhole ; attached to 
 the pipe is a small lock, on Bramah’s or any other convenient 
 principle, so contrived that, on turning its key, two lancet- 
 shaped pieces fly out laterally and bury themselves in the 
 wood. The escutcheon cannot be removed until the small 
 key has reacted upon the small lock; and until this removal 
 has taken place, the large key cannot reach the keyhole. 
 
 A curious application of the escutcheon principle attracted 
 some attention among locksmiths about seventy years ago. 
 One of the first premiums awarded by the Society of Arts, 
 after the commencement of their “ Transactions,” was to Mr. 
 Marshall, for a “ secret escutcheon,” in 1784. In his descrip¬ 
 tion of his new invention, he adverts to the marquis of Wor¬ 
 cester’s wonderful escutcheon, and to the many attempts which 
 have since been made to produce an apparatus which should 
 realise the marquis’s description. He supposes that the letter 
 padlock originated as one among many varieties of these imi¬ 
 tative inventions ; but this may be doubted. Mr. Marshall’s 
 contrivance, however, was in effect an endeavour to improve 
 upon the letter-lock. He considered it an objection that, in 
 ordinary locks of this kind, the letter-rings admit of no vari¬ 
 ation of place; and he sought to remedy this defect. It is 
 not so much a new lock, as an escutcheon for a lock, which 
 he produced. There is a studded bar passing through a bar¬ 
 rel ; there are five rings which work concentrically on this 
 barrel; there are letters on the outer surfaces of the rings, 
 
38 
 
 OX LOCKS. 
 
 and notches on the inner surface; but when, by the usual 
 puzzle-action of the rings, the notches in them have been 
 brought into a right line with the studs of the bar, the result 
 is, not that the hasp of a padlock is raised, but that the 
 escutcheon is removed from the keyhole of an ordinary lock. 
 Mr. Marshall’s contrivance, therefore, is not so much a ring pad¬ 
 lock, as a puzzle-ring security for the escutcheon of a fixed lock. 
 
 Some locks work by a screw and a spiral spring, instead 
 of an ordinary key. Mr. W. Russell received a silver medal 
 from the Society of Arts, about thirty years ago, for a new 
 mode of locking the cocks of liquor-casks. Under ordinary 
 circumstances, as is well known, the cock of a barrel or cask 
 is in no way secure from the action of any one who can 
 approach near enough to touch it; and different methods have 
 been adopted of obtaining this security or secrecy. One plan 
 is to employ a perforated cap, soft-soldered to the barrel of the 
 cock, immediately over the grooved plug, the top of which plug 
 is formed to the shape of the perforation, and a socket-key of 
 the same form is introduced to turn the plug or open the lock. 
 Another plan is to employ an iron saddle or staple, passing 
 over the plug and below the bottom of the cock, through 
 which a bolt is put, and a pendent padlock attached. The 
 first method is very inefficient; the second is much superior, 
 and has been largely adopted for locking the cocks of coppers, 
 stills, vats, and other large vessels. But Mr. Russell thought 
 some further improvement wanted. He caused a hole to be 
 bored through the barrel, and to some depth into the plug 
 when the latter is in the position for closing the cock. A 
 stud works into this hole in such a way, that when the stud 
 is driven home, the plug cannot be tinned or the lock opened. 
 The stud is attached at its other end to a spiral spring con¬ 
 nected with a screw; a key is employed, the hollow pipe of 
 which has an internal screw; and when this key is inserted 
 in the cock-barrel and turned twice round, it draws back the 
 stud, and allows the plug to. be turned round in the proper 
 way for opening the cock. 
 
WARDED LOCKS, WITH THEIR APPENDAGES. 
 
 39 
 
 It is not often that wheel-ancl-pinion work is introduced 
 into iocks; the delicacy, the costliness, the weakness, and the 
 tendency to get out of order, would all militate against the 
 fiequent adoption of such a course. It is, however, adopted 
 occasionally. Mr. Friend’s secret-lock, introduced to the no¬ 
 tice of the Society of Arts in 1825, had a train of wheels 
 which acted upon the bolt, driving it out whenever the circular 
 arcs of three wheels moved against it, but allowing a spring 
 t° force it back again whenever a deep cleft in each of the 
 wheels locked into a stud on the bolt. There w T ere certain 
 numbers on a guide-plate, and a power of combining these 
 numbers in great variety; and a provision that the bolt could 
 be unlocked only by the same combination of numbers which 
 had locked it. The guide-plate was a separate piece of appa¬ 
 ratus, earned in the pocket of the user as a companion to 
 the key. The key was of no use without the guide-plate, 
 nor the guide-plate without the key. The user ‘ set’ the 
 numbers on the guide-plate, then applied it to the face of the 
 logk, then introduced the key into the key-hole, and turned 
 the key partially round; the bolt was now shot, and the guide- 
 plate removed. If the key were used without the guide-plate, 
 the bolt might be locked, but it was always unlocked again 
 by the time the key had made a complete circuit. There was 
 considerable ingenuity in the idea of this lock; but we believe 
 it never went further than a model. Indeed many of the locks 
 elaborately described in books have never had an existence as 
 acting working locks. 
 
 A a ery ingenious principle has been occasionally intro¬ 
 duced, in which clock-work regulates the interval of time 
 which must elapse before a lock can be opened, even with its 
 proper key. The object is, to ensure the safety of the lock 
 I during a journey, or until a particular person be present, or 
 until the locked article is conveyed to a particular room. 
 
 A patent was taken out in 1831 for a lock on this principle 
 by Mr. Kutherford, a bank agent at Jedburgh. Against the 
 end of the bolt of the lock is placed a circular stop-plate, so ' 
 
 
40 
 
 ON LOCKS. 
 
 adjusted that the bolt cannot be withdrawn until a particular 
 notch in the rim of the circular plate is opposite the end of 
 the bolt. The plate is put in rotation by clock-work. As 
 the notch can be set at pleasure to any required distance from 
 the end of the bolt, the lock may be secured against being 
 opened, either by its own or any other key, until any as¬ 
 signed number of minutes or hours after it has been locked; 
 for the plate may be made to revolve either slowly or quickly, 
 by varying the number of wheels in the clockwork. When 
 the lock is used for boxes or portable packages, the clockwork 
 must be moved and regulated by a spring; but when it is 
 applied to closets or safes, a descending weight and a pendulum 
 may be employed. It is manifest that this system is sus¬ 
 ceptible of being greatly varied in its mode of application; 
 and it has many points of interest about it. That a man 
 cannot open his own lock with his own proper key, until the 
 lock gives permission by assuming a particular state or con¬ 
 dition, certainly strikes one as being susceptible of many useful 
 applications, where time is an element taken into the account. 
 
 A curious alarum-lock was invented by Mr. Meighan, in 
 183G, in which the bell or alarum is not placed behind a 
 door, as in many alarum contrivances, but within the lock 
 itself. Two or more studs are placed on the bolt, which press 
 against the lower end of a small tumbler; the movement of 
 the tumbler elevates a hammer; but as soon as the point of 
 the tumbler becomes released from the stud, a spring presses 
 the hammer down forcibly, and causes it to strike against a 
 small bell placed near it. This sounding of the bell will be 
 repeated, during the shutting of the bolt, as many times as 
 there are studs to act upon the point of the tumbler. 
 
 Much of the ingenuity which has been displayed in locks 
 depends on the employment of multiple bolts, there being all 
 the additional strength which results from the use of two or 
 more bolts instead of simply one. Ordinary doors seldom 
 afford us examples of these double bolts; but they may be fre¬ 
 quently seen in cabinets and desks, where two staples fixed to 
 
WARDED LOCKS, WITH THEIR APPENDAGES. 41 
 
 the lid fall into two holes in the lock, and are retained by two 
 bolts. The most remarkable and complicated varieties, how¬ 
 ever, are those in which the bolts, instead of shooting parallel 
 and nearly together, shoot in wholly different ways ; one up, 
 one down, one to the right, one to the left, and so on. It is 
 on safes, strong boxes, and the doors of strong rooms con- 
 j tabling valuable treasures, that such locks are usually placed. 
 The mechanism is such that the key acts upon all the bolts 
 at once, through the intervention of levers and springs of 
 ; ! various kinds. 
 
 fig. 16. Multiple bolts of an old chest-lock. 
 
 The above woodcut represents a very curious specimen 
 of these multiple-bolt locks. It is copied from the great French 
 work; and the ponderous chest to which it is attached is, we 
 are told by Reaumur, « known at Paris by the name of the 
 strong German coffer.” He further says, “ nothing is wanting 
 m these coffers on the score of solidity. They are made 
 entirely of iron; or if of wood, they are banded both within 
 md without with iron; and can only be broken open by very 
 
42 
 
 ON LOCKS. 
 
 great violence. Their locks are almost as large as the top of 
 the coffer, and close with a great number of bolts. The one 
 which we have engraved lias twelve fastenings; they have been 
 made with twenty-four, or more.” His next remark on the 
 subject is a sensible one: “Notwithstanding the large size of 
 these locks, and all the apparatus with which they are pro¬ 
 vided, they correspond but ill with the solidity of the rest of 
 the coffer. If we have given a representation of one, it is 
 chiefly to shew how little confidence one could have in such 
 a lock, and what are its defects, in order that we may avoid 
 them.” It is not difficult, by tracing the action of the several 
 levers, to see how one movement of the key, in the centre of 
 the lid, would act upon all the bolts. In the engraving (fig. 16) 
 a,fh,c, are the four corner bolts; six others, ade, ade, are on 
 the long sides, three on each; and two, b < 7 , on the short sides. 
 Every bolt is provided with a spring, of which three or four 
 are shewn at z z z. There is no staple or box to receive 
 each bolt; but all shoot or snap beneath the raised edge E 
 running round the top of the box just within the exterior at 
 A a. The keyhole in the front of the box at D is a deception 
 or mask; the real keyhole is in the middle of the lid concealed 
 by a secret door opened by a spring. When the key has 
 moved the great central bolt, this acts upon the other bolts 
 r Q R s t, &c.; v V are studs which act upon two of the bolts; 
 yt are staples confining the great bolt; k,l,c,p,x, are small 
 levers which transmit the action to the corner bolts; q,r,s,t,n, 
 are the small levers which render a similar service to the side 
 and end bolts ; l l within the chest, and m m on the lid, are 
 contrivances for limiting the movement of the latter; ch,hc 
 are iron straps or bands by which the interior of the chest is 
 strengthened. After all, this is not so much a lock as a series 
 of spring latches. 
 
 If a lock can be picked, the picking is as effective whether 
 the lock has one bolt or twelve bolts. This fact led Mr. Duce, 
 in 1824, to construct, instead of a four-bolt lock, four distinct 
 one-bolt locks, fixed in the same frame and opened by the 
 
OX TUMBLER, OR LEVER LOCKS. 
 
 43 
 
 same key ; the bolts to be moved in succession instead of 
 simultaneously. It would require four times as long to pick 
 this as a four-bolt lock of similar action. 
 
 There have been many other varieties of the multiple bolt, 
 but we need not stop to describe them. 
 
 CHAPTER Y. 
 
 . 
 
 ON TUMBLER, OR LEVER LOCKS. 
 
 Security being the primary object in all locks, any conside¬ 
 rations as to mechanical ingenuity and graceful decoration 
 
 I give place to those which relate to safety. A spring lock 
 may be ingenious and even beautiful in its construction, but 
 an imitative key will easily open it. Hence arose the inven¬ 
 tion of wheels or wards; and as wards failed in trustworthi- 
 
 I ness, they in their turn yielded to something better. We have 
 already explained how the insecurity of mere warded locks 
 arises; and we shall have something more to say on the subject 
 in a future chapter. It is sufficient here to remark, that wards, 
 springs, screws, alarums, wheel-work, escutcheons,— all, how¬ 
 ever useful for particular purposes, are wanting in the degree 
 of surety which we require in a lock. Plence the invention of 
 . tumblers, levers , or latches , which fall into the bolt and prevent 
 it from being shot until they have been raised or released by 
 the action of the key. We have been unable to ascertain at 
 what time, or in what country, or by whom, tumbler-locks 
 were invented. The invention has been claimed by or for 
 persons subsequently to the year 1767, when the celebrated 
 French treatise (Art du Serrurier ) already referred to was 
 published ; and yet this treatise contains numerous examples 
 of simple tumbler locks of ingenious construction, as will pre¬ 
 sently be shewn. 
 
44 
 
 ON LOCKS. 
 
 One of the most elementary forms of tumbler-lock is shewn 
 in fig. 17. In this case the bolt, instead of having two notches 
 in the bottom edge, like those in the back-spring lock, fig. 6, 
 
 fig. 17. Simple tumbler lock. 
 
 has two square notches or slots in the upper edge; and as the 
 key acts upon the bolt, these notches must of course share in 
 whatever movements the bolt is subjected to. Behind the bolt 
 is a kind of latch or tumbler (the lower part of which is shewn 
 by dotted lines), with a stamp or projecting piece of metal at a; 
 the tumbler moves freely on a pivot at the other end, and is 
 made to rise through a small arc whenever the key acts upon 
 the bolt. When the bolt is wholly shot, the stamp falls into 
 one notch and prevents the motion of the bolt; when wholly un¬ 
 shot or withdrawn, the stump falls into the other notch, and 
 equally prevents the motion of the bolt. It is not, therefore, 
 until the key, by elevating the tumbler, has raised the stump 
 out of the notch, that the bolt has freedom of movement. If 
 the shape of the key does not enable its web to effect this 
 elevation to a sufficient degree, the bolt remains immovable; 
 and to this extent a certain additional security is obtained by 
 making the shape of the key significant as well as the wards. 
 
 The tumbler-principle, as we have said, is difficult to trace 
 to its origin on account of the various aspects which it pre¬ 
 sents; but the great French treatise proves that the locksmiths' 
 of France were familiar with tumbler-locks a century ago. 
 The plates of that work represent the details of numerous 
 locks, on the upper edge of the bolts of which were notches 
 called encoches, as at o k fig. 18; into these notches sank a 
 
ON TUMBLES, OR LEVER LOCKS. 
 
 45 
 
 small iron stud or stump called the arret du pene, or bolt-stop, 
 shewn in fig. 19, attached to the upper portion of the gachette 
 or tumbler, which, for the sake of economy of metal, is made 
 in the form of a triangular spring in front of the bolt hi; 
 and not until the key, by 
 its circular action, had raised 
 this stud out of one or 
 other of the notches, could 
 the bolt move to the right 
 
 fig. 18. 
 
 or left. The stud was generally fixed to a spring which 
 forced it down again into the notch as soon as the action 
 of the key had ceased. Sometimes, however, the stud was 
 fixed to the bolt, and the notches were in a separate tumbler 
 or gachette (see E e, fig. 21); and in other instances, again, 
 the stump was fixed to the case of the lock and caught 
 into notches in the bolt. It will be seen, when we come to 
 treat of tumbler-locks of later date, that there was much 
 in these early locks to point out the way. Fig. 19, copied 
 from the French work, represents a lock of the box or casket 
 kind. Two staples, fixed into the cover, fall into two cavities 
 or receptacles at cd; and a short bolt in each receptacle 
 crtches into each staple, one near g and one near h. The 
 small bolt q is attached to the upper extremity of the lever 
 qrs, fig. 19, and shewn separately in fig. 20; and by the 
 pressure of a spring a (fig. 19) upon this lever, the bolt 
 
46 
 
 ON LOCKS. 
 
 q is kept locked in the staple. The vertical por¬ 
 tion of this spring presses at its lower end on 
 another spring p (fig. 19) of singular curvature; 
 and attached to the horizontal part of this second 
 spring is the stud, which falls into a notch in the 
 top of the bolt. The action of these parts, then, 
 is as follows: when the key is placed upon the 
 key-pin at z, and turned round in the direction in 
 which the hands of a watch move, the bitt presses 
 against the tail s of the lever, moves it upon its 
 centre z, fig. 19, v, fig. 20, to the left, and con¬ 
 sequently moves the upper part q to the right, 
 drawing it out of the receptacle and liberating the 
 staple within c. Thus it will be seen that the lever 
 qrs, held in one position by the spring a, forms in itself a 
 simple kind of spring catch-lock, and was, in fact, formerly used 
 as such, without any other appendages except the staple in 
 the lever, into which the catch q fitted on shutting down the 
 lid. So also we may regard the other portion, fig. 18, or Jc ip h 
 (fig. 19), as forming a separate lock; for the key after having 
 passed s comes in contact with the triangular-spring, which it 
 raises thereby, lifting the stud out of the bolt, and exerting 
 pressure against the barbs of the bolt n. Fig. 18 shoots the 
 bolt k, and also the short bolt l, which passes through the 
 staple in the cavity eZ, fig. 19. 
 
 The lock represented in the four following figures is also 
 
 fig. 20. 
 
 fig. 21. Details of an old French lock. 
 
 from M. de Reaumur’s chapter on locks in the work referred 
 to. In this lock the tumbler-principle is carried out in a very 
 
ON TUMBLER, OR LEVER LOCKS. 
 
 47 
 
 elaborate manner, for not only is the stump or stud h (fig. 23) 
 attached to a very strong spring (best shewn at h, fig. 22), 
 
 fig. 22. Another view of the same. 
 
 which holds it with considerable force in one of the three 
 notches of the principal bolt rs (fig. 24); but there is also a 
 second set of notches ee in the gdchette Go (fig. 21), and a pin 
 
 attached to one of the plates of the lock fits into one of these 
 notches thereby preventing the bolt from being moved until 
 the gachette is lowered by the revolution of the key; so that 
 
48 
 
 ON LOCKS. 
 
 in attempting to pick this lock, not only must the spring H be 
 raised so as to release the stud from the notches of the great 
 bolt, but the gachette must be lowered to disengage the fixed 
 pin from the notches. There is yet a third source of security. 
 Attached to the large bolt are short projecting pins f (fig. 21), 
 against which an arm or detent, gf, of the gachette projects, thus 
 preventing the bolt from being shot back by any pressure 
 applied to its extremity s. 
 
 There are a few details relating to this remarkable lock, 
 which may as well be introduced here in order to complete 
 the description. The principal bolt can be shot twice, or be 
 double-locked; hence it is furnished with three barbs for the 
 key to act against, and with three notches for the spring-stud. 
 The lower bolt i k can be shot by the horizontal pressure of 
 the button p (figs. 22, 23), which is situated on the inner side 
 of the door to which this lock is attached, so that a person in¬ 
 side the room can secure the door against any one on the out¬ 
 side who is not furnished with the proper key, for it must be 
 remarked that the small bolt as well as the large one is acted 
 on by the key. Now supposing the small bolt to be shot or 
 locked, it is kept so by the pressure of the coiled spring Q 
 (figs. 21, 22). But this small bolt is connected with the large 
 one by means of the bent lever onm (figs. 21, 24), which 
 turns on a pin n attached to the main bolt. Now, when both 
 bolts are either fully shot or unshot, the arm o n lies flat 
 against and parallel with the main bolt; but when the large 
 bolt is unshot and the small one not moved, the arms on, nm, 
 fall into an inclined position, and the arm o N passing a little 
 below the main bolt comes within the range of the web of the 
 key, which in its revolution causes the bent lever to move upon 
 its centre N, thereby restoring on to its horizontal position, 
 and at the same time causing the arm N M to move from right 
 to left, or in the direction for unshooting the small bolt; the 
 end of this arm thus catches into a mortise v (figs. 21, 24) in 
 the small bolt, and immediately unlocks it. 
 
 But to return to the subject of tumbler-locks. About the 
 
ON TUMBLER, OR LEVER LOCKS. 
 
 49 
 
 year 1778, Mr. Barron introduced that species of double-action 
 (as it may perhaps be termed) which so greatly increases the 
 security of the simple tumbler, fig. 17. In the tumbler-locks 
 previously made, if the tumbler were raised sufficiently high, 
 the lock could be opened: there was no such possibility as rais¬ 
 ing it too high; but Mr. Barron, by his invention, patented 31st 
 October, 1778, rendered it absolutely necessary that a limit 
 should be put to the height to which the tumbler should be 
 raised, by rendering the bolt equally immovable whether the 
 tumbler were too much or too little raised. Another important 
 improvement was the introduction of two tumblers instead of 
 one. The bolt has in its middle a slot or gating notched on 
 both edges, the notches being fitted for the reception of studs 
 fixed to the tumblers. Supposing the studs or stumps of the 
 tumblers to be resting in the lower notches, they require to be 
 elevated to the general level of the gating before the bolt can 
 be moved; whereas, on the other hand, if the tumblers were 
 raised ever so little too high, the studs will enter the upper 
 notches, and prevent the shooting of the bolt. The lower 
 edge, or belly, of each tumbler is acted on by the steps of the 
 key during its circular movement; the leverage of the key 
 being so exactly adjusted as to raise the tumbler to the desired 
 height and no further. The tumblers are made unequally 
 wide, so that steps or inequalities in the bit of the key are 
 reqnisite to lift them both to the proper height. There are 
 thus two improvements introduced: there are two tumblers 
 instead of one, and each tumbler has a double instead of a 
 single action. 
 
 This ingenious and very useful lock is represented, so far 
 as regards its governing principle, in fig. 25. The bolt is here 
 seen to have a peculiar slot or hole cut in it, consisting of a 
 narrow horizontal passage or gating, with three notches above 
 it and three below it. These double notches might be avail¬ 
 able even for one tumbler only; but Barron used two or more 
 for the sake of additional security. In fig. 25 there are two 
 tumblers shewn, expressed by dotted lines; both are hinged to 
 
 D 
 
50 
 
 ON LOCKS. 
 
 fig. 25. Action of Barron’s tumbler-lock. 
 
 one pivot, both are raised by the same action of the hey, but 
 the stump on the one tumbler does not coincide in position 
 with that on the other. It will be seen that if the studs of the 
 tumblers rested in the lower notches, they would require to be 
 elevated to the level of the gating before the bolt could be 
 moved ; while, on the other hand, if lifted too high, the 
 stumps would be caught in the upper notches, and would 
 equally prevent the passage of the bolt. The tumblers are 
 unequally wide; and the bitt of the key is stepped or notched 
 in a corresponding way, that there may be one step fitted to 
 act upon each tumbler. Mr. Barron also adopted the reverse 
 arrangement of having the stump on the bolt, and the openings 
 in the tumblers; so that the principle of his patent may be 
 concisely expressed as being “ an arrangement to allow a 
 stump on the tumbler to pass through an opening in the bolt, 
 or a stump on the bolt to pass through an opening in the 
 tumbler.” 
 
 A very elaborate tumbler-lock, patented 23d February, 
 1790, by Mr. Rowntree, contrasts remarkably with the sim¬ 
 plicity of Barron’s lock. Mr. Rowntree’s lock consisted of 
 tumblers combined with revolving discs or wheels. Its me¬ 
 chanism may be understood from the following description 
 and engravings. The same letters refer to the same parts in 
 the several figures. 
 
 a a is the plate which encloses the whole mechanism of 
 the lock, and fastens it to the door ; b b is the bolt, guided in 
 its motion by sliding under the bridges cd; ee are pillars 
 
ON TUMBLER, OR LEVER LOCKS. 
 
 51 
 
 which support a plate covering the works ; f are the circular 
 wards surrounding the centre or key-pin ; and a shews the 
 position of the key, which, in turning round, acts in a notch r 
 in the bolt, and propels it; o, the tumbler, is a plate situated 
 beneath the bolt, and moving on a centre-pin at d; it has a 
 catch or stump e projecting upwards, which enters the notches 
 /°r 9 m the bolt, and thereby retains the latter for backward 
 
 fig. 28. 
 
 fig. 30. 
 
 Details of Rowntree’s tumbler-lock. 
 
 or forward motion, as the case may be ; h is a spring which 
 presses the tumbler forward. The key a, in turning round, 
 acts first against the part c c of the tumbler, and raises it so as 
 to remove the stump from the notches ; it can then enter the 
 notch r in the bolt, and move it. So far there is no particular 
 security; but Mr. Rowntree sought to obtain it by the follow¬ 
 ing means. There is a piece of metal h fixed to the lower side 
 of the tumbler, called the pin ; when the tumbler is caught in 
 either notch of the bolt, the pin applies itself to a cluster of 
 
52 
 
 ON LOCKS. 
 
 small wheels i, fitted on one centre-pin beneath the tumbler; 
 the edges of these wheels stop the pin, and prevent the tumbler 
 from being raised. But each wheel has a notch cut in its 
 circumference I; and it is only when the wheels are so placed 
 that all their notches he in a right line, that the pin can enter 
 this compound notch and allow the tumbler to rise. The 
 wheels must therefore be all adjusted to position ; and this is 
 effected by a number of levers k centred on one pin at k ; at 
 the opposite end each lever has a tooth m entering a notch in 
 the wheel belonging to it; so that when any lever is pressed 
 outward, it turns its wheel round. Now this pressure of the 
 levers is brought about by a spring n applied to each ; and when 
 so pressed, the levers rest against a pin o fixed in the plate. 
 The key is so cut as to determine the extent to which the 
 levers shall act upon the wheels. The key first operates from 
 the curved part pp of the levers k, and raising them, turns all 
 the wheels I at once into the proper positions ; in turning 
 further round, it then operates on the part c c of the tumbler, 
 causing the latter to rise and to release the bolt ; and in turn¬ 
 ing still further round, it (the key) seizes the notch r of the 
 bolt, and shoots it. The key is cut into steps of different 
 lengths, as shewn at v v ; each step operates on its respective 
 lever k in a different degree from the others ; the notch at s 
 acts upon the tumbler, and the plain part t moves the bolt. 
 
 We now proceed to notice the modern tumbler-lock. This 
 was arranged by Bird, whose patent, bearing date 29th October, 
 1790, was for a series of four double-acting tumblers, differ¬ 
 ing in no respect from those patented by Barron, and closely 
 resembling those in use at the present time in the best tum¬ 
 bler-locks. We will describe the modern tumbler-lock more 
 particularly when we have gone through a few historical 
 details on the subject. 
 
 Messrs. Mitchell and Lawton obtained a patent bearing 
 date 7th March, 1815, for a lock in which were combined 
 with the bolt and double-acting tumblers, a series of movable 
 wards) and a revolving curtain for closing the key-hole. The 
 
ON TUMBLER, OR LEVER LOCKS. 
 
 53 
 
 action of the wards was peculiar. On introducing any key 
 or instrument, and passing it round, a number of movable 
 wards or pieces were thrown out so as to prevent the key 
 from being turned back or withdrawn. It was necessary 
 therefore to pass round the key so as to unlock the lock, and 
 if that were not possible, as in the case of a false key being 
 used, it was held permanently, and could only be released by 
 destroying the lock. When the bolt was once shot, the wards 
 were carried up so-as to leave a clear passage for the key. 
 This lock does not appear ever to have come into use, on 
 account of the violence required in case a wrong key should 
 be used either by accident or design. 
 
 The detention of a wrong key in this lock appears to have 
 suggested the contrivance of a detector . This was first made 
 by Ruxton, whose patent is dated 14th May, 1816. His de¬ 
 tectors were of various kinds, the object of each kind being to 
 give information to the owner in case any one of the tumblers 
 should be overlifted in an attempt to pick the lock, which fact 
 would be discovered on the next application of the true key. 
 This is precisely the object of the detector in tumbler-locks at 
 the present day, and Ruxton accomplished it by somewhat 
 similar means. He also had a contrivance for holding a false 
 key, as in Mitchell and Lawton’s lock; and he recommended 
 this form of detector in the following words; “ It is true that in 
 this case the lock will have to be destroyed in order to open the 
 door: the result is frightful; but we think the more terrible 
 the result, the less likely would any one be to tamper with it.” 
 
 We now come to Chubb’s lock, patented 3d February, 1818, 
 which consisted of double-acting tumblers and a peculiar kind 
 of detector. . This lock has been made the subject of various 
 patents obtained in the years 1824, 1833, 1846, and 1847. 
 This lock* consists of six separate and distinct double-actino- 
 
 O 
 
 , r , T l h ® 1 ° C i k aW t0 be described is the latest and most complete form 
 o Chubb lock up to the date of the Great Exhibition. The various addi¬ 
 tions and alterations which have been made in the lock since that date will 
 be noticed in a subsequent chapter. 
 
54 
 
 ON LOCKS. 
 
 tumblers, all of which must be raised to a particular height, 
 neither more nor less, in order that the bolt may pass. It also 
 comprises a detector, by which, should any one of the tumblers 
 be lifted too high in an attempt to pick or open the lock by a 
 false key, it would be immediately detected on the next ap¬ 
 plication of the proper key. The tumblers are flat pieces of 
 iron or steel, with the plane of the surface vertical, and pivoted 
 at one end ; and the following is the mode in which the key, 
 the tumblers, and the bolt, are brought into mutual action. 
 
 The bolt shoots in and out of the lock in the usual way. 
 It has a square stud or stump riveted on one surface ; and it 
 is to furnish obstructions to the passage of this stud that the 
 tumblers are provided. All the six tumblers are pivoted to 
 one pin at the end, giving to each of them a small leverage, 
 each independent of the others. There are six springs which 
 press these tumblers downwards, one to each tumbler. There 
 is a longitudinal slot or gating in each tumbler, large enough to 
 receive the stud of the bolt; and unless all the six slots (sup¬ 
 posing there to be six tumblers) coincide in height or position, 
 the stud will not have a clear passage for moving to and fro. 
 Now the slots are purposely made nearer the upper edge in 
 some of the tumblers than in others, all the six being different 
 in this respect; so that if they are all lifted equally, the slots 
 do not coincide, and the bolt and its stud will not pass. The 
 tumblers must then be raised unequally, those to be most raised 
 which have the slot nearest to the lower edge. To effect this, 
 the bit of the key is cut into six steps or inequalities, each to 
 act upon one particular tumbler, and each cut or stepped to the 
 exact depth which will suffice for the proper raising of the 
 tumbler. The key is inserted in the keyhole, and is turned ; 
 the six steps raise the six tumblers all to the proper height, to 
 leave a clear passage along the slots ; and the extreme end of 
 the key then acts upon the bolt itself, and shoots it. To unlock 
 it again, the same or a duplicate key must be used ; for if ano¬ 
 ther key be employed, differing by ever so little from the proper 
 one, some one or more of the tumblers will be lifted either a 
 
ON TUMBLER, OR LEVER LOCKS. 
 
 55 
 
 little too much or not quite enough ; and in either case the stud 
 of the bolt will catch above or below the slot, instead of having 
 a clear line of movement along the slot itself. After both lock¬ 
 ing and unlocking, the springs force the tumblers down as far 
 as they can go, burying the stud in the recesses above the slot; 
 so that the tumblers must be raised by the key both for lock¬ 
 ing and unlocking. 
 
 The doctrine of chances has wide play in determining the 
 relative position of the six tumblers. In Mr. Chubb’s essay 
 this part of the subject is treated in the following way: “ The 
 number of changes which may be effected on the keys of a 
 three-inch drawer-lock islx2x3x4x5x 6 = 720, the num¬ 
 ber of different combinations which may be made on the six 
 steps of unequal lengths (on a six-tumbler lock), without alter¬ 
 ing the length of either step. The height of the shortest step 
 is, however, capable of being reduced 20 times ; and each time 
 of being reduced, the 720 combinations may be repeated; 
 therefore 720 x 20 = 14,400 changes. The same process, after 
 reducing the shortest step as much as possible, may be gone 
 through with each of the other five steps ; therefore 14,400 x 6 
 = 86,400, which is the number of changes that can be produced 
 on the six steps. If, however, the seventh step, which throws 
 the bolt, be taken into account, the reduction of it only ten 
 times would give 86,400 x 10 = 864,000, as the number of 
 changes on locks with the keys all of one size (that is, with 
 one key of definite size in all save the lengths of the steps). 
 Moreover, the drill pins of the locks and the pipes of the keys 
 may be easily made of three different sizes ; and the number 
 of changes will then be 864,000 X 3 = 2,592,000, as the whole 
 series of changes which may be gone through with this key. 
 In smaller keys, the steps of which are capable of being reduced 
 only ten times, and the bolt-step only five times, the number of 
 combinations will be 720 x 10x6x5x3 = 648,000. On the 
 other hand, in larger keys, the steps of which can be reduced 
 thirty times, and the bolt-step twenty times, the total number of 
 combinations will be 720 x 30 x 6 X 20 x 3 = 7,776,000.” 
 
56 
 
 ON LOCKS. 
 
 These enormous numbers have been the cause of much 
 of the wonderment which the six-tumbler locks have excited; 
 and, as we shall see further on, the Bramah lock presents still 
 more of the marvellous in respect to this ringing of the 
 changes. 
 
 The construction and action of the Chubb lock may be 
 further illustrated by means of an engraving, fig. 31, in 
 which b is the bolt of the lock, with a stump riveted to .it 
 marked s. The six tumblers are shewn perspectively, the 
 front or anterior one being marked t; they all move on the 
 centre-pin a, but are nevertheless perfectly distinct and sepa¬ 
 rate, to allow of being elevated to different heights. At d is 
 shewn one end of a divided spring, the divisions being equal 
 
 fig. 31. Chubb look, with detector and six tumblers. 
 
 to the number of tumblers, one to each, and so bent that each 
 spring may press upon its particular tumbler. At e is the de¬ 
 tector-spring, so placed that a projecting piece in the hindmost 
 tumbler shall be near it; this tumbler having also fixed into 
 it a stud or pin p. This being the arrangement, especially in 
 relation to the stump s and the tumblers, it follows that all 
 the tumblers must be lifted to exact and regulated heights in 
 order that the stump may pass through the longitudinal slits 
 of the tumblers; unless it can do so, the bolt cannot be with¬ 
 drawn. As there are gaps or notches in each tumbler both 
 
ON TUMBLER, OR LEVER LOCKS. 57 
 
 above and below the proper line of passage, and as there are 
 no ordinary means of ascertaining when any one tumbler is 
 lifted too high or not high enough, the safety of the lock is 
 greatly increased by this uncertainty; especially when it is 
 considered that this uncertainty is multiplied sixfold by the 
 different modes in which the six tumblers are slotted. If, 
 through the insertion of a false key, or by any other cause, 
 any one of the tumblers be raised above its proper position, 
 the detector spring e will catch the hindmost tumbler, and re¬ 
 tain it so as to prevent the bolt from passing; and thus, upon 
 the next application of the true key, it will be instantly felt 
 that some one of the tumblers has been overlifted, because the 
 true key will not unlock it. To relieve the bolt from this 
 temporary imprisonment, the key must be turned the reverse 
 way, as for locking; all the tumblers will thus be brought to 
 their proper position, and allow the stump to enter the notches 
 nn; the bevelled part of the bolt will then lift up the detector- 
 spring, and allow the hindmost tumbler to fall down into its 
 proper place; and all this being effected, the lock may be 
 opened and shut in the ordinary way. The pin p is so ad¬ 
 justed that if any one of the tumblers—front, back, or inter¬ 
 mediate—be lifted too high, the pin will be lifted with it, and 
 will catch into the detector-spring, thus producing the result 
 just described. 
 
 The key is represented in fig. 32. It has six steps, be¬ 
 sides a terminal step to act upon the bolt. 
 
 The height of each step, or the distance to 
 which it extends from the pipe of the key, 
 depends of course on the height to which 
 its corresponding tumbler is to be lifted; 
 and it matters not whether the steps of the 
 key are adjusted to the slots of the tumblers, 
 or the slots to the steps, provided the agree¬ 
 ment be brought about. It is simply a matter 
 of manufacturing convenience that the key- 
 steps are cut first and the tumbler-slots after- Key to Chubb’s lock. 
 
 D 2 
 
58 
 
 ON LOCKS. 
 
 wards. We may here remark that bit, or bitt, is the name 
 given, somewhat indefinitely, either to the whole flat part 
 of a key, or to the small stepped portions of it. The 
 flat part was formerly termed the web of the key, probably 
 from the webbed appearance of the keys to complex warded 
 locks. 
 
 After the reading of Mr. Chubb’s paper before the Institu¬ 
 tion of Civil Engineers, Mr. Owen narrated one or two circum¬ 
 stances connected with the early history of Chubb’s lock. A 
 convict on board one of the prison-ships at Portsmouth dock¬ 
 yard, who was by profession a lock-maker, and who had been 
 employed in London in making and repairing locks for several 
 years, and subsequently had been notorious for picking locks, 
 asserted that he had picked with ease one of the best of Bra¬ 
 mah’s locks, and that he could pick Chubb’s locks with equal 
 facility. One of the latter was secured by the seals of the 
 late Sir George Grey, the Commissioner, and some of the 
 principal officers of the dockyard, and given to the convict, 
 together with files and all the tools which he stated were 
 necessary for preparing false instruments for the purpose, as 
 also blank keys to fit the pin of the lock. A lock exactly the 
 same in principle was placed in his hands, that he might ex¬ 
 amine it and make himself master of its construction. If he 
 succeeded in opening the lock, he was to receive a free pardon 
 from the Government, and a reward of 100/. from Messrs. 
 Chubb. After trying for two or three months to pick the 
 sealed lock—during which time, by his repeated efforts, he 
 frequently over-lifted the detector, which was as often re¬ 
 adjusted for his subsequent trials—he gave up the attempt. 
 He stated that Chubb’s were the most secure locks he had 
 ever met with, and that it was impossible for any man to pick 
 or to open them with false instruments. 
 
 Mr. Owen further stated, that in ord,er to compare the 
 merits of Bramah’s and Chubb’s locks, he hgd suggested a me¬ 
 chanical contrivance, which was applied to ope of Bramah’s 
 six-spring padlocks belonging to the Excise, It was hung 
 
ON TUMBLER, OR LEVER LOCKS. 
 
 59 
 
 upon a nail, in a vertical position, secure from lateral oscilla¬ 
 tion. A self-acting apparatus was then applied, consisting of 
 a pipe with hexagonal grooves, and a stud or bit correspond¬ 
 ing with the division of the lock, and secured to it by a spring. 
 In the grooves of this pipe small slides were inserted, which 
 pressed against the spring keys of the lock; to these slides were 
 attached levers, acted upon by eccentrics, moved by a combina¬ 
 tion of wheels, whose teeth differed in number so as to perform 
 the permutation required for the different depths of the spring 
 keys, corresponding with those of the proper key to the lock. 
 The automaton machine was set in motion by a line working 
 over a barrel, and acted upon by a weight; and was thus left 
 acting upon the mechanism for a considerable time. At right 
 angles to the pipe or false key was attached a rod and weight; 
 and when the notches in the spring keys were brought in a 
 line with the plane of the plate or diaphragm of the lock, the 
 rod and weight turned the false key, opened the lock, and 
 stopped the further motion of the automaton. In that state 
 the slides indicated the exact depth of the grooves in the proper 
 key, and gave the form of a matrix by which to make a key 
 similar to the original one. The automaton worked during a 
 period varying from half an hour to three hours, according to 
 the state of permutation of the apparatus at the moment of 
 being applied, compared with that of the slides in the lock. 
 We confess that it is difficult to understand the action of this 
 automaton from Mr. Owen’s description. We imagine that 
 the false notches would effectually prevent the operation of 
 the instrument, and openings would be required on eaph slide 
 to bring it back, so as to meet the motions of the machine, 
 
 Mr. Owen did not state whether his apparatus had been 
 successful with one only of Bramah’s locks or with several; 
 nor did he describe any apparatus invented with the view to 
 the picking of Chubb’s locks. He stated, however, that in 
 order to ascertain the effect of friction on one of these last- 
 named locks, it was subjected to the alternate rectilinear motion 
 of a steam-engine in Portsmouth dockyard, and was locked 
 
60 
 
 ON LOCKS. 
 
 and unlocked upwards of 460,000 times consecutively, without 
 any appreciable wear being indicated by a gauge applied to 
 the levers and the key, both before and after this alternate 
 action. Mr. Owen concluded by expressing his individual 
 opinion that Chubb’s lock had never been picked. “ The de¬ 
 tector was the main feature of its excellence; and additional 
 precaution, therefore, was only departing from its simplicity, 
 and adding to the expense, without any commensurate advan¬ 
 tage.” 
 
 In a subsequent chapter the degree of security afforded by 
 various descriptions of locks, and the obstacles which they 
 pi’esent of being picked, will come under notice; we therefore 
 now proceed to describe briefly a few other tumbler-locks, or 
 application of the tumbler-principle. 
 
 In Mr. Somerford’s lock, for which the Society of Arts gave 
 a premium in 1818, an attempt was made to improve upon 
 the ordinary action of tumblers. In most such locks, all the 
 tumblers must ascend, although to different heights, before 
 the stud of the bolt can pass through the slots; “ which ar¬ 
 rangement,” says Mr. Somerford, “ gives an opportunity of in¬ 
 troducing a nail, or a piece of stout wire, into the lock, and thus 
 raising the tumblers without the necessity of using the key.” 
 In his new lock, however, he made one lever to ascend while 
 the other descended, by a somewhat complicated arrangement 
 of slotted plates above and below the bolt. The key was so 
 perforated as to be much endangered in respect to strength. 
 
 In Davis’s lock there is a double chamber with wards on 
 the side of the key-hole. The key is inserted into the first 
 chamber and turned a quarter round; it is then pushed forward 
 into the inner chamber, where there is a rotating plate con¬ 
 taining a series of small pins or studs, which are laid hold 
 of by the key. By turning the key, the plate is moved round, 
 the tumbler is raised, and the bolt is shot backwards and 
 forwards. This lock, which is somewhat expensive, is used 
 to some extent on Cabinet despatch-boxes. 
 
 The lock invented by Mr. Nettlefold is so constructed, 
 
ON TUMBLES, OE LEVEE LOCKS. 
 
 61 
 
 that when the bolt is shot out by the key, two teeth or 
 quadrants are projected from the sides of the bolt, which take 
 a firm hold of the plate fixed on the door-post or edge. This 
 construction is said to answer well for sliding-doors. 
 
 Mr. Alfred Ainger, in 1820, received a silver medal from 
 the Society of Arts for a draw-back spring latch, in which the 
 objects proposed were the two following—to reader the lock 
 more difficult of violation by a pick than those ordinarily in 
 use ; and to apply to it a key of which no ordinary person 
 could take an impress, and which would be difficult of access 
 even in a workman’s hand. The key is very peculiar ; its 
 pipe consists of three divisions, the section of the upper and 
 lower divisions being circular, and that of the middle division 
 triangular ; the triangular portion is intended to give motion to 
 some part of the interior of the lock during the rotation of the 
 key. There are collars fixed on the extremity of the key, 
 to act each on one tumbler; and there are modes, by vary¬ 
 ing the arrangement of these collars on an octagonal stem, 
 to give something like a permutation to the number of varia¬ 
 tions to which the action of the key may be subject. The 
 notches or slots are rather in the bolt than in the tumblers ; 
 and there are many peculiarities in the general arrangement. 
 
 In a lock invented and patented by Mr. Parsons, the tum¬ 
 blers are of a particular form, being hinged on a pivot at their 
 centres, and working into and out of two notches cut in the 
 under side of the bolt. It must be obvious that many varia¬ 
 tions in the adjustment of the tumblers of locks might be made, 
 ■without vitiating the principle on which the action depends. 
 
 Many inventors have tried the use of an expanding web 
 to the key, so planned that if the step of the jveb be long 
 enough to reach the tumbler, it would be too long to pass 
 through the key-hole ; and therefore a principle of safety would 
 operate by enabling the key to adjust itself at one moment to 
 the size of the key-hole, and at another to the height of the 
 tumbler. Mr. Machin of Wolverhampton invented such a key 
 in 1827. The web of the key is movable on a countersunk 
 
62 
 
 ON LOCKS. 
 
 pin, on which it can so far slide as to be drawn one-eighth of 
 an incli from the barrel. The key-hole is of such a size as to 
 admit the key only when the web is pressed close up to the 
 barrel. When the key in this state is introduced, and is begun 
 to be turned round, one of the notches in the web works into a 
 raised circular edge of steel, placed eccentrically with regard, 
 to the lock-pin; so that as the key is turned, the web becomes 
 drawn out, and is at its greatest elongation when it arrives at 
 the tumblers: in the second half of its circular movement, the 
 key becomes contracted to its original dimensions, and can then 
 be removed from the lock. 
 
 Another mode of modifying the key has been introduced 
 by Mr. Mackinnon, the object being to enable any person to 
 change at will the pattern or arrangement of the movable 
 parts of a lock and key; or to keep the key, when not actually 
 in use, in such a state as to render it unavailing to any one but 
 himself. It was a complex arrangement, which does not seem 
 to have come much into use. 
 
 The lock invented by Mr. Williams, in 1839, may be de¬ 
 signated a pin-lock, involving a principle analogous in many 
 points to that of the Egyptian lock. This lock has a series 
 of pins which reach through the cap, and are pressed to their 
 places with a key like a comb or a rake-head. On the inner 
 end of each pin is a flat piece of steel, in which is cut a notch 
 for the passage of the bolt; but this passage is not clear until 
 the notches in all the pieces of steel are in a right line. 
 The pins are movable, and can be pushed either too far or 
 not far enough to bring about the coincidenpe of position in 
 the notches ; and on this ground they are “ double-acting.” 
 Now the teeth of the key are of irregular lengths, each having 
 a length just suited for pushing the pin to the proper depth: 
 any other lengths of teeth' would fail to open the lock. There 
 is a mechanism of springs and levers to shoot the bolt when 
 the p}ns in the plate are rightly adjusted. The arrangements 
 in respect to the key are singular and somewhat awkward. 
 The teeth which lock the bolt are not the same as those 
 
ON TUMBLER, OR LEVER LOCKS. 
 
 which unlock it, the user having to change ends and ad¬ 
 just the bit to a socket-handle. This is one among many 
 examples in which a lock embodies several principles, the in¬ 
 ventor having set himself the task of combining the excellences 
 of many diverse locks. 
 
 In respect to the tumbler-locks generally, the simplicity 
 of action, the strength of construction, and the non-liability 
 of disarrangement, have given them a high place among 
 safety-locks. The only danger seemed to be, that any person 
 once obtaining possession of the key could take an impression 
 from it, and thence form a key which would command the 
 lock. Attempts have been occasionally made to obviate this 
 danger, by supplying the key with movable bits which could 
 be changed at pleasure, so as to constitute any number of 
 effectively different bits in succession. But the locks being 
 so constructed that the bolt could only be moved when the 
 tumblers were in a certain position, the owner was placed in 
 this predicament: that it was useless to alter the arrangement 
 of the bits in the key, unless the tumblers were altered in a 
 corresponding manner; and this would entail the removal of 
 the lock from the door, and the re-arrangement of the inte¬ 
 rior mechanism. 
 
 One of the great defects of tumbler-locks made previously 
 to the last ten years was, that the tumblers, when lying at 
 rest in the lock, presented at their bellies or lower edges pre¬ 
 cisely the same arrangement as the steps of the key. Indeed, 
 in many locks of the present day, a good idea of the form of 
 the key may be gained by feeling the bellies of the tumblers. 
 The bellies are in fact cut out so as to compensate for the 
 circular motion of the key, to allow them to remain at rest 
 while the stump is passing through the gating. Even in 
 tumbler-locks of the best construction the tumblers will vibrate 
 more or less during the motion of the key; a defect which 
 must be provided against in adjusting the lock, or the stump 
 «dll be caught in its passage through the gating. Mr. Hobbs 
 provides a simple remedy by enlarging the back part of the 
 
64 
 
 ON LOCKS. 
 
 gating, the effect of which is as follows : when, in shoot¬ 
 ing back the bolt, as in unlocking, the key has got to its 
 highest point, the stump enters the narrow end of the gating; 
 but in shooting the bolt forward, as in locking, the stump 
 enters the gating before the key has got to its highest point, 
 and to allow for the slight vibratory motion of the tumblers 
 during the passage of the stump, the gating is widened. The 
 usual method of adjustment is to alter the forms of the bellies 
 of the tumblers, thus greatly risking the security of the lock, 
 a defect which was clearly perceived by Bramah [see pp. 
 67-70], and was one of the reasons which induced him to 
 construct locks with slides instead of tumblers. 
 
 American locks on the tumbler-principle, and the relation 
 which all such locks bear to the Bramah lock, will be better 
 understpod after the details of the following chapter. 
 
 CHAPTER VI. 
 
 THE BRAMAH LOCK. 
 
 The lock which was invented by the late Mr. Bramah de¬ 
 servedly occupies a high place among this class of contrivances. 
 It differs very materially from all which has gone before it; 
 its mechanical construction is accurate and beautiful; its key 
 is remarkable for smallness of size; and the invention was 
 introduced by the publication of an essay containing much 
 sensible observation on locks generally. The full title of this 
 essay runs thus: “ A dissertation on the Construction of Locks. 
 Containing, first, reasons and observations, demonstrating all 
 locks which depend upon fixed wards to be erroneous in prin¬ 
 ciple, and defective in point of security. Secondly, a speci¬ 
 fication of a lock, constructed on a new and infallible principle, 
 which, possessing all the properties essential to security, will 
 
THE BRAMAH LOCK. 
 
 65 
 
 prevent the most ruinous consequences of house-robberies, 
 and be a certain protection against thieves of all descriptions.’’ 
 A second edition of this Dissertation was published in 1815; 
 but the work is now extremely scarce, and hardly attainable. 
 
 It is remarkable to observe the boldness and self-relying 
 confidence with which Mr. Bramah, some sixty years ago, de¬ 
 clared that all locks were, up to that time, violable; he felt 
 that this was strictly true, and he hesitated not to give 
 expression to his conviction. The following is from \is 
 Dissertation :— 
 
 “ ^ observable that those who are taken in the desperate 
 occupation of house-breaking are always furnished with a 
 number and variety of keys or other instruments adapted to 
 the purpose of picking or opening locks ; and it needs no 
 argument to prove that these implements must be essential 
 to the execution of their intentions. For unless they can 
 secure access to the portable and most valuable part of the 
 effects, which in most families are deposited under the imagin¬ 
 ary security of locks, the plunder would seldom recompense 
 the difficulty and hazard of the enterprise; and till some 
 method of security be adopted by which such keys and in¬ 
 struments may be rendered useless, no effectual check or op¬ 
 position can be given to the excessive and alarming practice of 
 house-breaking. 
 
 . confident that I have contrived a security which 
 
 no instrument but its proper key can reach; and which 
 may be so applied as not only to defy the art and ingenuity 
 of the most skilful workman, but to render the utmost force 
 ineffectual, and thereby to secure what is most valued as 
 well from dishonest servants as from the midnight ruffian 
 I think myself at liberty to declare (what nothing but the 
 discovery of an infallible remedy would justify my disclosing 
 that all dependence on the inviolable security of locks, even 
 rf those which are constructed on the best principle of any 
 n general use, is fallacious. To demonstrate this bold and 
 ilarming proposition, I shall first state the common principles 
 
66 
 
 ON LOCKS. 
 
 which are applied in the art of lock-making; and by describ¬ 
 ing their operation in instruments differently constructed, 
 prove to my intelligent readers that the best-constructed locks 
 are liable to be secretly opened with great facility; and that 
 the locks in common use are calculated only to induce a false 
 confidence in their effect, and to throw temptation to dis¬ 
 honesty in the way of those who are acquainted with their 
 imperfections, and know their inefficacy to the purpose of 
 security” (p. 5). 
 
 Tumblers had been so little thought of and used at the 
 time Bramah wrote, that his attention was almost exclusively 
 directed to warded locks. The mysterious clefts in a key, 
 connected with some kind of secret mechanism in the lock, 
 had given the warded locks a great hold on the public 
 mind, as models of puzzlement and security; and it was to 
 shew that this confidence rested on a false basis, that he to 
 a great extent laboured. The following is his exposition of 
 the principle and the defects of the warded lock. 
 
 “ Locks have been constructed, and are at present much 
 used and held in great esteem, from which the picklock is 
 effectually excluded; but the admission of false keys is an 
 imperfection for which no locksmith has ever found a cor¬ 
 rective; nor can this imperfection be remedied whilst the pro¬ 
 tection of the bolt is wholly confided to fixed wards. For if a 
 lock of any given size be furnished with wards in as curious 
 and complete a manner as it can be, those wards being neces¬ 
 sarily expressed on what is termed by locksmiths the bit or 
 web of the key, do not admit of a greater number of variations 
 than can be expressed on that bit or web; when, therefore, 
 as many locks have been completed of the given size as will 
 include all the variations which the surface of the bit will 
 contain, every future lock must be the counterpart of some 
 former one, and the same key which opens the one will of 
 course unlock the other. It hence follows that every lock which 
 shall be fabricated on this given scale, beyond the number at 
 which the capability of variation ends, must be as subject to 
 
THE BRAMAH LOCK. 
 
 67 
 
 the key of some other lock as to its own; and both become 
 less secure as their counterparts become more numerous. 
 This objection is confirmed by a reference to the locks com¬ 
 monly fixed on drawers and bureaus, in which the variations 
 are few, and these so frequently repeated, from the infinite 
 demand for such locks, that, even if it were formed to resist 
 the picklock, they would be liable to be opened by ten thou¬ 
 sand correspondent keys. And the same observation applies 
 in a greater or less degree to every lock in which the variations 
 are not endless. 
 
 “ But if the variation of locks in which the bolt is guarded 
 only by fixed wards could be multiplied to infinity, they would 
 afford no security against the efforts of an ingenious locksmith; 
 for though an artful and judicious arrangement of the wards, 
 or other impediments, may render the passage to the bolt so 
 intricate and perplexed as to exclude every instrument but its 
 proper key, a skilful workman having access to the entrance 
 will be at no loss to fabricate a key which shall tally as per¬ 
 fectly with the wards as if the lock had been open to his in¬ 
 spection. And this operation may not only be performed to 
 the highest degree of certainty and exactness, but is conducted 
 likewise with the utmost ease. For the block or bit, which is 
 intended to receive the impression of the wards, being fitted to 
 the keyhole, and the shank of the key bored to a sufficient 
 depth to receive the pipe, nothing remains but to cover the 
 bit with a preparation which, by a gentle pressure against the 
 introductory ward, may receive its impression, and thus fur¬ 
 nish a certain direction for the application of the file. The 
 block or bit being thus prepared with a tally to the first ward, 
 gains admission to the second; and a repetition of the means 
 by which the first impression was obtained, enables the work¬ 
 man to proceed, till by the dexterous use of his file he has 
 effected a free passage to the bolt. And in this operation he 
 is directed by an infallible guide; for, the pipe being a fixed 
 centre on which the key revolves -without any variation, and 
 the wards being fixed likewise, their position must be accu- 
 
68 
 
 ON LOCKS. 
 
 rately described on the surface of the bit which is prepared to j 
 receive their impression. The key therefore may be formed 
 and perfectly fitted to the lock without any extraordinary de- j 
 gree of genius or mechanical skill. It is from hence evident I 
 that endless variations in the disposition of fixed wards are not | 
 alone sufficient to the purpose of perfect security. I do not j 
 mean to subtract from the merit of such inventions, nor to ] 
 dispute their utility or importance. Every approach towards I 
 perfection in the art of lock-making may be productive of 
 much good, and is at least deserving of commendation; for if i 
 no higher benefit were to result from it, than the rendering j 
 difficult or impossible to many that which is still practicable 'j 
 and easy to a few, it furnishes a material security against | 
 those from whom the greatest mischiefs and dangers are to be I 
 apprehended.” 
 
 There can be little doubt, in the present day, that Bramah 
 did not over-rate the fallacies embodied in the system of wards ' 
 for locks. He was sufficiently a machinist to detect the weak 
 points in the ordinary locks; and, whatever may have been 
 his over-estimate of his own lock (presently to be described), 
 he was certainly guilty of no injustice to those who had pre¬ 
 ceded him; for their locks were substantially as he has de¬ 
 scribed them. To understand the true bearings of his Dis¬ 
 sertation too, we must remember that housebreaking had risen 
 to a most daring height in London at the time he wrote (about 
 the middle of the reign of George HI.); and men's minds were 
 more than usually absorbed by considerations relating to their 
 doors and locks. 
 
 Mr. Bramah, after doing due justice to the ingenuity of 
 Barron’s lock, in which, if the tumbler be either over lifted or 
 under lifted the lock cannot be opened, pointed out very clearly 
 the defective principle which still governed the lock. “ Greatly 
 as the art is indebted to the ingenuity of Mr. Barron, he has 
 not yet attained that point of excellence in the construction of 
 his lock which is essential to perfect security. His improve¬ 
 ment has greatly increased the difficulty but not precluded the 
 
THE BE AMAH LOCK. 
 
 69 
 
 I possibility of opening bis lock by a key made and obtained as 
 above described (by a wax impression on a blank key); for an 
 impression of the tumblers may be taken by the same method, 
 and the key be made to act upon them as accurately as it may 
 be made to tally with the wards. Nor will the practicability 
 of obtaining such a key be prevented, however complicated 
 i the principle or construction of the lock may be, whilst the 
 | isposition of its parts may be ascertained and their impres¬ 
 sion correctly taken from without. I apprehend the use of 
 additional tumblers to have been applied by Mr. Barron as 
 a remedy for this imperfection.” Mr. Bramah thought that 
 Barron had a perception of a higher degree of security, but 
 a failed to realise it; because, by giving a uniform motion 
 to the tumblers, and presenting them with a face which tallies 
 exactly with the key, they still partake in a very great degree 
 o the nature of fixed wards, and the security of the lock is 
 
 thereby rendered in a proportionate degree defective and liable 
 to doubt. 
 
 To shew how this insecurity arises, Mr. Bramah illustrates 
 
 which T r m I*' f0ll ° Wing Wa ^ : “ Su PP ose the key with 
 which the workman is making his way to the bolt to have 
 
 passed the wards, and to be in contact with the most promi- 
 
 “ I , 6 tUmbIerS - The Session, which the slightest 
 
 fifo tl ^ ° Q the keJ ’ WiU direCt the a PP licati on of the 
 hie till sufficient space ig prepared to g . ve . t a free pags 
 
 Phis being accomplished, the key will of course bear upon the 
 tumbler which is most remote; and being formed by this pro- 
 s o ay with the face which the tumblers present, will 
 cquire as perfect a command of the lock as if it had been 
 originally made for the purpose. And the key, being thus 
 
 arisiS f a r nnS ° n ^ the tUmbIerS at ° DCe ’ the benefit 
 g rom the increase of their number, if multiplied by 
 
 act 7 ’ 7 S T7 Uy be l0St ’ f ° r ’ havin S but one motion, they 
 act only with the effect of one instrument.” 7 
 
 It is worthy of notice, that even while thus shewing the 
 
 *eak points of the Barron lock, Mr. Bramah seems to have 
 
70 
 
 ON LOCKS. 
 
 had in his mind some conception of infallibility or inviolability j 
 attainable by the lock in question. After speaking of the de- I 
 feet arising from the bad arrangement of the tumblers, he , 
 says: “But nothing is more easy than to remove this objec¬ 
 tion, and to obtain perfect security from the application of i 
 Mr. Barron’s principle. If the tumblers, which project un¬ 
 equally and form a fixed tally to the key, were made to pre¬ 
 sent a plane surface, it would require a separate and unequal 
 motion to disengage them from the bolt; and consequently i 
 no impression could be obtained from without that would give 1 
 any idea of their positions with respect to each other, or be of < 
 any use even to the most skilful and experienced workman in I 
 the formation of a false key. The correction of this defect | 
 would rescue the principle of Mr., Barron’s lock, as far as I 
 am capable of judging, from every imputation of error or im¬ 
 perfection ; and, as long as it could be kept unimpaired, would 
 be a perfect security. But the tumblers, on which its security i 
 depends, being of slight substance, exposed to perpetual fric- | 
 tion—as well from the application of the key as from their 
 own proper motion—and their office being such as to render 
 the most trifling loss of metal fatal to their operation, they l 
 would need a further exertion of Mr. Barron’s ingenuity to , 
 make them durable.” 
 
 ft may perhaps be doubted whether the principle of ; 
 Bramah’s lock is not more clearly shewn in the original con¬ 
 structed by him than in that of later date. In appearance it is 
 totally different, but the same pervading principle is observable 
 in both; and the cylinder lock can certainly be better under¬ 
 stood when this original flat lock has been studied. The 
 annexed woodcut is taken from the first and very scarce 
 edition of Mr. Bramah’s Dissertation; the description is some¬ 
 what more condensed, but perhaps sufficient for the purpose. 
 
 The lock is supposed to be lying flat, with the bolt b half¬ 
 shot. Iianged somewhat diagonally are six levers, turning on 
 a horizontal joint or pivot at A, each lever having a slight 
 extent of vertical motion independent of the others. Each 
 
THE BRAMAH LOCK. 
 
 71 
 
 lever rests' on a separate spring of sufficient strength to sus¬ 
 tain its weight, or, if depressed by a superior force, to restore 
 it to its proper position when the force is withdrawn, f is a 
 
 curved piece of metal, pierced with six grooves or passages; 
 these grooves are exactly equal in width to the thickness of the 
 levers, but are of sufficient depth to allow the levers a free 
 i motion in a perpendicular direction. The ends of the levers 
 are inserted in these grooves, and have this freedom of motion, 
 whether lifted by the elastic power of the springs or depressed 
 by a weight from above. In the bolt b is a notch to receive 
 a peculiarly-shaped lever, which shoots or withdraws the bolt 
 according as it traverses to the right or the left. This lever, the 
 six long levers, the springs beneath them, the bent piece f 
 and the pivot, all alike are fixed to a circular platform p, 
 which turns on a centre; so that if any force can make this 
 platform turn partially round, the bolt must be shot or unshot 
 >Y the lever which works in the notch. The six long levers 
 
72 
 
 ON LOCKS. 
 
 are the contrivances whereby the platform shall not be allowed 
 to turn until the proper moving agent (the key) shall have 
 been applied, the plate p being one of the assistants in this 
 obstruction. This plate, which is hollow underneath, has six 
 notches in one of its edges; the points of the levers catch into 
 these notches; and while so caught, the levers cannot move hori¬ 
 zontally, and all the machinery is at a stand-still. To enable 
 the key to set the mechanism in action, other contrivances 
 are necessary. Each lever has a notch at its extreme end, 
 and the six are notched very irregularly in respect one to 
 another. These notches must be brought all into one plane, 
 to enable the levers to pass horizontally out of the notches 
 in the plate, in the same way as the two prongs of a fork 
 might traverse one above and the other below the blade of a 
 knife; and when the lever-notches are in this position, all in 
 one plane and in the plane of the plate, the levers can be 
 moved, and with it the stump which shoots the bolt. To en¬ 
 sure this due pressing down of the levers, a key is used such 
 as is shewn in the cut, having six steps or bits to correspond 
 with the six levers ; this key, put upon the pin k, presses 
 down all the levers to the exact distance necessary for bring¬ 
 ing their notches into one plane, viz. the plane of the plate; 
 the key then being turned round turns the movable plat¬ 
 form p, and shoots the bolt. It is evident at a glance, that 
 unless the various steps of the key are so cut, that each shall 
 press down its own lever to the proper extent, the ends of the 
 levers cannot pass the notches in the plate, and the bolt can 
 neither be locked nor unlocked. 
 
 It may be well to give Bramah’s own words in relation to 
 this lock: “ I may safely assert that it is not in art to produce 
 a key or other instrument by which a lock constructed on 
 this principle can be opened. It will be a task, indeed, of 
 great difficulty, even to a skilful workman, to fit a key to this 
 species of lock, though its interior face were open to his in¬ 
 spection; for the levers being raised by the subjacent springs 
 to an equal height present a plane surface, and consequently 
 
THE BRAMAH LOCK. 
 
 73 
 
 convey no direction that can be of any use in forming a tally 
 to the. irregular surface which they present when acting in 
 subjection to the proper key. Unless, therefore, a method be 
 contrived to bring the notches on the ends of the levers in 
 a direct line with each other, and to retain them in that position 
 till an exact impression of the irregular surface which the levers 
 will then exhibit can be taken , the workman will in vain 
 attempt to fit a key to the lock, or by any effort of art to 
 move the bolt. And when it is considered that this process 
 wifi be greatly impeded, and may perhaps be entirely frus¬ 
 trated, by the action of the springs, it must appear that great 
 patience and perseverance, as well as great ingenuity, will be 
 required to gice any chance of succeeding in the attempt. 
 
 I do not state this circumstance as a point essential or of any 
 importance to the purpose of the lock, but to prove more 
 clearly what I have before observed upon its principle and 
 properties; for if such difficulties occur to a skilled workman, 
 as to render it almost, if not altogether impracticable to form 
 a key when the lock is open to his inspection and its parts 
 accessible to his hand, it pretty clearly demonstrates the im¬ 
 possibility of accomplishing it when no part of the movement 
 can be touched or seen.” 
 
 It is evident that Mr. Bramah had his thoughts directed 
 to that mode of picking locks which depends on taking im¬ 
 pressions of the moving parts, rather than to the mechanical or 
 pressure method which has been developed in later times. 
 There can be little doubt that a lock was, to his mind, a 
 beautiful and admirable machine, far elevated above the level 
 of mere blacksmith’s work; and his name will ever be asso¬ 
 ciated with what may be termed the philosophy of lock-making. 
 
 After the model-lock, which has just been described, was 
 constructed, and found to corroborate the idea which was 
 working in Mr. Bramah’s mind, he proceeded to the construc¬ 
 tion of his barrel or cylinder-lock, embracing similar elements 
 placed in more convenient juxta-position. In his Essay he 
 Jives an engraving to illustrate the principle on which his lock 
 
 E 
 
74 
 
 ON LOCKS. 
 
 acts, rather in the manner of a diagram than as depicting any 
 lock actually made; his main object being to impart a clear 
 notion of the action of the slides which form such a distin¬ 
 guishing feature in his lock. 
 
 fig. 34. Diagram to illustrate the Bramah lock. 
 
 Viewed in this sense, therefore, simply as an illustrative 
 diagram, the annexed cut may represent the action of the 
 safety slides, b is a sliding bar or bolt, having a power of 
 longitudinal motion in the frame F. This frame has six 
 notches cut on each of its long sides, the two series being 
 exactly opposite each other; and there are six similar notches 
 cut in the bolt b. The concurrent effect of all these eighteen 
 notches is, that the six slides abodef can move freely up and 
 down across the bolt. When the slides are thus placed, the bolt 
 cannot move, and may in this case be considered to be locked. 
 There are six clefts or notches in the six slides, one to each 
 (1, 2, 3, 4, 5, 6); and until all these are brought in a right 
 line, the bolt cannot move through them. If a tally or key 
 be prepared, as shewn at t in the lower part of the cut, with 
 six projections, and if these projections thrust up the six 
 slides till their clefts rise to the plane of the bolt, then can 
 the bolt be withdrawn or the lock opened. This serves to 
 illustrate the relation between the slides and the key, as 
 carried out in the way now to be described. 
 
 One peculiarity of the Bramah lock is, that from the 
 
THE BRAMAH LOCIf. jrj 
 
 essential part of the apparatus being a barrel or cylinder, much 
 of the working can be conducted in the lathe; and this has 
 given a beauty to the details generally and deservedly admired. 
 Mr. Bramah when he worked on, the theory of his lock 
 
 hltfon bT' d aI T her * he « ° f 1S “ d and S 
 
 he -e of tumblers working on a pivot at one end; subs.itut- 
 
 way The TH “TT "ovel 
 
 forLd^f, 7 “ ramal ] ° Ck “V be considered as 
 
 anTtoel C ° n ? entnC brass b a-«ls, the outer one fined, 
 
 and the inner rotating within it. The inner barrel has a cro 
 
 jesting stud, which, while the barrel is rotating, comes in 
 
 and In!'! 7 T " ^ « *» *00.7 lock it; 
 
 and thus the stud serves the same purpose as the bit of an 
 
 ordinary key, rendering the construction of a bit to the 
 
 Bramah key unnecessary. If the barrel can be made to rotate 
 
 to the right or left, the bolt can be locked or unlocked- and 
 
 It zi’ ,h rT how *• 
 
 i~r , T , ey ’ " Iucl1 has a P1K «r hollow shaft, is inserted 
 
 there musfb 6 UP ” T T- ^ “ ‘' Kn *“™ d but 
 
 barrel befor th' ''7 ^ ustment of th e mechanism of the 
 
 L ens^rT Th T“? ° fAe ** and the ba «' aa - 
 
 ensured. The barrel has an external circular groove at 
 
 it hi 77 40 T - aXiS ’ P enetrati "i? t» a certain depth; and 
 
 end In th 7 “7“' ^todinal grooves, from end to 
 
 to slide r gr °° VeS thi “ P®** »f steel are able 
 
 to slnte m a direction parallel with the axis of the barrel 
 
 trflns P to to T W the foohmg-plate, is screwed in two 
 
 and Tthe ° ’ Concentri o ' ri ‘h the inner barrel; 
 
 -d at the same time occupying the external circular groove 
 
 of th inner barrel; this plate has notches, fitted in nLZr 
 
 size to receive the edges of the slides which work in the 
 
 W TlTnTr 1 TT ° f ‘ he ^ H ‘ MS Wera ‘he 
 
 gTves of the ll k l " ** ^ are ia ‘he 
 
 grooves of the locking-plate; but each slide has also a groove 
 
 d TtT T " bT h *° ‘ he «“* »f ‘hie entanXT 
 
 this gioove be brought to the plane of the locking. plate! 
 
76 
 
 ON LOCKS. 
 
 the barrel can be turned, so far as respects that individual 
 slide. All the slides must, however, be so adjusted that their 
 grooves shall come to the same plane; but as the notch is cut 
 at different points in the lengths of the several slides, the slides 
 have to be pushed in to different distances in the barrel, in 
 order that this juxta-position of notches may be ensured. 
 This is effected by the key, which has notches or clefts at the 
 end of the pipe equal in number to the slides, and made to 
 fit the ends of the slides when the key is inserted; the key 
 presses each slide, and pushes it so far as the depth of its cleft 
 will permit; and all these depths are such that all the slides 
 are pushed to the exact position where their notches all lie in 
 the same plane; this is the plane of the locking-plate, and the 
 barrel can be then turned. 
 
 This is the principle which Mr. Bramah adopted ; and we 
 have now to trace it, step by step, by means of illustrative 
 
 tig. 35. Exterior of a Bramah lock. 
 
 details. Fig. 35 represents the exterior of a box or desk lock, 
 one among many varieties which the Bramah lock presents. 
 a a shews the bolt, formed something like two hooks rising 
 out of a bar of metal, which bar has a backward and forward 
 motion upon the plate b b. The upper edge of this plate is 
 turned over at right angles, forming a small horizontal surface 
 through which two openings are cut to receive the two hooked 
 portions of the bolt. The movements of the bolt are otherwise 
 guided by the edges of square holes through which it works ; 
 
THE BRAMAH LOCK. 
 
 77 
 
 the holes being made in the edge-pieces of the lock, riveted to 
 the main plate. The bolt is further prevented from rising out 
 of its place by means of a plate of 
 metal c, which is secured to the edge- 
 pieces by two screws 1, 1, and by two 
 steadying pieces. This plate has on 
 its surface a cylindrical projection d, 
 which contains in effect all the work¬ 
 ing mechanism of the lock. The pins 
 4 4 are employed for securing a plate, 
 which we shall have to describe pre¬ 
 sently. When such a lock is fixed 
 upon a desk or box, the portion D 
 projects to a small distance through 
 a hole in the wood-work, forming in 
 itself a very neat escutcheon, with a 
 key-hole in the centre. 
 
 So much for the exterior. We 
 must now proceed to examine the in¬ 
 terior of the lock, especially the part 
 contained within the cylinder. In fig. 
 
 36, for convenience of arrangement, 
 the several parts are exhibited sepa¬ 
 rately, and as if the plane of the lock 
 were horizontal, with the key acting 
 vertically. The essential part of the 
 mechanism is a barrel or cylinder E , 
 pierced or bored with a cylindrical 
 hole down its centre. The inside of the bore has six narrow 
 
 fig. 36. .Details of the 
 Bramah lock. 
 
 grooves, cut parallel with the axis, and in the direction of 
 
 radii; the grooves are not cut through the thick¬ 
 ness of the cylinder, but leave sufficient substance 
 of metal for strength. In every groove is fitted a 
 steel slide of peculiar form, such as is shewn at a a 
 in fig. 37. Each slide is split in its thickness 
 (seen in section), so that it may move up and 
 down in its groove with a slight friction, and 
 
 d 
 
 fig. 37. 
 The slides. 
 
78 
 
 ON LOCKS. 
 
 thereby not fall simply by its mm weight. Each slide has 
 three small notches (3, 2, 3), the use of which will presently 
 appear. Keverting to fig. 36, the lower part of the opening 
 through the cylinder E is closed by a circular plate of metal, 
 fixed to it by two screws ; this plate is represented at F, in the 
 lower part of the figure. This plate has a vertical pin rising 
 from its centre (also seen at b, fig. 39), and serving as a key- 
 pin on which the pipe of the key may work or slide ; and it 
 has also a short circular stud c projecting from its under side, 
 and fitted to enter into a curved opening in the bolt presently 
 to be described. 
 
 The point to be now borne in mind is this, that if the 
 cylinder E turns round, the plate F will also turn round, and 
 with it the stud c; and as this stud works into the peculiarly 
 formed cavity d in a portion of the bolt (fig. 38), it causes the 
 
 bolt to be shot backwards or forwards. Now, in order to pre¬ 
 vent this rotating of the cylinder unless the proper key be em¬ 
 ployed, the following mechanism is introduced: the cylinder 
 has a groove cut round its circumference at e e, extending suffi¬ 
 ciently near to the internal bore to produce the desired effect 
 without too much weakening the metal. Into this notch is in¬ 
 troduced the thin circular plate of metal ff it being divided 
 into two halves for this purpose ; and when so placed, it occupies 
 the position shewn by the dotted portion e e. When this plate 
 is screwed to the case of the lock by the screws 4, 4, it cannot 
 of course turn round ; but the cylinder itself will or will not 
 
THE BKAMAH LOCK. 
 
 79 
 
 turn round according to the position of the slides. The plate 
 ff has six notches, 5, 5, 5, &c. in the inner edge or circle ; so 
 adjusted that, when the plate is in its place, the slides a a can 
 move up and down. The cylinder cannot move round in a 
 circle without carrying the slides with it; and these cannot so 
 move unless they are all depressed to such exact distances in 
 their respective grooves, that the deep notch of each slider 
 (shewn at 2 in fig. 37) shall come into the plane of the circular 
 plate : when all are so brought, the cylinder can be turned. If 
 any one of the slides be pressed down either too low or not low 
 enough, this turning of the cylinder cannot be effected, because 
 the slides will be intersected by the edges of the notches 5,5; 
 and it is the office of the key, therefore, to press all the six 
 slides down to the exact distances required. When the slides 
 are not pressed upon by the key, they are forced upwards to 
 the top of the cylinder by a spiral spring 6, coiled loosely round 
 the pin b; this pressure forces up a small collet, 7, on which 
 the upper part of the slides rest by a sort of step. 
 
 The first locks were made with a separate and independent 
 spring to each slide; but it is a very great improvement, the 
 introduction of one common spring to raise up the whole 
 number; because if a person attempts to pick the lock by 
 depressing the slides separately by means of any small pointed 
 instruments, and by chance brings two or more of them to the 
 proper depth for turning round, should he press any one too 
 low, it is difficult to raise it again without relieving the 
 spring 6, which immediately throws the whole number of 
 slides up to the top, and destroys all that had been done 
 towards picking the lock. Another improvement of this lock, 
 and one which very much increased the difficulty of picking, 
 and its consequent security, was the introduction of false 
 and deceptive notches cut in the sliders, as seen at 3, 3. It 
 was found that in the attempt to pick this lock, an instrument 
 was introduced by the keyhole to force the cylinder round. 
 At the same time that the slides were depressed by separate 
 instruments, those slides which were not at the proper level 
 
80 
 
 ON LOCKS. 
 
 for moving round were held fast by the notches 5, 5 in the 
 plate f f bearing against their sides; but when pressed down 
 to the proper level, or till the notch 2 came opposite ff they 
 were not held fast, but were relieved. This furnished the 
 depredator with the means of ascertaining which slides were 
 pressed low enough, or to the point for unlocking. The 
 notches 3, 3 in the slides are sometimes cut above the true 
 notch 2, sometimes below, and at other times one on each side 
 (one above and one below) ; they are not of sufficient depth to 
 allow the cylinder to turn round, but are intended to mislead 
 any one who attempts to pick, by his not knowing whether it 
 is the true notch or otherwise, or even whether the slider be 
 higher or lower than the true notch. 
 
 We have not yet sufficiently described the key of the 
 Bramah lock. One merit of the lock is the remarkable small¬ 
 ness of the key, which renders it so conveniently portable. The 
 key, as shewn in the upper part of the figure, has six notches 
 or clefts at the end of its pipe or barrel; these clefts are cut to 
 different depths, to accord with the proper extent of movement 
 in the slides. There is a small projection, 10, near the end of 
 the pipe, fitted to enter the notch d in the cylinder; this forces 
 the cylinder round when the parts are all properly adjusted. 
 The bolt of the lock, when properly shot or locked, is pre¬ 
 vented from being forced back by the stud c on the bottom, F, 
 of the cylinder coming into a direct line with its centre of mo¬ 
 tion, as shewn in fig. 39; in this position no force, applied to 
 drive the bolt back, would have any tendency to turn the 
 cylinder round. 
 
 To facilitate the comprehension of this very curious and 
 beautiful mechanism, the cylinder is shewn in section in the 
 annexed fig. 39, the same letters and figures of reference being 
 used as before. In the whole of this description we have 
 spoken of six slides, and six only; but Bramah locks may be, 
 and have been, constructed with a much larger number. 
 
 There have been several attempts made to modify the 
 action of Bramah’s lock, or to combine this action with that of 
 
THE BRAMAH LOCK. 
 
 81 
 
 fig. 39. Section of the Bramah cylinder. 
 
 some other inventor. It will suffice to describe one of these. 
 The lock invented by Mr. Kemp of Cork, and for which a 
 patent was obtained in 1816, is called by him the Union lock, 
 as combining the principles of Barron’s and Bramah’s locks. It 
 contains two, three, or more sliders or tumblers, operated upon 
 by two, three, or more concentric tubes. These concentric 
 tubes are of different lengths, and are placed inside the barrel 
 of the key; so that the barrel may, in fact, be conceived to 
 consist of a series of concentric tubes. These tubes are made 
 of such respective lengths as to push back the tumblers, 
 sliders, or pins which detain the bolt; and this to the precise 
 extent that will bring certain notches in all the sliders to the 
 position which will allow the bolt to pass. The inventor gives 
 this lock its distinctive appellation because it combines some¬ 
 thing of the pushing motion which Bramah gives to his key, 
 with something of the tumbler-motion observable in Barron’s 
 locks. The principle of safety is considered here to rest chiefly 
 on the extreme difficulty of imitating the key. 
 
 Mr. Bramah calculates the number of changes of position 
 which the slides of his lock are capable of assuming before the 
 right one would be attained. “ Let us suppose the number 
 of levers, slides, or other movables by which the lock is kept 
 shut, to consist of twelve, all of which must receive a different 
 and distinct change in their position or situation by the appli¬ 
 cation of the key, and each of them likewise capable of receiv¬ 
 ing more or less than its due, either of which would be suffi- 
 
 e 2 
 
82 
 
 ON LOCKS. 
 
 cient to prevent the intended effect. It remains, therefore, to 
 estimate the number producible, which may be thus attempted. 
 Let the denomination of these slides be represented by twelve 
 arithmetical progressionals; we find that the ultimate number 
 of changes that may be made in their place or situation is 
 479,001,600; and by adding one more to that number of slides, 
 they would then be capable of receiving a number of changes 
 equal to 6,227,020,800; and so on progressively, by the addi¬ 
 tion of others in like manner to infinity. From this it appears 
 that one lock, consisting of thirteen of the above-mentioned 
 sliders, may (by changing their places only, without any dif¬ 
 ference in motion or size,) be made to require the said im¬ 
 mense number of keys, by which the lock could only be 
 opened under all its variations.” 
 
 CHAPTER VII. 
 
 AMERICAN LOCKS. 
 
 The lock-manufacture in America has undergone some such 
 changes as in England. The insufficiency of wards to the at¬ 
 tainment of security has been for many years known ; and the 
 unfitness of even tumblers to attain this end, without auxiliary 
 contrivances, has been fully recognised for a dozen years back. 
 In this, and in other mechanical arts, the American machinists 
 depended primarily on the invention of the artisans in the 
 mother country, rather than on those of any continental Eu¬ 
 ropean state. But the development of the art in the United 
 States has not been wanting in originality; the varieties of 
 locks have been very numerous, and many of them exceedingly 
 ingenious. It is not necessary, however, to describe or depict 
 any of those of simple form. The warded locks of different 
 countries very much resemble each other ; the intricate warded 
 
AMERICAN LOCKS. 
 
 83 
 
 locks made in France in the last century have long fallen into 
 disuse, in consequence of the general conviction that no arrange¬ 
 ment of wards, however intricate, can afford the degree of se¬ 
 curity required in a good lock. It will be more to the purpose, 
 therefore, to proceed at once to a notice of those American locks 
 which, during the last few years, have acquired some celebrity; 
 first, however, noticing one of older date. 
 
 Stansbury’s lock, invented in the United States about forty 
 years ago, may be regarded as a modification of the Egyptian 
 lock. It had a bolt, case, and key-hole somewhat similar to 
 those of modern locks ; but there were peculiarities of construc¬ 
 tion in other respects. There was a revolving plate, pierced 
 with a series of holes, and having a bit or pin which moved 
 the bolt. On the lock-case were a series of springs, each 
 having a pin at one end ; and the arrangement was such that, 
 when the bolt was locked or unlocked, each pin would be 
 pressed into some one of the holes. Like as in the Egyptian lock 
 (figs. 1 to 4), each pin had to be pushed out, and all of them 
 simultaneously, to allow the plate to turn and move the bolt. 
 The key was made with a barrel and bit; and on the front end 
 of the bit was a series of pins corresponding in position with 
 the holes in the plate. The mode of locking or unlocking was 
 as follows : the key was inserted in the key-hole, and turned 
 to a certain position; it was then pressed in with some force, 
 until the pins on the key met those in the plate ; when the 
 latter, yielding to the pressure, left the plate free to turn and 
 move the bolt. Modifications of the Egyptian lock, niore op 
 ♦less resembling this, have been brought out in some variety on 
 both sides of the Atlantic ; but scarcely any have equalled in 
 simplicity the curious wooden relic of by-gone ingenuity in the 
 art of lock-making. 
 
 A lock made a few years ago by Mr. Yale, in the United 
 States, somewhat resembles the Bramah lock in having a cylin¬ 
 der or barrel, or rather two concentric cylinders, one working 
 within the other. These cylinders are held together by pins 
 which pass through them both into the key-hole. On the back 
 
84 
 
 ON LOCKS. 
 
 of the inner cylinder is a pin that fits into a slot in the bolt, 
 and moves it whenever the cylinder is turned. The pins that 
 hold the cylinders together are each cut in two ; the pieces of 
 the various pins differing in lengths as irregularly as possible. 
 The key is so peculiarly formed, that, on inserting it in the 
 key-hole, it thrusts the pins radially outwards ; each pin being 
 pushed just so far that the joint of the pin shall coincide 'with 
 the joint between the two cylinders. The inner cylinder can 
 then be turned, by which the bolt is locked or unlocked. If, 
 by the use of a false key, any pin be pushed in too far, it will 
 be as ineffectual in opening the lock as if it were not thrust in 
 far enough ; and some of these locks having been made with as 
 many as forty pins, the chances are very numerous against the 
 right combination being hit upon. There is a combination of 
 something like the Egyptian with something like the Bramah 
 lock, here attempted. 
 
 One of the principal constructions adopted in America 
 a few years back for bank-locks is that of Dr. Andrews of 
 Perth Amboy, in New Jersey. It was up to that time (1841) 
 believed that the best locks, both of England and America, 
 were proof against any attempts at picking derived from know¬ 
 ledge obtained by Inspection through the key-hole ; but there 
 still remained the danger that the sight of the true key, or the 
 possession thereof, for only a few minutes, would enable a dis¬ 
 honest person to produce a duplicate. It was to contend against 
 this difficulty that Dr. Andrews directed his attention ; and he 
 sought to obtain the desired object by constructing a lock, the 
 interior mechanism of which could be changed at pleasure. 
 The lock of his invention is furnished with a series of tumblers 
 and a detector. The tumblers are susceptible of being arranged 
 in any desired order ; and the key lias movable bits which can 
 be arranged so as to correspond with the tumblers. When the 
 lock is fixed in its place, no change can be made in the tum¬ 
 blers, and consequently only one arrangement of the bits of the 
 key will suit for the shooting and withdrawing of the bolt. 
 The owner can, however, before the fixing of the bolt, adopt 
 
AMERICAN LOCKS. 
 
 85 
 
 any arrangement of tumblers and bits which he may choose. 
 But though the tumblers cannot be actually re-arranged in any 
 new order within the lock while the latter is fixed, yet by an 
 ingenious contrivance the tumblers can be so acted upon as to 
 render the lock practically different from its former self. The 
 purchaser receives with his lock a series of small steel rings, 
 each ring corresponds in thickness with the thickness of some 
 one of the bits of the key ; so that, by suitable adjustment, any 
 one of the bits may be removed from the key, and a ring be 
 substituted in its place. The effect of this substitution is, that 
 the particular tumbler which corresponds with the ring is not 
 raised by it; it is drawn out with the bolt, as if it were part of 
 the bolt itself. Supposing the lock to be locked by this means, 
 the original key would not now unlock it; for one of the tum¬ 
 blers has now been displaced, and can only be re-adjusted by 
 the same ring which displaced it. If an attempt be made to 
 open the lock by the original key, or by the key in its original 
 adjustment, a detector is set in action, which indicates that a 
 false key or other instrument has been put into the lock. One, 
 or more than one, of the bits may be removed from the key, 
 and rings be substituted, and consequently one or more of the 
 tumblers may be disturbed in this peculiar way; so that the 
 lock may change its character in all those permutating varie¬ 
 ties which are so observable in most “ safety-locks.” The 
 shape of the tumblers is, of course, such as to facilitate this 
 action; they have each an elongated slot, and also two notches; 
 when a tumbler is raised by one of the bits of the key, one of 
 the notches closes around a stump fitted into the case of the 
 lock, and prevents the tumbler from being moved onward with 
 the bolt; but when a ring has been substituted for a bit on 
 the key, the tumbler cannot be raised at all ; it is carried on¬ 
 ward by a stump on the bolt. 
 
 Dr. Andrews is also the inventor of a lock which he terms 
 the snail-wheel lock. In this lock a series of revolving discs, 
 or wheels, taking the place of the tumblers, are mounted on a 
 central pin, on which the pipe of the key is inserted. .Each 
 
86 
 
 ON LOCKS. 
 
 disc lias a piece cut out of it, into which the bit of the key- 
 enters, and in turning round moves the discs according to the 
 various lengths of the steps on the key. On the outer edge of 
 each disc is a notch, and by the turning of the key all these 
 notches are brought into a line, so that a moveable tongue, or 
 toggle , attached to the bolt, falls into the notches; the key is 
 then turned the reverse way, by which means the bolt is 
 projected. 
 
 About the time when Dr. Andrews invented his first lock, 
 Mr. Newell, of the firm of Day and Newell of New York, con¬ 
 structed a lock which possessed the same distinctive peculiarity 
 as that of Andrews, viz. that the key might be altered any num¬ 
 ber of times without rendering it necessary to remove the lock 
 or change its internal mechanism. This was brought about, 
 however, in a different manner. Instead of having, as in the 
 Andrews lock, a two-fold movement to every tumbler, Mr. 
 Newell employed two sets of tumblers, the one set to receive 
 motion from the other, and having different offices to fill, to 
 be acted upon by the key in respect to the first series, and to 
 act upon the bolt in respect to the second. Calling these two 
 sets 'primary and secondary , the action of the lock may be briefly 
 described as follpws. A primary tumbler being raised to the 
 proper height by the proper bit in the key, raises the corre¬ 
 sponding secondary tumbler; the secondary tumbler is held 
 up in a given position during the locking, while the primary 
 becomes pressed by a spring into its original position. It re¬ 
 sults from this arrangement that the bolt cannot be unlocked 
 until the primary tumbler has been raised to the same height 
 as before, so as to receive the tongue of the secondary tumbler. 
 And as this is the case in respect to any one primary and its 
 accompanying secondary tumblers, so is it the case whether 
 each set comprises four, five, or any other number. The key 
 may be altered at pleasure, and will in any form equally well 
 shoot the bolt; but the lock can only be unfastened by that 
 arrangement of key which fastened it. 
 
 It is, however, desirable to trace the course of improve- 
 
AMERICAN LOCKS. 
 
 87 
 
 ments more in detail, because every successive change illus¬ 
 trates one or other of the several properties required in a good 
 lock. Messrs. Day and Newell’s lock was not finally brought 
 to an efficient form without many attempts more or less abor¬ 
 tive. Mr. Newell conceived the idea of applying a second 
 series of tumblers, so placed as to be acted on by the first 
 series. Each of these secondary tumblers had an elongated 
 slot, such that a screw could pass through all of them ; the 
 screw having a clamp to overlap the tumblers on the inside 
 of the lock. The head of the screw rested in a small round 
 hole on the back of the lock, so placed as to form a secondary 
 key-hole, to which a small key was fitted. There was thus a 
 double system of locking, effected in the following way: when 
 the large key had been applied, and had begun to act on the 
 primary tumblers, the small key was used to operate on the 
 clamp-screw, and thus bind all of the secondary tumblers to¬ 
 gether, ensuring their position at the exact heights or dis¬ 
 tances to which the primary key had caused them to be lifted. 
 The bolt was then free to be shot, and the first series of tum¬ 
 blers reverted to their original position. 
 
 But such an arrangement has obvious inconveniences. 
 Few persons would incur the trouble of using two keys ; 
 and besides this, there were not wanting certain defects in 
 the action and reaction of the several parts ; for if the clamp- 
 screw were to be left unreleased, the first series of tum¬ 
 blers would be upheld by the second series in such a way that 
 the exact impression of the lengths of the several bits of the 
 key could be obtained through the key-hole while the lock was 
 unlocked or the bolt unshot. To remedy one or both of these 
 evils was the next object of Mr. Newell’s attention. He made 
 a series of notches or teeth in each of the secondary tumblers, 
 corresponding in mutual distance with the steps or bits of the 
 key; and opposite these notched edges he placed a dog or 
 lever, with a projecting tooth suitable to fall into the notches 
 when adjusted properly in relation to each other. When the 
 key was used, the primary tumblers were raised in the usual 
 
88 
 
 ON LOCKS. 
 
 way, and acted on the secondary tumblers; these latter were 
 so thrown that the dog-tooth caught in the notches and held 
 them fast, thereby rendering the same service as the clamp- 
 screw and the small key in the former arrangement. No other 
 relative position of the bits of the key could now unlock the 
 lock. 
 
 Still, improvement as it was, this change was not enough; 
 Mr. Newell found that his lock, like all the locks that had pre¬ 
 ceded it, was capable of being picked by a clever practitioner; 
 and candidly admitting the fact, he sought to obtain some new 
 means of security. He tried what a series of complicated 
 wards would do, in aid of the former mechanism ; but the 
 result proved unsatisfactory. His next principle was to pro¬ 
 vide a number of false notches on the abutting parts of the 
 primary and secondary tumblers, with alterations in other parts 
 of the apparatus. The theory now depended upon was this, 
 that if the bolt were subjected to pressure, the tumblers would 
 be held fast by false notches, and could not be raised by 
 any lock-picking instrument. To increase the security, a 
 steel-curtain was so adjusted as to cover, or at least protect, 
 the key-hole. Great anticipations were entertained of this lock, 
 but they were destined to be negatived. A clever American 
 machinist, Mr. Pettit, accepted Messrs. Day and Newell’s chal¬ 
 lenge (500 dollars to any one who could pick this lock); he 
 succeeded in picking the lock, and thus won the prize. 
 
 Once again disappointed, Mr. Newell re-examined the whole 
 affair, and sought for some new principle of secimty that had 
 not before occurred to him. He had found that, modify his 
 lock how he might, the sharp-eyed and neat-fingered mecha¬ 
 nician could still explore the interior of the lock in such a 
 way as to find out the relative positions of the tumblers, and 
 thus adapt their means to the desired end. How, therefore, to 
 shut out this exploration altogether became the problem; how 
 to make a lock, the works of which should be parautoptic —to 
 coin a word from the Greek, which should signify concealed 
 from view. The result of his labours was the production of 
 
AMERICAN LOCKS. 
 
 89 
 
 the American bank-lock now known by that name. The de¬ 
 tails of this lock may now conveniently be given. 
 
 In fig. 40 the lock is represented in its unlocked state, with 
 the cover or top-plate removed; the auxiliary tumbler and the 
 detector-plate are also removed. In fig. 41 it is represented as 
 
 fig. 40. The American Parautoptic lock ; bolt unshot. 
 
 locked, with the cover and the detector-plate also removed, and 
 the auxiliary tumbler in its place. In these two figures, the 
 same letters of reference apply to the same parts, unless other¬ 
 wise stated, bb is the bolt ; t 1 are the first series of mov¬ 
 able slides or tumblers; s shews the tumbler-springs; t 2 the 
 secondary series of tumblers; and t the third or intermediate 
 series these latter coming between the first and secondary 
 series; pp are the separating plates between the several mem¬ 
 bers of the first series of tumblers; s 1 are the springs for lifting 
 the intermediate tumblers. On each of the secondary tumblers 
 t 2 is a senes of notches, corresponding in mutual distance with 
 the difference in the lengths of the movable bits of the key. 
 It thence happens that, when the key is turned in the lock to 
 lock it, each bit raises its proper tumbler, so that some one 
 of these notches shall present itself in front of the tooth t in 
 
90 
 
 ON LOCKS. 
 
 the dog or lever L l. When the bolt b is projected by the ac¬ 
 tion of the key, it carries with it the secondary tumblers t 2 , and 
 presses the tooth t into the notches; in so doing, it withdraws 
 the tongues d from between the jaws jj of the intermediate 
 tumblers t 3 , and allows the first and intermediate tumblers to 
 fall to their original position. By the same movement, the 
 secondary tumblers t‘ become held in the position given to 
 them by the key, by means of the tooth t being pressed into 
 the several notches, as shewn in the closed state of the lock 
 (fig. 41). Now let us see what results if any attempt be made 
 
 fig. 41. The same with the bolt shot. 
 
 to open the lock with any arrangement of key but that by 
 which it has been locked. In such case, the tongues d will 
 abut against the jaws jj, preventing the bolt from being with¬ 
 drawn ; and should an attempt be made to ascertain which 
 tumbler binds and requires to be moved, the intermediate tum¬ 
 bler t 3 (which receives the pressure), being behind the iron 
 Avail 11 , which is fixed completely across the lock, prevents the 
 possibility of its being reached through the key-hole; and the 
 first tumblers t are quite detached at the time, thereby making 
 
AMERICAN LOCKS. 
 
 91 
 
 it impossible to ascertain tlie position of the parts in the inner 
 chamber behind the wall 11. k is the drill-pin, on which the 
 key fits; and c is a revolving ring or curtain, which turns 
 round with the key, and prevents the possibility of inspecting 
 the interior of the lock through the key-hole. Should, however, 
 this ring be turned to bring the opening upwards, a detector-plate 
 
 fig. 42. The detector plate of the Parautoptie look. 
 
 D, fig. 42, is immediately carried over the key-hole by the motion 
 of a pin p x upon the auxiliary tumbler t 4 , which is lifted by 
 the revolution of the ring c, thereby effectually closing the key¬ 
 hole. As an additional protection, the bolt is held from being 
 unlocked by the stud or stump s bearing against the detector- 
 plate; and, moreover, the lever 11 holds the bolt, when locked, 
 until it is released by the tail of the detector-plate pressing the 
 pin p 1 ; l' is a lever which holds the bolt on the upper side, 
 when locked, until it is lifted by the tumblers acting on the 
 pin p ; x are separating-plates between the intefmediate tum¬ 
 blers t 3 ; uu l are the studs for preserving the parallel motion 
 of the different tumblers. 
 
 k'ig- 4 o represents the key in two different forms, or with 
 the bits differently arranged. Either form will lock the lock, 
 but the other will not then unlock it. The end of the key is 
 represented in fig. 44, shewing the screw which fixes the bits 
 
92 
 
 ON LOCKS. 
 
 fig. 43. Key of the Parautoptic lock. 
 
 fig. 44. End view of the key. 
 
 in their places. The bits for a six-bitted key are shewn 
 separately in fig. 45. 
 
 fig. 45. Separate bits of the key. 
 
 In 1847 the parautoptic lock was exhibited at Vienna be¬ 
 fore the National Mechanics’Institute of Lower Austria; and 
 towards the close of the year Mr. Belmont, consul-general of 
 Austria at New York, placed in the hands of Messrs. Day and 
 Newell a letter, a diploma, and a gold medal, forwarded by the 
 Institute. The letter was from the president of the Institute to 
 Mr. Newell, and was couched in the following terms: 
 
 “ The Institute of Lower Austria, at its last monthly session, 
 has passed the unanimous resolution to award to you its gold 
 medal, as an acknowledgment of the uncommon superiority of 
 the combination-lock of your invention; and this resolution was 
 ratified in its general convention held on the 10th instant. 
 
 “ Whilst I, as president of this Institute, rejoice in seeing 
 the services which by this invention you have rendered to the 
 locksmith’s art thus appreciated and recognised, I transmit to 
 you, enclosed, the said medal, together with the documents re- 
 
AMERICAN LOCKS. 
 
 93 
 
 lating to it; at the same time availing myself of this oppor¬ 
 tunity to assure you of my esteem. 
 
 “ COLLOEEDO MaNNSFELD. 
 
 “ Vienna, May 31st, 1847.” * 
 
 The diploma and the medal were similar to other honorary 
 distinctions of the same class, and need not be described here; 
 but the report of the special committee may be given, as it ex¬ 
 presses the opinions of the Viennese machinists on the relative 
 principles by which safety is sought to be obtained in different 
 kinds of locks. 
 
 REPORT 
 
 Of a Special Committee on the new Parautoptic Permutation Loch of the 
 American Newell, made known to the Lower Austrian Institute ly the 
 Councillor, Professor Reuter, and on the motions relating to it made ly 
 the same and accepted ly the Institute. Presented at the monthly meeting, 
 April 6th, 1847, ly Mr. Paul Sprenger, Aulic Councillor on Pullic 
 Works, Ac. Ac. 
 
 Gentlemen At our last monthly meeting, Mr. Reuter, Aulic Coun¬ 
 cillor and Secretary of the Institute, directed your attention to a newly 
 Invented lock of Mr. Newell, of North America, which was represented as 
 excelling all other changeable combinationdocks hitherto known, and as 
 being without a rival. 
 
 The Special Committee which was intrusted with the examination of 
 this lock, and of the motions made by the said Secretary, and accepted by 
 the Institute, has conferred on me the honour of making you acquainted 
 with the results of its investigations. 
 
 The attention of your committee was chiefly occupied with the three 
 questions proposed by the said Aulic Councillor in relation to the lock in 
 question : 
 
 First: Whether the idea of Mr. Newell was of any practical value for 
 already existing and still-to*be-invented combination-locks ; 
 
 Secondly: Whether the idea was of sufficient importance to be pub¬ 
 lished and minutely described in the transactions of the said Institute ; and 
 Thirdly : Whether the merits of the inventor were of sufficient import¬ 
 ance to entitle him to a distinction from the said Institute. 
 
 The deliberations on the first question, viz. the newness of the idea, and 
 of its practical value, would of necessity enlist the particular attention of 
 your committee, especially since by far the greater number of its members 
 are by their avocation called upon to be interested in the execution of all 
 kinds of locks. 
 
 It is therefore the unanimous opinion of your committee, that the idea 
 
94 
 
 ON LOCKS. 
 
 of the American Parautoptic Combination-Lock is entirely new and without 
 example. 
 
 The combination-locks with keys have, with few exceptions, such an 
 arrangement that a determinate number of movable parts (the so-called 
 combination-parts) must by the turning of the key be raised or lifted into 
 a certain position, if it is desired to project the bolt, or, what is the same 
 thing, to lock it out; consequently these parts, or, as they are technically 
 termed, tumblers, could not be transposed or changed, from the circum¬ 
 stance that the key-bit was one solid piece, with various steps or notches 
 adapted to the several tumblers, and one impression from it destroyed the 
 security of the lock. 
 
 In order, however, to add more security to such a combination-lock, 
 and to make the key, in case it should be lost, or any counterfeit made from 
 a wax impression, useless for an unlawful opening of the lock, another step 
 was taken : the key-bit was made to consist of several bits or movable parts, 
 in such a manner that the owner of the lock was enabled to change the 
 bits, and to form, as it were, new keys different from the former. But since 
 the bolt of the lock can only be projected whilst the combination parts or 
 tumblers are in a certain position, which position depends upon the order 
 of the bits in the key, it is evident that the owner, when changing the key, 
 must at the same time make a corresponding change in the position of the 
 tumblers in the lock itself, before the lock can be of any use for the newly 
 changed shape of the key, which rendered it troublesome, and impracticable 
 for the purpose designed, from the fact that no positive change could be 
 made in the lock, without taking it from the door, and then taking the 
 tumblers out of the case, to change them in a suitable form for the key. 
 
 This principle of changing the lock is rarely adhered to, as few men 
 understand the machinery of a lock sufficiently to undertake the task ; and 
 this circumstance rendered the lock quite as insecure as the former one 
 described. 
 
 Another step toward the perfection of combination-locks consisted in 
 this, that the key remains unaltered whilst the combination parts of the 
 lock can, before it is locked, be brought into different positions by means of 
 movable plates on the frame of the lock. These plates were arranged by 
 hand to certain figures, and depended on the memory for adjustment at 
 each time the bolt was to be locked out or in, the key operating only on the 
 bolt, to move it back and forth when the plates were set in proper positions 
 for the purpose ; and should the owner forget the arrangement of the 
 plates, after projecting the bolt, his key is of no use to him, and he must 
 resort to the skill of the locksmith to gain access. 
 
 The same case may occur in the far less perfect ring-lock of Reynier, 
 which is operated without keys, and is opened by means of the rings being 
 turned in a particular position ; on these rings are usually stamped letters, 
 which, by introducing some word readily suggested to the memory, thus 
 point out the relative position of the rings. 
 
 But although in case of these ring-locks the owner is enabled to produce 
 
AMERICAN LOCKS. 
 
 95 
 
 a change in the rings in such a manner that the opening of the lock can, as 
 it were, only become possible by rightly arranging the altered position of 
 the letters, still this lock of Reynier’s does not possess that safety and per¬ 
 fection which could have insured it universal application. 
 
 M. CriveUi, formerly professor at Milan, has given a minute description 
 of the imperfection of ring-locks generally, in the annals of the Imperial 
 Royal Polytechnic Institute. 
 
 It is the unanimous conviction of your committee that the American 
 Lock of Newell surpasses, in the ingenuity displayed in its construction, all 
 other locks heretofore known, and more especially in this, that the owner 
 can, with the greatest facility, change at pleasure the interior arrangement 
 of his lock to a new and more complex one, at every moment of his life, 
 simply by altering the arrangement of the bits in the key, and this is ac¬ 
 complished without removing the lock or any part of it from its position on 
 the door. 
 
 Its operation is as follows :—-At the closing or locking of the lock, whilst 
 the bolt is projecting, the movable combination parts assume precisely the 
 position prescribed to them by the key, according to the particular arrange¬ 
 ment of its bits at the time the key is turned. 
 
 The combination parts do not consist in one set of tumblers only, such 
 as are found in all other locks, but there are three distinct sets or compo¬ 
 nent parts fitting into each other. When the holt is projected, it dissolves 
 the mutual connexion of the constituent pieces, and carries along with it 
 such as are designedly attached to it, and which assume the particular 
 positions given them by the key in its revolution. These parts are rendered 
 permanent in their given form by means of a lever adapted for the purpose, 
 while the parts not united with the bolt are pressed down by their springs 
 to their original places. 
 
 If now the bolt is to be returned again, i. e. if the lock is to be unlocked, 
 then the constituent pieces or tumblers which are in the original state must, 
 by means of the key, be again raised into that position in which they were 
 when the lock was closed, as otherwise the constituent parts attached to 
 the holt would not lock in with the former, and the bolt could not be re¬ 
 turned. Nothing, therefore, but the precise key which had locked the lock 
 can effect the object. 
 
 This idea in itself, considered by youi* committee, is as ingenious as it is 
 new, and is accompanied by a perfection in its execution which reflects the 
 highest honour on Mr. Newell, the inventor and manufacturer of the lock. 
 
 The lock is built strong and solid, and the several parts are admirably 
 adapted to the functions which they are designed to perform. The walls 
 of steel or iron which separate the security parts from the tumblers, and 
 the cylinder which revolves with the key, present formidable barriers to all 
 descriptions of pick-locks, and render the lock a most positive and reliable 
 security. The tumblers consist of rolled very smooth steel plates, in which 
 the fire-crust has not been filed away, partly in order that the lock might 
 not need oiling, as all these parts are very smooth, and partly that the 
 
96 
 
 ON LOCKS. 
 
 combination pieces might not easily rust, a thing to which the adhering 
 fire-crust is not favourable. The springs, which by the turning of the key 
 must be raised together with the tumblers, are attached to levers, and 
 press upon the latter at their centre of gravity, in consequence of which all 
 crowding towards either side is prevented, and the key can be turned with 
 facility, in spite of the many combination parts which it has to raise ; and 
 the springs themselves are by their positions so little called into action, ' 
 that their strength can never be impaired by use. 
 
 The lock has also another very complete arrangement in the detector- 
 tumbler, which is attached to the cap or covering of the lock. This tum¬ 
 bler, on turning the key either way, closes the key-hole, and not only pre¬ 
 vents the use of false instruments in the lock, but detects all attempts at 
 mutilating its interior parts. 
 
 This lock is especially useful for locking bank-vaults, magazines, count¬ 
 ing-houses, and iron-safes, in which valuable effects, money, or goods are 
 to be deposited for safe keeping. When it is considered that the bits of 
 the key belonging to this lock can be transferred into every possible form 
 within its limits, and since the construction of the lock admits of every 
 combination of the slides resulting from the changes of the key, therefore 
 the lock in question is, in every respect, deserving of the appellation given 
 to it by the Secretary of the Institute, namely, the Universal Combination 
 Lock; and justly so, when we consider that the ten bits attached to the 
 key admit of three millions of permutations, and upward ; consequently 
 forming that number of different kinds of keys and locks. 
 
 If we consider further, that we need not be limited to the given bit, but 
 that others can be applied, differing in their dimensions from the former ; 
 and again, if we consider that from every system arising from a difference 
 in their relative dimensions, a large number of new keys differing from each 
 other will result, and that this can be effected in a space scarcely occupying 
 a square inch,—then we cannot refrain from confessing that the human 
 mind, within this small space, has shewn itself to be infinitely great. 
 
 After this preliminary and general exposition, your committee can 
 answer the three questions propounded to them the more briefly, as the 
 locks heretofore known have all been noticed. 
 
 To question first.—On the practical value of the invention of Mr. Newell, 
 your committee were unanimous and positive that the principle on which it 
 is based should be preserved. 
 
 To question second.—For this reason the committee deemed it desirable 
 that a drawing and description of the American lock in question should be 
 published in the Transactions of the Institute of Lower Austria. 
 
 To question third.—With regard to the claims of the inventor, Mr. 
 Newell, to an honorary distinction from the Institute of Lower Austria, the 
 committee recommend that he be presented with a Diploma of honourable 
 mention and a Gold Medal. 
 
 The members of your committee, consisting mostly of fellow-tradesmen 
 of Mr. Newell, experience great satisfaction in the fact that it has fallen to 
 
AMERICAN LOCKS. 
 
 97 
 
 their lot to vote to their colleague on the other side of the ocean an acknow¬ 
 ledgment of his successful ingenuity, and they close the Report with the 
 request that the Institute will transmit to Mr. Newell of New York, in 
 North America, the Diploma and Gold Medal, together with a copy of this 
 Report, according to the motion of the Aulic Councillor and Professor 
 Reuter. 
 
 [An exact copy of the original Report as preserved in the archives of the 
 
 National Mechanics’ Institute of Lower Austria.] 
 
 DR. SCHWARTZ, 
 Assistant Secretary of the Institute. 
 
 There are other circumstances connected with the Ameri¬ 
 can bank-lock, in relation to events both in the United States 
 and in England, to which attention will be directed in a sub¬ 
 sequent chapter. 
 
 The English patent for Messrs. Day and Newell’s lock, 
 dated April 15, 1851, runs as follows: “The object of the 
 present improvements is the constructing of locks in such 
 manner that the interior arrangements, or the combination of 
 the internal movable parts, may be changed at pleasure accord¬ 
 ing to the form given to, or change made in, the key, without 
 the necessity of arranging the movable parts of the lock by 
 hand, or removing the lock or any part thereof from the door. 
 In locks constructed on this plan the key may be altered at 
 pleasure ; and the act of locking, or throwing out the bolt ? of 
 the lock, produces the particular arrangement of the internal 
 parts which corresponds to that of the key for the time being. 
 While the same is locked, this form is retained until the lock 
 is unlocked or the bolt withdrawn, upon which the internal 
 movable parts return to their original position with reference 
 to each other; but these parts cannot be made to assume or be 
 brought back to their original position, except by a key of the 
 precise form and dimensions as the key by which they were 
 made to assume such arrangement in the act of locking. The 
 key is changeable at pleasure, and the lock receives a special 
 form in the act of locking according to the key employed, and 
 retains that form until in the act of unlocking by the same 
 key it resumes its original or unlocked state. The lock is 
 
 F 
 
98 
 
 ON LOCKS. 
 
 again changeable at pleasure, simply by altering the arrange¬ 
 ment of the movable bits .of the key; and the key may be 
 changed to any one of the forms within the number of permu¬ 
 tations of which the parts are susceptible.” 
 
 The “ claims” put forth under this patent are the fol¬ 
 lowing :— 
 
 “ 1. The constructing, by means of a first and secondary 
 series of slides or tumblers, of a changeable lock, in which the 
 particular form or arrangement of parts of the lock, imparted 
 by the key to the first and secondary series of slides or tum¬ 
 blers, is retained by a cramp-plate. 
 
 “ 2. The constructing, by means of a first and secondary 
 series of slides or tumblers, of a changeable lock, in which 
 the peculiar form or arrangement of parts of the lock, im¬ 
 parted by the key, is retained by means of a tooth or teeth, 
 and notches on the secondary series of slides or tumblers. 
 
 “ 3. The application to locks of a third or intermediate 
 series of slides or tumblers. 
 
 “ 4. The application of a dog with a pin over-lapping the 
 slide or tumblers, for the purpose of holding-in the bolt when 
 the lock is locked or unlocked. 
 
 “ 5. The application of a dog operated on by the cap or 
 detector-tumbler for holding the bolt. 
 
 “ 6. The application of a dog for the purpose of holding 
 the internal slide or tumbler. 
 
 “ 7. The application to locks of curtains or rings, turn¬ 
 ing and working eccentrically to the motion of the key, for 
 preventing access to the internal parts of the lock. 
 
 “ 8. The application to locks of a safety-plug or yielding- 
 plate, at the back of the chamber formed by such eccentric re¬ 
 volving curtain or ring. 
 
 “ 9. The application to locks of a strong metallic wall or 
 plate, for the purpose of separating the safety and other parts 
 of the lock from each other, and preventing access to such 
 parts by means of the key-hole. 
 
 “ 10. The application to locks of a cap or detective turn- 
 
AMERICAN LOCKS. 
 
 99 
 
 bier, for the purpose of closing the key-hole as the key is 
 turned. 
 
 “11. The constructing a key by a combination of bits or 
 movable pieces, with tongues fitted into a groove and held by 
 a screw. 
 
 “12. The constructing a key having a groove in its shank 
 to receive the detector tumbler.” 
 
 When the American locks became known in England, Mr. 
 Hobbs undertook the superintendence of their manufacture, 
 and their introduction into the commercial world. Such a 
 lock as that just described must necessarily be a complex 
 piece of mechanism; it is intended for use in the doors of re¬ 
 ceptacles containing property of great value; and the aim has 
 been to baffle all the methods at present known of picking 
 locks, by a combination of mechanism necessarily elaborate. 
 Such a lock must of necessity be costly; but in order to supply 
 the demand for a small lock at moderate price, Mr. Hobbs has 
 introduced what he calls a protector lock. This is a modifica¬ 
 tion of the ordinary six-tumbler lock. It bears an affinity to 
 the lock of Messrs. Day and Newell, inasmuch as it is an 
 attempt to introduce the same principle of security against 
 picking, while avoiding the complexity of the changeable lock. 
 The distinction which Mr. Hobbs has made between secure 
 and insecure locks will be understood from the following 
 proposition, viz. “ that whenever the parts of a lock which 
 come in contact with the key are so affected by any pressure 
 applied to the bolt, or to that portion of the lock by which 
 the bolt is withdrawn, as to indicate the points of resistance to 
 the withdrawal of the bolt, such a lock can be picked.” 
 Fig. 47 exhibits the internal mechanism of this new patent 
 lock. It contains the usual contrivances of tumblers and 
 springs, with a key cut into steps to suit the 
 | different heights to which the tumblers must be 
 1 raised. The key is shewn separately in fig. 48. 
 
 But there is a small additional piece of me- fig. 46. Mov- 
 chanism, in which the tumbler stump shewn at s in able stum P* 
 
100 
 
 ON LOCKS. 
 
 fig. 47. Hobbs’s Protector Lock. 
 
 figs. 46 and 47 is attached; which piece is intended to work under 
 or behind the bolt of the lock. In fig. 47, b is the bolt; tt is 
 the front or foremost of the range of six tumblers, 
 each of which has the usual slot and notches. In 
 other tumbler-locks the stump or stud which 
 moves along these slots is riveted to the bolt, in 
 such manner that, if any pressure be applied in an 
 attempt to withdraw the bolt, the stump becomes 
 pressed against the edges of the tumblers, and 
 bites or binds against them. How far their biting 
 facilitates the picking of a lock will be shewn fur¬ 
 ther on; but it will suffice here to say, that the 
 movable action given to the stump in the Hobbs 
 lock transfers the pressure to another quarter. 
 The stump s is riveted to a peculiarly-shaped 
 piece of metal lip (fig. 46), the hole in the centre of 
 which fits upon a centre or pin in a recess formed at the back 
 of the bolt; the piece moves easily on its centre, but is pre¬ 
 vented from so doing spontaneously by a small binding spring. 
 The mode in which this small movable piece takes part in the 
 action of the lock is as follows: when the proper key is applied 
 in the usual way, the tumblers are all raised to the proper heights 
 for allowing the stump to pass horizontally through the gating; 
 but should there be an attempt made, either by a false key or by 
 any other instrument, to withdraw the bolt before the tumblers 
 are properly raised, the stump becomes an obstacle. Meeting 
 
 fig. 48. The 
 key. 
 
AMERICAN LOCKS. 
 
 101 
 
 with an obstruction to its passage, the stump turns the piece to 
 which it is attached on its centre, and moves the arm of the 
 piece p so that it shall come into contact with a stud riveted 
 into the case of the lock; and in this position there is a firm 
 resistance against the withdrawal of the bolt. The tumblers 
 are at the same moment released from the pressure of the 
 stump. There is a dog or lever d, which catches into the top 
 of the bolt, and thereby serves as an additional security 
 against its being forced back. At 1c is the drill-pin on which 
 the pipe of the key works; and r is a metal piece on which 
 the tumblers rest when the key is not operating upon them. 
 
 Another lock, patented by Mr. Hobbs in 1852, has for its 
 object the absolute closing of the key-hole during the process 
 of locking. The key does not work or turn on its own centre, 
 but occupies a small cell or chamber in a revolving cylinder, 
 which is turned by a fixed handle. The bit of the movable 
 key is entirely separable from the shaft or stem, into which 
 it is screwed, and may be detached by turning round a 
 small milled headed thumb-screw. The key is placed in 
 the key-hole in the usual way, but it cannot turn; its cir¬ 
 cular movement round the stem as an axis is prevented by 
 the internal mechanism of the lock; it is left in the key-hole, 
 and the stem is detached from it by unscrewing. By turning 
 the handle, the key-bit, which is left in the chamber of the 
 cylinder, is brought into contact with the works of the lock, so 
 as to shoot and withdraw the bolt. This revolution may 
 take place whether the bit of the movable key occupy its 
 little cell in the plate or not; only with this difference—that 
 if the bit be not in the lock, the plate revolves without acting 
 upon any of the tumblers; but if the bit be in its place, it 
 raises the tumblers in the proper way for shooting or with¬ 
 drawing the bolt. It will be understood that there is only one 
 key-hole, namely, that through which the divisible key is in¬ 
 serted ; the other handle or fixed key working through a hole 
 in the cover of the lock only just large enough to receive it, 
 and not being removable from the lock. As soon as the plate 
 
102 
 
 ON LOCKS. 
 
 turns round so far as to enable the key-bit to act upon the 
 tumblers, the key-hole becomes entirely closed by the plate 
 itself, so that the actual locking is effected at the very time 
 when all access to the interior through the key-hole is cut off. 
 When the bolt has been shot, the plate comes round to its ori¬ 
 ginal position, it uncovers the key-hole, and exhibits the key- 
 bit occupying the little cell into which it had been dropped; 
 the stem is then to be screwed into the bit, and the latter 
 withdrawn. It is one consequence of this arrangement, that 
 the key has to be screwed and unscrewed when used; but 
 through this arrangement the key-hole becomes a sealed book 
 to one Avho has not the right key. Nothing can be moved, 
 provided the bit and stem of the key be both left in; but by 
 leaving in the lock the former without the latter, the plate can 
 rotate, the tumblers can be lifted, and the bolt can be shot. 
 
 CHAPTER Vm. 
 
 THE LOCK CONTROVERSY : PREVIOUS TO THE DATE OF THE GREAT 
 EXHIBITION. 
 
 It must be evident, even on a cursory glance at the past his¬ 
 tory of the lock-manufacture, that the prime motive for the 
 introduction of novelties and improvements in construction is 
 the desirability of producing a lock which no one can open 
 without the proper key. From the earliest and simplest lock, 
 down to the latest and most complex, this object has been 
 constantly held in view ; and every clear proof or evidence 
 that this object has not been attained has led to the invention 
 of some new contrivance. It has been a succession of struggles 
 —to attain security—-to shew that this security has not been 
 attained—to make a further and more ingenious attempt—to 
 detect the weak point in this renewed attempt—and so on. 
 We need not repeat here, what was stated in an early chapter, 
 
THE LOCK CONTROVERSY. 
 
 103 
 
 that benefit must ultimately result from a candid discussion of 
 this question. When M. Reaumur proposed to explain how 
 the locks of his day could be picked or opened without the 
 true key, his object was to shew to persons who were not lock¬ 
 smiths how far they could depend upon the principle of security 
 offered by locks. But before proceeding on his inquiry, the 
 illustrious naturalist asks, “ Ne craindra-t-on pas que nous ne 
 donnions en meme terns des lemons aux voleurs ?” And he re¬ 
 plies, “ II n’y a pas grande apparence qu’ils viennent les cher- 
 cher ici, et qu’ils en aient besoin ; ils sont plus grands maitres 
 que nous dans l’art d’ouvrir les portes. Apprenons done l’art 
 d’ouvrir les portes fermees, afin d’apprendre celui de les fermer 
 d’une maniere qui ne laisse rien ou qui laisse peu a craindre.”* 
 
 Before treating of lock controversies and lock violability in 
 England, it will be desirable first to refer to America, where 
 this subject attracted much attention some years earlier than 
 the Great Exhibition—an Exhibition which will always be 
 associated in a remarkable manner with the history of locks. 
 
 Soon after the inventions by Dr. Andrews and Mr. Newell, 
 in 1841 (described in a former chapter), the rivalry between 
 the two locks ran high ; each lock being ‘ unpickable,’ accord¬ 
 ing to the estimate of its inventor. Mr. Newell thought the 
 best mode of shewing the superiority of his own lock would 
 be by picking that of his competitor ; and after several trials, 
 he succeeded in bringing into practical application that system 
 of picking which we may designate the mechanical , as contra¬ 
 distinguished from the arithmetical. Mr. Newell not only picked 
 Dr. Andrews’ lock, but he wound up the enterprise by picking 
 his own! He was probably the first person who honestly con¬ 
 fessed to having picked his own unpickable lock. This dis- 
 
 * “ But is there not this danger, that at the same time we shall be 
 giving lessons to the thieves ? It is not very probable that they will seek 
 instruction of us, or that they have any need of it; they are greater masters 
 in the art of opening doors than we can pretend to be. Let us then learn the 
 art of opening locked doors, in order that we may acquire that of securing 
 them in such a way as to leave little or nothing to be feared on account of 
 their security.” 
 
104 
 
 ON LOCKS. 
 
 covery led Mr. Newell, as has been noticed in a former page, 
 to the invention of the triple-action or parautoptic lock. 
 
 The mechanical principle, as applied to the picking of a 
 tumbler lock, is nearly the same whatever form of construction 
 be made the medium of experiment. When a pressure is ap¬ 
 plied to the bolt sufficient to unlock it if the tumbler-obstruc¬ 
 tions were removed, the edges of the tumbler bite or bind 
 against the stump of the bolt, so as not to move up and down 
 with such facility as under ordinary circumstances. By care¬ 
 fully trying with a small instrument each tumbler, and moving 
 it until the bite ceases, the gating of that particular tumbler 
 may be brought to the exact position for allowing the stump 
 of the bolt to pass through it. (See page 118.) 
 
 This violability is observable in the tumbler-locks under 
 very varied forms of construction. Mr. Newell, after he had 
 picked his own lock, devised a series of complicated wards, to 
 add to the difficulty of reaching the tumblers ; but he could 
 not thereby ged rid of the importance of this fact, that wher¬ 
 ever a key can go, instruments of a suitable size and form 
 could follow : his wards did not render his lock inviolable. 
 His next contrivance was to notch the abutting parts of the 
 primary and secondary tumblers, or the face of the stump and 
 the ends of the tumblers; but this failed also. Mr. II. C. Jones, 
 of Newark, N. J., added to all this a revolving pipe and 
 curtain, to close as much of the key-hole as possible. But 
 so far were all these precautions from being successful, that a 
 lock provided with all these appendages, and affixed to the 
 door of the United States Treasury at Washington, was picked. 
 The makers of locks have, each one for himself, contended 
 against such difficulties as Avere known to them at the time of 
 inventing their locks ; and, mortifying as failure may be, it 
 would be cmvardly to yield up the enterprise Avlienever any 
 new difficulty presented itself. Difficulties, in locks as in other 
 matters, are made to be conquered. 
 
 To shew how numerous are the sources of insecurity 
 Avhich have to be guarded against, to meet the skill often 
 
THE LOCK CONTROVERSY. 
 
 105 
 
 brought to bear upon this lock, we may adduce the reasons 
 which led Mr. Newell to apply a curtain to the key-hole of his 
 lock. Supposing the interior arrangement of the triple set of 
 tumblers, and the metallic shielding wall, to be perfect, still, 
 if the first set of tumblers can be seen through the key-hole, the 
 following plan may be put in operation. The under-side of 
 the tumblers may be smoked, by inserting a flame through 
 the key-hole; and the key will then leave a distinct mark 
 upon each tumbler the next time it is used, shewing where it 
 began to touch each tumbler in lifting it. This may be seen 
 by inserting a small mirror hinged into the lock through the 
 key-hole. There may even be an electric light used from a 
 small portable battery, to illumine the interior of the lock. 
 By these and other means the exact length of each bit of the 
 key may be determined; and from these data a false key may 
 be made. It is to prevent this inspection of the works, or any 
 other examination of an analogous kind, that the revolving 
 curtain was applied; but, as stated in the last paragraph, even 
 this did not suffice : ingenuity devised a mode of baffling the 
 contrivance of curtains as well as that of the wards and false 
 notches in the tumblers. 
 
 When the parautoptic lock was completed, it was keenly 
 criticised in America, owing to the long discussions respecting 
 the merits of previous locks. In a matter of this kind, where 
 a commercial motive would lead bankers and companies to 
 apply a very severe test to the security of locks and similar 
 J fastenings to strong-rooms and receptacles, any experiments 
 made with their sanction became important. Mere letters or 
 
 I certificates emanating from individuals, expressive of opinions 
 concerning a particular lock, would be out of place in a volume 
 relating to locks generally ; but it is quite within the limits of 
 i the subject, and has indeed become part of the history of locks, 
 
 J to notice experiments and attempts of a more public character. 
 We may therefore introduce a few paragraphs of this description, 
 relating to the career of the American lock in America itself. 
 The principal bankers at Boston (U. S.) held a meeting to 
 e 2 
 
106 
 
 ON LOCKS. 
 
 take into consideration measures for testing the security of 
 bank locks. Consequent on this meeting, Messrs. Day and 
 Newell deposited live hundred dollars with the cashier of the 
 State Bank at Boston, to be by him paid to any one who could 
 pick the parautoptic lock : the trial was to be conducted under 
 the auspices of the bank. One of the locks was brought to 
 the bank, and was minutely examined by two machinists on 
 two afternoons, after which it was secured to an iron chest, 
 and locked by a committee appointed by the bank. The key 
 was to remain in the hands of the committee during the trial; 
 and it was to be used at their discretion, in unlocking and lock¬ 
 ing the door, •without the knowledge of either of the other par¬ 
 ties— provided that in so doing no alteration was made in the 
 combination-parts of the key. Ten days were allowed to the 
 operators for the examination and the trial ; if they succeeded 
 they were to have five hundred dollars ; but if they injured 
 the lock they agreed to forfeit two hundred, as a purchase 
 price. At the end of the period the lock remained unopened 
 and uninjured ; and the two deposited sums were accordingly 
 returned to the respective parties. 
 
 Messrs. Page and Bacon, of St. Louis, had a strong-room 
 lock made by one of the chief locksmiths of that city. To 
 test its security, the proprietors requested Mr. Hobbs to at¬ 
 tempt to pick it; he did so, and succeeded. Whereupon the 
 proprietors, having purchased one of the parautoptic locks, 
 deemed it no more than fair play to subject this lock to a 
 similar ordeal, an additional zest being given by a reward of 
 five hundred dollars offered by Day and Newell to the success¬ 
 ful picker. The maker of the former lock accepted the chal¬ 
 lenge ; he was allowed to examine the new lock piecemeal, 
 and was then allowed thirty days for his operations in picking. 
 He failed in the enterprise. Of course, in this, as in all similar 
 cases, the operator had not access to the true key. 
 
 It follows from the nature of this lock, as noticed in a 
 former chapter, that when the bolt has been shot, if the bits 
 of the key be re-arranged in any other form, the lock becomes 
 
THE LOCK CONTROVERSY. 
 
 107 
 
 to all intents and purposes a new lock, so far as that key is 
 concerned, and cannot be unlocked unless the key revert to 
 its original arrangement. To test this principle, a box with 
 a parautoptic lock was placed in the room of the American 
 Institute in 1845 ; it was locked; the bits of the key (12 in 
 number) were then re-arranged, and the key was placed in the 
 hands of any one who chose to try to open the lock — with 
 the offer of a reward of five hundred dollars in the event 
 of the lock being opened. Here, instead of the operator being 
 called upon to devise new pick-lock implements, he had the 
 actual key placed in his hands, modified however in such a 
 way that, though the modifier could restore the original ar¬ 
 rangement (provided he had kept some kind of record), the 
 operator had numerous chances against his success. The lock 
 remained unopened notwithstanding this challenge. 
 
 We shall have occasion to shew presently, that if the num¬ 
 ber of tumblers (and consequently the number of bits in the 
 key) be small—not exceeding six, for instance—the possession 
 of the ti'ue key gives any one the power of opening the lock, 
 provided he has time and patience to go through a few hundred 
 changes of the bits of the key; for, as some one arrangement 
 must have been that by which the lock was locked, it must 
 again occur if the user takes care to make all the arrange¬ 
 ments in turn, and tries the lock after each. Whether this 
 constitutes picking a lock, each lock-owner will decide for 
 himself. All that it is at present meant to state is, that without 
 access to the true key, the parautoptic lock has not hitherto 
 been opened; and that with the true but altered key the pro¬ 
 cess of opening is possible, but is slow and tedious. 
 
 In 1846 the American Institute appointed a committee to 
 examine into the merits of the parautoptic lock. On the 18th 
 of September in that year the Committee made their report, 
 signed by Professor Renwiok and Mr. T. W, Harvey, as 
 follows:— 
 
 “ The Committee of the American Institute, to whom was 
 referred the examination of Newell’s Parautoptic Bank 
 
108 
 
 ON LOCKS 
 
 Lock, report that they have given the subject referred to 
 them a careful and attentive examination, and have received 
 full and complete explanations from the inventor. They have 
 remarked in the lock a number of important ad vantages, and, 
 in particular, very great improvements upon the permutation- 
 lock formerly submitted by him to the American Institute. 
 Thus, while it retains the advantages of the permutation prin¬ 
 ciple, combined with the property that the act of locking sets 
 the slides to the particular arrangement of the bits in the ske¬ 
 leton key, the parts thus set are completely screened from ob¬ 
 servation, from being reached by false instruments, or from 
 being injured by any violence not sufficient to break the 
 lock to pieces. 
 
 “ Having in the course of their inquiries examined the dif¬ 
 ferent existing modes in which locks may be picked, forced, or 
 opened by false keys, the Committee have come to the conclu¬ 
 sion that the parautoptic lock cannot be opened by any of the 
 methods now practised, unless by a person in possession of the 
 key by which it was locked, in the exact form of combination 
 in which it was used for the purpose, or in the almost impos¬ 
 sible case of the bits being adjusted to the skeleton key by 
 accident in that very form. As the chances of such accidental 
 combination range according to the number of movable bits, 
 from several thousands to several millions to one, the Com¬ 
 mittee do not conceive that so small a chance of success would 
 ever lead to an attempt to profit by it. 
 
 “ In conclusion, the Committee feel warranted in express¬ 
 ing the opinion, that unless methods hitherto unknown or 
 imagined should be contrived for the specific object, the lock 
 in question may be considered as affording entire and abso¬ 
 lute security.” 
 
 The latest form which Messrs. Day and Newell have given 
 to their challenge, after the experience of the last few years, 
 is the following: 
 
 “ First, a Committee of five gentlemen shall be appointed 
 in the following manner: viz. two by the parties proposing to 
 
THE LOCK CONTROVERSY. 
 
 109 
 
 operate, and two by ourselves; and by tbe four thus appointed 
 a fifth shall be selected. 
 
 “ In the hands of this Committee shall be placed Two 
 Thousand Dollars, as a reward to the operator if successful in 
 picking the lock by fair means. 
 
 “ We will place upon the inside of an iron door one of our 
 best bank locks. The operator shall then have the privilege 
 of taking the lock from the door, and have it in his possession 
 for examination; it shall then be returned to the Committee 
 for our inspection, so that we may be assured that it has not 
 been mutilated or injured. The operator shall then, in the 
 presence of ourselves and the Committee, place the lock upon 
 the door in its original position; after which the Committee 
 shall place upon it their seals, so that it cannot be removed 
 or altered without their knowledge. The lock being thus 
 secured to the door, we shall then be allowed to lock it up 
 ourselves, upon any change of which it is susceptible. 
 
 “ The time for operation to continue thirty days; and if at 
 the end of that time he shall consider that he has made any 
 progress towards picking the said lock, he shall have thirty 
 days more in which to continue operations.” 
 
 The Austrian report concerning the American lock was 
 given in a former page, to which we may here refer; and then 
 direct attention to England, and to the discussions which have 
 lately been carried on respecting the safety of locks. 
 
 It is of course natural that each inventor of a new lock 
 should, while describing the product of his ingenuity, point 
 out what he conceives to be the imperfections of locks which 
 have preceded: use has sanctioned the custom not only with 
 regard to locks, but also in other important matters. Hence 
 
 the last seventy years. We have seen how freely and justly the 
 late Mr. Bramah criticised all the locks that preceded his own; 
 and he was certainly not the man to shrink from criticism in 
 his own case. Twenty years ago the Bramah lock was itself 
 made the subject of criticism. 
 
110 
 
 ON LOCK?. 
 
 Mr. Ainger, in his lecture on the subject delivered at the 
 Boyal Institution, London, and afterwards in his article “Lock” 
 in the Encyclopaedia Britannica, thus narrates the circum¬ 
 stances which led to the adoption of the false notches in the 
 Bramah lock as a means of security: “At length (after the 
 original lock had acquired much celebrity,) an advertisement 
 appeared in the public papers, requesting those who had lost 
 keys of Bramah’s locks, not, as had hitherto been done, to 
 break open their doors or drawers, but to apply to the adver¬ 
 tiser, who would undertake to save this destructive process by 
 picking. And it appeared that an individual of great dex¬ 
 terity could perform this operation almost with certainty. 
 The effect of this discovery on the demand for the locks may 
 easily be imagined; but the effect it had in stimulating inge¬ 
 nuity to provide a remedy is one of the best illustrations of 
 the proverb, that necessity is the mother of invention. Within 
 a few days or weeks, Mr. Bussell, who was at that time em¬ 
 ployed in Mr. Bramah’s establishment, devised an alteration 
 which at once, and without any expense, entirely overcame the 
 difficulty, and converted the lock into one of perfect security. 
 This contrivance is the most simple and extraordinary that 
 ever effected so important an object; but before we describe 
 it, we will endeavour to explain what has been called the ten¬ 
 tative process of lock-picking, and which had been so success¬ 
 fully applied to Bramah’s locks.” 
 
 Mr. Ainger illustrates the subject by an engraving—not of 
 an actual lock, but of an hypothetical arrangement of bolts 
 and notches; and he then makes his reasoning apply to the 
 actual process adopted by the picker of the real lock. “ A 
 tendency to revolve was given with some force to the barrel; 
 then, by means of a pair of small forceps, the tumblers (sliders) 
 were tried, and it was ascertained which one was most de¬ 
 tained by the pressure against the locking-plate. That which 
 offered most resistance was gradually depressed till its notch 
 was felt to hang itself upon the locking-plate; and so on till the 
 whole were depressed in succession, exactly as they would 
 
THE LOCK CONTKOVERSY. 
 
 Ill 
 
 have been depressed simultaneously by the hey.” Mr. Ainger 
 then describes the contrivance which, in his judgment, seemed 
 to render any further attempts to pick the Bramah lock hope¬ 
 less. This consisted in cutting false notches in the sliders; so 
 as to render it impossible for the picker to tell when he has 
 brought a notch to the plane of the locking-plate, whether it 
 is a true notch, or one of shallower depth, unfitted to admit 
 the movement of the plate.” 
 
 This is a very interesting statement, for it shews that the 
 mechanical or tentative method of opening was known in 
 England long ago, although very little attention has been since 
 paid to it. In a complex Bramah lock, and in locks on the com¬ 
 bination principle, the difficulty of picking is almost insuper¬ 
 able, so long as what may be termed the arithmetical method 
 is adopted. It is perfectly true, as has been so often stated, 
 that the varied combinations in the arrangement of the slides 
 amount to millions and even billions, when the slides are in 
 any degree numerous; and if a person attempt to pick the 
 lock by ringing the changes on all these combinations, it 
 would very likely require the lives of a dozen Methuselahs to 
 bring the enterprise to an end. But by the mechanical me¬ 
 thod, sketched so clearly by Mr. Ainger, the exploit puts on a 
 different aspect. The experimenter passes through the key¬ 
 hole an instrument so arranged as to give a tendency in the 
 bolt to withdraw in the wished-for direction; and a pressure 
 produced in the slides by this tendency gives information con¬ 
 cerning the state of the slides; and then comes the tentative 
 process on the slides themselves. Mr. Ainger was quite right 
 in describing the false notches as an admirable addition to the 
 safety of the Bramah lock; but he was not correct in stating 
 that these notches rendered any further attempts on the lock 
 hopeless. The false notches are not so deep as the true; they 
 will permit the barrel to turn partially but not wholly round. 
 But even supposing that the false notch had been hit upon in 
 nearly every slide instead of the true, and that the barrel had 
 been partially turned to the extent which these notches per- 
 
112 
 
 ON LOCKS. 
 
 mitted, there would then be a binding action at the false 
 notches different from that in the true, and this would guide 
 the operator in his search for the time notches. It would not 
 add a new principle different from the one before in action, 
 but it would add to the time during which the search would 
 have to be carried on. 
 
 We make these remarks in connection with Mr. Ainger’s 
 article, which was probably written twenty years ago. We 
 now come to the year 1850. 
 
 At the meeting of the Institution of Civil Engineers, when 
 Mr. Chubb’s paper was read, many challenges and counter- 
 challenges were made, as to the possibility of picking certain 
 locks. Mr. Chubb described, among others, a lock on the 
 patent of Mr. Davies, which, ingenious though it be, he con¬ 
 siders not safe. Captain D. O’Brien differed from Mr. Chubb 
 in this matter; he had had occasion to open from ten to 
 twenty of Davies’s cabinet-locks daily, during a period of two 
 years, and he never once observed the locks to be out of 
 order; in fact, they always appeared to afford great security. 
 Mr. Chubb thereupon rejoined, that he was prepared to pro¬ 
 duce a workman who would pick any number of Davies’ 
 cabinet-locks, of different combinations, which he had never 
 seen before, taking only half an hour for each lock. 
 
 As another instance, Captain O’Brien stated that, in his 
 capacity as Inspector of Government Prisons, his attention had 
 been much directed to the subject of secure locks; and he 
 produced, among others, specimens of those in use at the 
 Pentonville Prison; though not of first-rate workmanship, he 
 characterised them as being safe, strong, and cheap. They 
 were on Thomas’s principle. The locks had been in use 
 eight years, during which period not one had required to be 
 replaced; and any trifling derangements had been made good 
 whilst the prisoners were at exercise. Mr. Chubb, after mak¬ 
 ing his offer concerning Davies’s lock, stated that “ he was 
 willing to make the same offer with respect to the locks from 
 the Pentonville Prison; and he might state that, in point of 
 
THE LOCK CONTROVERSY. 
 
 113 
 
 security, he considered them absolutely worthlessin proof of 
 which he exhibited one of them, and a common burglar’s tool, 
 by which the lock could be opened with the greatest ease. 
 
 In respect to Bramah’s lock, there was no particular chal¬ 
 lenge associated with the proceedings of the evening; but 
 incidental observations were made as to the degree of security 
 pertaining to it. Mr. Farey, after passing a high eulogium on 
 the ingenuity of the principle and the beauty of the workman¬ 
 ship, considered it nevertheless objectionable that the sliders 
 should be so completely exposed to view. He then proceeded 
 to make the following observations: “It had been suggested, 
 that a universal false key for Bramah’s locks might be made, 
 with the bottoms of its several notches formed by as many 
 small steel sliders, extending beyond the handle of the key, so 
 as to receive pressure from the fingers, for moving each one 
 of the sliders within the lock, with a sliding motion in its 
 own groove, independently of the other. During such sliding 
 motion, a gentle force could be exerted, tending to turn the 
 barrel round. Under such circumstances, supposing that the 
 motion of the barrel was prevented by any one slider only; 
 that one, having to resist all the turning force, would be felt 
 to slide more stiffly endways in its groove, and therefore it 
 could be felt when its unlocking notch arrived opposite the 
 steel plate, and left some other slider to begin to resist the 
 turning force. Such a circumstance (continues Mr. Farey) pre¬ 
 sumes a palpable inaccuracy in the radiating correspondence 
 between the notches in the steel plate and the grooves for the 
 sliders in the barrel, which could not happen with Bramah’s 
 workmanship.”* He further remarked: “Unfortunately, if a 
 Bramah’s key fell into dishonest hands, even for a short time, 
 an impression could be easily taken, and a false key as easily 
 made. A turkey-quill, notched into the form of a key, had 
 sufficed to open a Bramah’s lock; and an efficient false key 
 ctuld be formed out of a pocket pencil-case. Such facility 
 of fabrication was an invitation to dishonesty; and as an 
 * See also Mr. Owen’s suggestion, p. 59, ante. 
 
114 
 
 ON LOCKS. 
 
 abortive attempt left no trace, the impunity was an encourage¬ 
 ment to repeat the attempt until success is attained.” 
 
 With respect to Chubb’s locks, a discussion arose out of 
 a statement made by Mr. Hodge. Mr. Chubb had himself 
 stated it to be a general opinion that a skilful workman, 
 furnished with impressions taken from the true key, in wax 
 or soap, could make a false key to open any lock; and he 
 considered that, in common locks, with the most elaborate 
 wards, but with only one tumbler, as also in Bramah’s 
 locks, there was much truth in the notion. In respect to 
 his own lock, however, with six double-acting tumblers, “ a 
 false key made ever so carefully from impressions would 
 not be likely to open the lock, for want of exactitude in 
 the lengths of the several steps; and if the key could not be 
 made exact from the impressions, there would be no chance 
 of rectifying it by trial in the lock, on account of the total 
 uncertainty as to which part required alteration.” Mr. Hodge 
 stated that, in America, he had repeatedly seen impressions 
 taken of locks having twelve or fourteen tumblers, in con¬ 
 sequence of the bellies of the tumblers, when at rest, coinciding 
 with the form of the key (see page 63). He also suggested a 
 method of taking an impression of the bellies of the tumblers ; 
 but Mr. Chubb, Mr.Farey, Mr. Stephenson, and Mr. Whitworth, 
 all expressed a disbelief that a Chubb’s lock could be opened 
 by the means indicated by Mr. Hodge. Mr. Hodge admitted 
 that he was not aware of any lock actually made by Messrs. 
 Chubb having been picked in America; but that the locks to 
 which lie had adverted were such exact imitations, that he had 
 no doubt of the Chubb lock yielding to similar treatment. He 
 further stated that there were persons in New York who would 
 undertake to pick a real Chubb lock. 
 
THE LOCK CONTROVERSY. 
 
 115 
 
 CHAPTER IX. 
 
 THE LOCK CONTROVERSY: DURING AND SINCE THE TIME OF THE 
 GREAT EXHIBITION. 
 
 We next come to the remarkable year 1851, which produced 
 so many unexpected results in connection with the industrial 
 display in Hyde Park, and conferred a lasting benefit on the 
 useful arts and manufactures of the United Kingdom, by 
 bringing their products into contrast and competition with 
 those of other nations. It was to be expected that such a trial 
 as this would afford evidences of national failure as well as of 
 success ; but probably no one suspected before the trial, that 
 English locks, so celebrated over the greater part of the world 
 for skilful mechanical design, beauty of workmanship, and 
 perfect inviolability, would readily yield to a well-arranged 
 system of lock-picking. Such, however, was the case; and 
 we are bound to admit that Mr. Hobbs, the author of this 
 system, is a mechanician of great skill, and with a profound 
 knowledge of the art of the locksmith. 
 
 The first step in the celebrated lock controversy of 1851 
 was taken by Mr. Hobbs himself, who declared to a party of 
 scientific men in the Crystal Palace, that all the locks made 
 in this country up to that date admitted of being very easily 
 picked; and in order to explain to these gentlemen the prin¬ 
 ciple upon which this was to be done, Mr. Hobbs picked one 
 of Chubb’s patent detector-locks in their presence in a few 
 minutes. 
 
 The fairness of this experiment havingbeen called in question 
 by certain persons who were not present at the time when it 
 was made, Mr. Hobbs, on July 21st, 1851, wrote a letter from 
 the American department of the Great Exhibition, to Messrs. 
 Chubb, simply announcing that an attempt would be made, 
 on the next following day, to pick a lock manufactured by 
 
116 
 
 ON LOCKS. 
 
 them, and which was at that time on the door of a strong room 
 in a house named by Mr. Hobbs. Messrs. Chubb were in¬ 
 vited to be present at the operation; but no member of the 
 firm attended. What occurred on the day specified may best 
 be given in the words of a letter written by those who wit¬ 
 nessed the operation. 
 
 ‘'London, July 22, 1851. 
 
 “We the undersigned hereby certify, that we attended, 
 with the permission of Mr. Bell, of No. 34 Great George- 
 street, Westminster, an invitation sent to us by A. C. Hobbs, of 
 the City of New York, to witness an attempt to open a lock 
 throwing three bolts and having six tumblers, affixed to the 
 iron door of a strong-room or vault, built for the depository of 
 valuable papers, and formerly occupied by the agents of the 
 South-Eastern Railway; that we severally witnessed the ope¬ 
 ration, which Mr. Hobbs commenced at 35 minutes past 11 
 o’clock a.m., and opened the lock within 25 minutes. Mr. 
 Hobbs having been requested to lock it again with his instru¬ 
 ments, accomplished it in the short space of 7 minutes, with¬ 
 out the slightest injury to the lock or door. We minutely 
 examined the lock and door (having previously had the assur¬ 
 ance of Mr. Bell that the keys had never been accessible to 
 Mr. Hobbs, he having had permission to examine the key-hole 
 only). We found a plate at the back of the door with the 
 following inscription: ‘Chubb’s New Patent (No. 261,461), 
 St. Paul’s Churchyard, London, Maker to Her Majesty.’ ” 
 
 This letter was signed with the names and addresses of the 
 following gentlemen:— 
 
 Mr. Handley. 
 
 ,, William Marshall. 
 „ W. Armstead. 
 
 „ G. R. Porter.* 
 
 ,, F. W. Wenham. 
 
 ,, A. Shanks. 
 
 Mr. T. Shanks. 
 
 Colonel W. Clifton. 
 
 Mr. Elijah Galloway. 
 
 ,, Paul R. Hodge. 
 
 ,, Charles H. Peabody. 
 
 Several of these names are well and publicly known in 
 England and the United States. 
 
 Late Secretary to the Board of Trade. 
 
THE LOCK CONTROVERSY. 
 
 117 
 
 This event gave rise to much newspaper controversy; and 
 attempts were made to shew that, as this was not a test lock, 
 prepared expressly for challenge, the picking proved nothing 
 as regards the finest of the manufacturers’ locks. Two circum¬ 
 stances, however, have to be noticed—that the lock was of suf¬ 
 ficient commercial importance to be placed on a door enclosing 
 valuable papers, and that the makers had an opportunity to 
 attend and witness, and comment on the trial, if they so chose. 
 We may here remark, that one of the ingenious contrivances of 
 the Chubb lock, the detector, excited some doubt no less than 
 fifteen years ago, as will be seen from the following. The 
 writer of the article “ Lock” in Hebert’s Engineers' and Me¬ 
 chanics' Encyclopaedia, while speaking with much commenda¬ 
 tion of Chubb’s locks, points out a curious feature, which 
 seems to him to render somewhat doubtful the surety of the 
 detector apparatus. “ In Barron’s and Bramah’s locks,” he 
 observes, “ the picker has no means of knowing whether the 
 tumblers are lifted too high or not; but in Chubb’s he has 
 only to put the detector hors de combat in the first instance, 
 by a correct thrust from the outside of the door (which might 
 be accurately measured), so as to fix it fast in its place; the 
 detector then becomes a stopper to the undue ascent of the 
 tumblers, and the extent of their range is thereby correctly 
 ascertained. Thus, it appears to us, the detector might be 
 converted into a director of the means for opening the 
 lock.” 
 
 Much will depend on the view which is taken of the cir¬ 
 cumstance just noted. The object of the detector is, not to 
 prevent the lock from being picked, but to shew that an 
 attempt has been made to pick it; or, at least, to attain a 
 given purpose by an indirect instead of a direct method. But 
 if there be really any truth in the surmise, that the detector 
 actually guides a skilful hand in determining how high the 
 tumblers should be raised, the supposed advantage will be 
 purchased at rather a dear rate. As we are here, however, 
 speaking of facts and not of mere opinions, it is proper to say, 
 
118 
 
 ON LOCKS. 
 
 that the lock opened by Mr. Hobbs had the detector apparatus, 
 but that it was not disturbed by him in picking the lock. 
 
 But instead of reiterating opinions, we will state the method 
 by which most of the tumbler-locks made in England, up to 
 the date of the Great Exhibition, can be opened or picked. 
 
 Bearing in mind the principle on which the picking of locks 
 is said to depend, namely, that “ whenever the parts of a lock 
 which come in contact with the key are affected by any pres¬ 
 sure applied to the bolt, or to that portion of the lock by which 
 the bolt is withdrawn, in such a manner as to indicate the 
 points of resistance to the withdrawal of the bolt, such a lock 
 can be picked,” the first step is to produce the requisite pressure. 
 
 If the end of the bolt were exposed, this pressure might be 
 applied by some force tending to shoot back the bolt; but as 
 the bolt, whenever it is shot, is buried in the jamb of the door, 
 or otherwise concealed from view, the pressure can in general 
 only be applied through the key-hole. In order, therefore, to 
 apply this pressure, the operator provides himself with an in¬ 
 strument capable of reaching the talon of the bolt, which in 
 the case of the Chubb lock was a pipe-key of the form shewn 
 at a b, fig. 49, furnished at the pipe-end with that portion of 
 
 AV 
 
 fig. 49. 
 
 the bit of the key b c which moves the bolt (see fig. 32, page 
 57, where the step which acts on the bolt is called the terminal 
 step). The other end of the pipe-key is made square, as at a, 
 for the purpose of receiving the square eye e of the lever e f, 
 fig. 50, to the further end of which/a weight w is attached by 
 means of a string s. Now it is evident that if this pipe be 
 introduced into the lock as far as it will go, and be turned 
 
THE LOCK CONTROVERSY. 
 
 119 
 
 round as in the act of unlocking, and the lever and weight be 
 attached to the end a, the bit b c of the pipe-key will maintain 
 a permanent pressure on the bolt, which, if the weight be 
 sufficient, will throw back the bolt as 
 
 soon as the tumblers are raised to ^ |J 
 
 the proper height to allow the stump 
 to pass. 
 
 The next step in the operation is 
 to raise the tumblers to the proper 
 height. For this purpose a second 
 pipe mn is made to slide upon the 
 first with an easy motion, and by 
 means of the cross handle h h can 
 be turned round or slid backwards 
 and forwards on the tube a b. This 
 tube m n is also furnished with a 
 
 fig. 50. 
 
 single projecting bit or step n o, corresponding with one of the 
 six steps of the key, fig. 32, and made of the proper length for 
 entering the key-hole. 
 
 Now for the operation of opening a tumbler-lock with this 
 simple apparatus. Referring to fig. 31, page 56, it will be 
 evident that if the pipe a b, fig. 49, be passed over the pin of 
 the lock and turned round towards the left, and the weight be 
 attached, there will be a tendency in the bolt to shoot back, 
 which tendency will bring the stump s, fig. 31, up against the 
 inner angle or shoulder of one or other of the tumblers, which¬ 
 ever happens to project, however slightly; or, as Mr. Hobbs 
 expresses it, “ one or more of the tumblers will bind.” By 
 moving forward the pipe m n and turning round the bit no in 
 the lock, it is easy to ascertain, by delicate touch, which of 
 the tumblers it is that binds. It may be found that all are 
 free to move except one or two against which the stump is 
 pressing with the force of the weight w, fig. 50. The bit n o 
 is therefore brought gently under the bellies of the tumblers 
 which bind, and they are moved slightly upwards until they 
 cease to bind. As soon as they are set free another tumbler 
 
120 
 
 ON LOCKS. 
 
 will bind; that is, the bolt will move through a small space, so 
 as to bring the stump into contact with that particular tumbler 
 which now projects; this in its turn is relieved, another tum¬ 
 bler binds and is relieved, and so on until the tumblers are, 
 one by one, raised to the proper height for the stump to pass. 
 When the last binding tumbler is raised to the proper height, 
 the weight w being no longer resisted, shoots the bolt back, 
 and the work is done. 
 
 Now it must be evident that in this operation the detector 
 apparatus need not come into operation. But if, as has been 
 proposed, a detector-spring be added to each tumbler, it may 
 be converted into a friend or a foe according to the use that is 
 made of it. If the tumblers are lifted too high , they will be 
 detained or detected in that position, and the operator will 
 have to release them by turning the bit round in the opposite 
 direction before he can begin his work again. The same 
 force, however, which detains the tumblers when they are 
 lifted too high will obviously detain them when they are 
 lifted only just high enough, and thus the detector-springs 
 would really be of great assistance to the operator in picking 
 such a tumbler-lock. 
 
 The apparatus which we have described for picking the 
 tumbler-lock must be varied to suit the form of key employed 
 in opening the lock; but it is not difficult, in the case of most 
 locks, to ascertain this form through the key-hole, without 
 examining the key itself. 
 
 It is but fair to state in this place, that since the above 
 method of picking tumbler-locks was made known,* Mr. Chubb 
 
 * We believe the method was first made publicly known at a special 
 general meeting of the members of the Institution of Mechanical Engineers, 
 held at the rooms of the Society of Arts, London, on the 30th June, 1851, 
 when a paper was read by Mr. Paul R. Hodge “On the progress of im¬ 
 provements in locks in the United States of America.” A report of this 
 paper, together with the discussion thereon, was published by Waterlow 
 and Sons, London Wall, 1851. Plate 34 (figs. 9 and 10) of this report 
 contains representations of the lock-picking apparatus, from which we have 
 copied our figures. 
 
THE LOCK CONTROVERSY. 
 
 121 
 
 has added a series of teeth and notches to the stump and tum¬ 
 blers ; the effect of which would evidently prevent the appli¬ 
 cation of the above method of picking, because any permanent 
 pressure applied to the bolt would send a tooth of the stump 
 into a notch of the tumbler, and prevent all further motion. 
 But recurring to the principle, that whenever the parts of a 
 lock which come in contact with the key indicate the points of 
 resistance when any pressure (whether permanent or temporary ) 
 is applied in attempting to withdraw the bolt, that lock can be 
 picked, it follows, if this principle be admitted, that although 
 the notches prevent the application of the form of instrument 
 described, yet there is sufficient indication afforded by the 
 pressure to enable a skilful operator, with proper instruments, 
 to form a false key, as was done in the case of the lock referred 
 to at page 104. We now proceed to the second stage in the 
 lock controversy of 1851. 
 
 Soon after the picking of the Chubb lock in Great George- 
 street, and consequent on the excitement and discussion to 
 which that operation led, a committee, consisting of Mr. G. 
 Bennie, Professor Cowper,* and Dr. Black, agreed to super¬ 
 intend the arrangements for a more severe testing of Mr. 
 Hobbs’s power to open locks. There had been for many years 
 exhibited in the window of Messrs. Bramah’s shop, in Picca¬ 
 dilly, a padlock of great complexity and beauty; to which an 
 announcement was affixed, that a reward of two hundred 
 guineas would be given to any person who should succeed in 
 picking that lock. This challenge was accepted by Mr. Hobbs; 
 and the committee managed all the arrangements, as arbitra¬ 
 tors between Mr. Hobbs on the one side and Messrs. Bramah 
 on the other. The lock was removed to an upper room in 
 Messrs. Bramah’s establishment; where it was placed between 
 two boards, and so fixed and sealed, that no access could be 
 
 * In mentioning the name of the late Professor Edward Cowper, we 
 cannot refrain from deploring the loss which mechanical science has suffered 
 by his too-early death. The application of mechanical principles to manu¬ 
 factures was treated by him in his lectures and illustrations with a felicity 
 which has been rarely equalled. 
 
 G 
 
122 
 
 ON LOCKS. 
 
 obtained to any part of it except through the key-hole. The 
 room was to be given up to Mr. Hobbs; he was not to be in¬ 
 terrupted by the presence or entrance of any other persons; and 
 he was allowed a period of thirty days for opening the lock. 
 If the lock was not picked at the expiration of that period, Mr. 
 Ilobbs was to be considered as having failed in his attempt. 
 
 There was much negotiation and correspondence before 
 and during Mr. Hobbs’s operation on this lock. On July 2, 
 he, with a view to this enterprise, applied for permission to 
 take wax impressions of the key-hole. This permission being 
 given, and the parties having met to discuss the necessary ar¬ 
 rangements, an agreement was signed on the 19th, reciting the 
 terms of the challenge, and providing that thirty days should be 
 allowed to Mr. Hobbs to effect his enterprise; that the lock 
 should be secured in a certain specified way; and that the key 
 should remain in the possession of Messrs. Bramah, who were to 
 retain the right of using it in the lock when Mr. Hobbs was not 
 at work. Messrs. Bramah subsequently relinquished this last- 
 mentioned privilege, in order that the trial might be perfectly 
 fair; and it was agreed that the key should be sealed up 
 during the whole period, beyond the reach either of Mr. 
 Hobbs or Messrs. Bramah; and that the key-hole should be 
 secured by an iron band, sealed, when Mr. Hobbs was not at 
 work. These and other conditions were embodied in the 
 agreement noticed in the last paragraph. 
 
 Mr. Hobbs commenced his labours on July 24th. After a 
 few visits to the lock, Messrs. Bramah -wished to have the pri¬ 
 vilege >of inspecting it, or else that such an inspection should be 
 made by the arbitrators; and, during a correspondence which 
 arose out of this request, the operations were suspended. Mr. 
 Ilobbs resumed his work on August 16. On the 23d, Messrs. 
 Bramah drew the attention of the arbitrators to the challenge, 
 that the reward of two hundred guineas was offered to the artist 
 who should make an instrument that would pick or open the 
 lock ; that he was to be paid the money on the production of 
 the instrument; and that, unless some person were present, it 
 
THE LOCK CONTROVERSY. 
 
 123 
 
 was impossible that any one could know that the lock had 
 been opened by the instrument which might be produced. 
 This letter was not allowed by the arbitrators to affect the 
 arrangements made. We may now consistently give the 
 “ Report of the Arbitrators.” 
 
 “ Whereas for many years past a padlock has been exhi¬ 
 bited in the window of Messrs. Bramah’s shop, in Piccadilly, 
 to which was appended a label with these words: ‘ The artist 
 who can make an instrument that will pick or open this lock 
 shall receive two hundred guineas the moment it is produced;’ 
 and Mr. ITobbs, of America, having obtained permission of 
 Messrs. Bramah to make trial of his skill in opening the said 
 lock, Messrs. Bramah and Mr. Hobbs severally agreed that 
 George Rennie, Esq., F.R.S., of London; and Professor Cow- 
 per, of King’s College, London; and Dr. Black, of Kentucky; 
 should act as arbitrators between the said parties. 
 
 “ That the trial should be conducted according to the rules 
 laid down by the arbitrators, and the reward of two hundred 
 •guineas be decided by them; in fine, that they should see fair 
 play between the parties. 
 
 “ On July 23 it was agreed that the lock should be en¬ 
 closed in a block of wood, and screwed to a door, and the 
 screws sealed, the key-hole and the hasp only being accessible 
 to Mr. Hobbs; and, when he was not operating, the key-hole 
 was to be covered with a band of iron and sealed by Mr. 
 Hobbs, that no other person should have access to the key¬ 
 hole. The key was also sealed up, and was not to be used 
 until Mr. Hobbs had finished his operations. If Mr. Hobbs 
 succeeded in picking or opening the lock, the key was to be 
 tried; and if it locked and unlocked the padlock, it should be 
 considered as a proof that Mr. Hobbs had not injured the 
 lock, but had fairly picked or opened it, and was entitled to 
 the two hundred guineas. 
 
 “ On the same day, July 23, Messrs. Bramah gave notice 
 to Mr. Hobbs that the lock was ready for his operations. 
 
 “ On July 24 Mr. Hobbs commenced his operations ; and 
 
124 
 
 ON LOCKS. 
 
 on August 23 Mr. Hobbs exhibited the lock opened to Dr. 
 Black and Professor Cowper (Mr. Rennie being out of town). 
 Dr. Black and Mr. Cowper then called in Mr. Edward Bramah 
 and Mr. Bazalgette, and shewed them the lock opened; they 
 [the last-named two gentlemen are of course meant] then rvith- 
 drew, and Mr. Hobbs locked and unlocked the padlock in pre¬ 
 sence of Dr. Black and Mr. Cowper. 
 
 “ Between July 24 and Aug. 23 Mr. Hobbs’s operations 
 were for a time suspended; so that the number of days occu¬ 
 pied by Mr. Hobbs was sixteen, and the number of hours he 
 was actually in the room with the lock was fifty-one. 
 
 “ On Friday, Aug. 29, Mr. Hobbs again locked and un¬ 
 locked the padlock in presence of Mr. G. Rennie, Professor 
 Cowper, Dr. Black, Mr. Edward Bramah, Mr. Bazalgette, and 
 Air. Abrahart. 
 
 “ On Saturday, Aug. 30, the key was tried, and the pad¬ 
 lock was locked and unlocked with the key, by Professor 
 Cowper, Mr Rennie, and Mr. Gilbertson ; thus proving that 
 Mr. Hobbs had fairly picked the lock without injuring it.’ 
 Mr. Hobbs then formally produced the instruments with which 
 he had opened the lock. 
 
 “ We are, therefore, unanimously of opinion, that Messrs. 
 Bramah have given Mr. Hobbs a fair opportunity of trying 
 his skill, and that Mr. Hobbs has fairly picked or opened the 
 lock; and we award that Messrs. Bramah and Co. do now pay 
 to Mr. Hobbs the two hundred guineas. 
 
 George Rennie, Chairman. 
 
 Edward Cowper. 
 
 J. R. Black. 
 
 Holland Street, Blackfriars, 
 
 Sept. 2, 1851.” 
 
 It may be here stated, in reference to the space of time 
 during which the operations were being conducted, that the 
 actual opening of the lock occurred much earlier, so far as 
 concerned the principle involved, though not in a way to meet 
 the terms of the challenge. On his fifth visit, Mr. Hobbs sue- 
 
THE LOCK CONTROVERSY. 
 
 125 
 
 ceeded in adjusting the slides and moving the barrel, prepara¬ 
 tory to withdrawing the bolt; but the instrument with which 
 the barrel was to be turned round, being too slight, slipped, 
 and defeated the operation. Mr. Hobbs had then to readjust 
 the barrel, and to make a new instrument to aid him; this 
 new instrument, when completed, enabled him to open the 
 lock in the space of an hour or two. 
 
 On the same day Messrs. Bramah addressed a letter to the 
 arbitrators, stating the reasons which induced them to think 
 that, though Mr. Hobbs had succeeded in opening the lock, 
 the manner of doing so did not come within the meaning of 
 the challenge originally made by them. The arbitrators, 
 however, were unanimous in their award, and Messrs. Bramah 
 bowed to it. 
 
 In an article written in one of the daily newspapers im¬ 
 mediately after the opening of the lock, the following notice 
 was given of the lock and its production: “ We were surprised 
 to find that the lock which has made so much noise in the 
 world is a padlock of but 4 inches in width, the body of it 1J- 
 inches thick, and its thickness over the boss 2 J inches. Upon 
 opening the outer case of the lock, the actual barrel enclosing 
 the mechanism was found to be inches in length and 11- 
 inches in diameter. The small space in which the works were 
 confined, and its snug, compact appearance was matter of asto~ 
 nishment to all present. The lock and key were made forty 
 years since by the present head of the eminent firm of Messrs. 
 Maudslay and Co., Mr. Maudslay being at that time a work¬ 
 man in the employ of Mr. Bramah.” 
 
 We may here remark, as indeed has been remarked in 
 former pages, that the Bramah lock is, and -will probably con¬ 
 tinue to be, deservedly celebrated for the amount of mechanism 
 contained in a small space, as adverted to in the last para¬ 
 graph. The cylindrical form is well calculated for this con¬ 
 centration of power within narrow limits; and the smallness of 
 the key is a great merit. 
 
 The objections made by Messrs. Bramah to the award of 
 
126 
 
 ON LOCKS. 
 
 the committee were embodied in the following letter to Mr. 
 Rennie, dated 9th September: 
 
 “ Dear Sir, —We beg to acknowledge your letter of yester¬ 
 day’s date, and will not trouble you to attend here to-morrow, 
 but beg to hand you the 210/. awarded by the arbitrators to 
 Mr. Hobbs. We need scarcely repeat that the decision at 
 which the arbitrators have arrived has surprised us much; 
 and we owe it to ourselves and the public to protest against 
 it. We do so for the following reasons : 
 
 “ 1. Because the arbitrators, having been appointed to see 
 fair-play, and that the lock was fairTy operated upon, did not, 
 although repeatedly requested in writing to do so, once inspect 
 or allow any one to witness Mr. Hobbs’s operations during the 
 sixteen days he had the sole custody of the lock and was en¬ 
 gaged in the work. 
 
 “ 2. Because the arbitrators did not once exercise their right 
 of using the key, although repeatedly requested in writing to 
 do so, till after Mr. Hobbs had completed his operations; and 
 then, instead of applying at once to prove that no damage had 
 been done to the lock, allowed him twenty-four hours to repair 
 any that might have occurred. 
 
 3. “ Because the lock being opened by means of a fixed ap¬ 
 paratus screwed to the wood-work in which the lock was en¬ 
 closed for the purpose of experiment (which it is obvious could 
 not have been applied to an iron door without discovery), and 
 the addition of three or four other instruments, the spirit of 
 the challenge has evidently not been complied with. 
 
 “ 4. Because from the course adopted an opportunity of some 
 good scientific results has been taken from us; as neither ar¬ 
 bitrators nor any one else saw the whole or even the most im¬ 
 portant instruments, by which it is said the lock was picked, 
 actually applied in operation, either before or after the lock 
 was presented open to the arbitrators. 
 
 “ 5. Because during the progress of Mr. Hobbs’s operations, 
 and several days before their completion, we called the atten- 
 
THE LOCK CONTROVERSY. 
 
 127 
 
 tion of the arbitrators to what we considered the interpretation 
 of the challenge, begging at the same time that they would 
 apply the key and appoint some one to be present during the 
 residue of the experiment; feeling that whatever might be the 
 result in a scientific point of view, the reward could not be 
 awarded. 
 
 “ We would add, that we think that several points which 
 appear in your minutes should not have been mentioned in 
 your award; more especially that Mr. Hobbs on the 2d of 
 June took a wax-impression of the lock, and had made, as far 
 as he could, instruments therefrom between that date and the 
 commencement of his operations. 
 
 “We are, dear sir, 
 
 “ Your obedient servants, 
 
 “ Bra mah and Co.” 
 
 In order that the opinions of Messrs. Bramah and others 
 may be given with as much fairness as possible, on a matter 
 which they could not feel but otherwise than important to them, 
 we may state, that among the letters to which the picking of 
 the Bramah lock gave rise in the public journals, was the fol¬ 
 lowing addressed to the Observer newspaper on 10th October: 
 
 “ Sir, —This controversy having excited an unusual degree 
 of public attention for some time past, perhaps you will be 
 good enough to allow us to state in your journal, that the lock 
 on which Mr. Hobbs operated had not been taken to pieces for 
 many years, and it was only on examining it (after the award 
 of the committee) that we discovered the startling fact, that in 
 no less than three particulars it is inferior to those we have 
 made for years past. The lock had remained so long in its 
 resting-place in our window that the proposal of Mr. Hobbs 
 somewhat surprised us. After his appearance, however, no 
 alteration could of course be made without our incurring the 
 risk of being charged with preparing a test-lock for the occa¬ 
 sion ; we were therefore bound in honour to let the lock re- 
 
128 
 
 ON LOCKS. 
 
 main as Mr. Hobbs found it when he accepted the challenge. 
 No one inspected his operations during the sixteen days he 
 had the sole custody of the lock and was engaged at the work. 
 We are therefore compelled to advertise another 200 guineas, 
 in order that we may see the lock operate^ upon and opened, 
 if it be possible; and thus gain such information as would 
 enable us to use means that would defy even the acknow¬ 
 ledged skill of our American friends. We believe the Bra¬ 
 mah lock to be impregnable ; and we cannot open it our¬ 
 selves, with the knowledge Mr. Hobbs has given us. We 
 have fitted up the same lock with such improvements as we 
 now use, and some trifling change suggested by the recent 
 trial, and restored it with its challenge to our window. We 
 have not done this in a vain, boasting spirit; on the contrary, 
 we feel it rather hard that, from the way in which the former 
 trial was conducted, we are driven to adopt this course. Had 
 any one inspected Mr. Hobbs’s operations during that trial, it 
 would not have been necessary. 
 
 “ We are, sir, &c., 
 
 “ Bramab and Co.” 
 
 Messrs. Bramah are well entitled to offer any explanation 
 concerning the relative perfection of the lock in question, and 
 of one that they could now produce with certain improvements 
 in some parts of the working mechanism; but if these improve¬ 
 ments do not involve any new invention, patented or otherwise, 
 —-that is, if the lock be really a carrying out of the contriv¬ 
 ances already made public,—it is difficult to see why it should 
 not yield to the same treatment as the other. It is true that, 
 shortly after the decision of the arbitrators, Messrs. Bramah 
 exhibited a new lock in their window, and repeated their chal¬ 
 lenge in the same terms as before, with the single addition, 
 that applications were to be made in writing only. We have 
 reason to know that an application was made, and that the 
 consequence was the withdrawal of the challenge. In respect 
 to the actual contest, however, the character and position of 
 
THE LOCK CONTROVERSY. 
 
 129 
 
 the arbitrators ought surely to hold Mr. Hobbs justified in his 
 proceedings. They were not all Americans (supposing na¬ 
 tionality to give a bias in the matter); two were Englishmen, 
 both of distinguished rank in respect to mechanical know¬ 
 ledge ; and as Mr. Hobbs was as much bound by their de¬ 
 cision as Messrs. Bramah, he was entitled to claim any advan¬ 
 tage resulting from a favourable decision. 
 
 The following is a description, so far as can be given in 
 words, of the mode in which Mr. Hobbs operated on the Bra¬ 
 mah lock. The first point to be attained was to free the sliders 
 from the pressure of the spiral spring ; the spring was very 
 powerful, pressing with a force of between 30 and 40 lbs.; and 
 until this was counteracted, the sliders could not be readily 
 moved in their grooves. A thin steel rod, drilled at one end, 
 and having two long projecting teeth, was introduced into the 
 key-hole and pressed against the circular disc between the 
 heads of the sliders; the disc and spring were pressed as far 
 as they would go. In order to retain them in this position, 
 a curved stanchion was screwed into the side of the boards 
 surrounding the lock, and the end brought to press upon the 
 steel rod, a thumb-screw passing through the drilled portion of 
 the instrument and keeping it in its place. The sliders being 
 thus freed from the action of the spring, operations commenced 
 for ascertaining their proper relative positions. A plain steel 
 needle, with a moderately fine point, was used for pushing in 
 the sliders; while another with a small hook at the end, some¬ 
 thing like a crochet-needle, was used for drawing them back 
 when pushed too far. By gently feeling along the edge of the 
 slider, the notch was found and adjusted, and its exact position 
 was then accurately measured by means of a thin and narrow 
 plate of brass, the measurements being recorded on the brass 
 for future reference. The operator was thus enabled, by this 
 record, to commence each morning’s work at the poiflt where 
 he left off on the previous day. The lock having eighteen 
 sliders, the process of finding the exact position of the notch 
 in each was necessarily slow. Mr. Hobbs employed a small 
 
 G 2 
 
130 
 
 ON LOCKS. 
 
 bent instrument to perform tlie part of the small lever or bit 
 of the hey; with this he kept constantly pressing on the cylin¬ 
 der which moved the bolt. He thus knew that if ever he got the 
 slide-notches into the right place, the cylinder would rotate and 
 the lock open. He could feel the varying resistance to which 
 the sliders were subjected by this tendency of the cylinder to 
 rotate; and he adjusted them one by one until the notch came 
 opposite the steel plate. The false notches added, of course, 
 much to his difficulty; for when he had partially rotated the 
 cylinder by means of the false notches, he had to begin again 
 to find out the true ones. 
 
 This description accords pretty nearly with that given in a 
 former page ; but we reproduce it here to shew not merely 
 what might be the process adopted, but what really has leen 
 done. One circumstance ought at least to be noted in these 
 transactions — there is no mystery ; the method adopted is the 
 result of a process of reasoning candidly and openly explained. 
 
 In justice to Messrs. Bramah we thought it our duty to 
 give them an opportunity of stating what improvements they 
 had made in their locks since the date of the Great Exhibition ; 
 and accordingly, on the 28th April, 1853, our publisher ad¬ 
 dressed to Messrs. Bramah a note, stating that a Rudimentary 
 Treatise on the Construction of Lodes was being prepared, and 
 inviting them to contribute thereto. The following is a copy 
 of their reply : 
 
 “ 124 Piccadilly, May 2d, 1853. 
 
 “ Sir, —Pressure of business has prevented our sending an 
 earlier reply to your favour of the 28th ult. 
 
 “ The lock on which Mr. Hobbs operated during the Great 
 Exhibition had been made nearly forty year's, and when taken 
 to pieces the sliders were found to be in iron, instead of steel; 
 and the key-hole of the lock being three times larger than it 
 ought to fiave been, enabled the operator to fix down the spring 
 of the lock, and yet leave himself ample space to turn and bend 
 the sliders (being in iron) at pleasure. The barrel of the lock 
 in which the sliders act, instead of being whole length from 
 
TIIE LOCK CONTKOVEKSY. 
 
 131 
 
 front to back of padlock, was not quite half its proper length; 
 a serious oversight in the workman who put the lock together, 
 as the barrel being short, the sliders were necessarily so, which 
 diminished the number of notches in the sliders full one-half, 
 and to that extent diminished the security of the lock, and in¬ 
 creased the facility of the operator. 
 
 “We send for your inspection a box of guards, which will 
 shew you the barrel and sliders of our Bramah lock. You 
 will observe several notches in each slider, only one of which 
 will turn on the locking-plate, the others being what are termed 
 false, or security ones. These notches being cut only the exact 
 width of the locking-plate, require the most perfect accuracy 
 to carry each down to its proper distance. In the lock on 
 which Mr. Hobbs operated, in addition to the sliders being so 
 short, and only half the number of security-notches in each, 
 the notch which passed round the locking-plate was found to 
 be cut twice the width it ought to have been. The whole of 
 these defects have been corrected since the Exhibition. 
 
 “ We are, Sir, yours respectfully, 
 
 “ Bramah and Co. 
 
 “ per J. Smyth. 
 
 “ To John Weale, Esq., 59 High Holhom.” 
 
 In the Jury Report of the Great Exhibition, Class XXII., 
 are the following remarks : “ On the comparative security 
 afforded by the various locks which have come before the 
 jury, they are not prepared to offer an opinion. They would 
 merely express a doubt whether the circumstance that a lock 
 has been picked under conditions which ordinarily could 
 scarcely ever, if at all be obtained, can be assumed as a test 
 of its insecurity.” [page 500]. The conditions here alluded to 
 probably refer to the free access which Messrs. Bramah allowed 
 Mr. Hobbs to have to their lock during a period of thirty days, 
 and we are hence led to infer that the burglar is denied any 
 such facilities. On this point we would refer to the opinion 
 of a high authority. In a paper “ on the History and Con- 
 
132 
 
 ON LOCKS. 
 
 struction of Latches and Locks,” by Mr. Chubb, read before the 
 Society of Arts, 22d January, 1851, the following graphic 
 passage occurs : 
 
 “ In order to shew the absolute necessity of secure locks 
 and safe depositories for property, especially in banking es¬ 
 tablishments, it may not be out of place to trace the systematic 
 care and great sagacity with which the large burglaries are 
 planned. You will bear in mind that an unsuccessful attempt 
 is seldom made where the booty is of any magnitude. The 
 first-rate ‘ cracksmen’ always know beforehand where to go, 
 when to go, and what they are going for. When a 1 plant,’ 
 as it is termed, is made upon a house or a bank, precise infor¬ 
 mation is gained, if possible, as to the depository of the valu¬ 
 ables ; and if it is found that the safeguards are too strong in 
 themselves, and that the locks are invulnerable, the affair is 
 quietly dropped. But if otherwise, then no expenditure of 
 time or misapplied ingenuity is spared to gain the desired 
 end. The house is constantly watched, the habits of its in¬ 
 mates are observed, their ordinary times of going out and 
 coming in are noted ; the confidential servants are bribed or 
 cajoled, and induced to leave the premises when their em¬ 
 ployers are absent, so that impressions may be taken from 
 the locks, and false keys made. When all the keys required 
 are made, one or two men who have not been previously ini¬ 
 tiated are generally called in, and receive their instructions to 
 be ready at a certain hour on the following day to enter the 
 house. A plan of the premises is put into their hands, they 
 are cautioned to step over a certain creaking stair or plank, 
 and the keys of the different doors are given them. The day 
 or evening is chosen when it is known that the inmates will 
 be from home—the servant, taking advantage of their absence, 
 fulfils a long-standing engagement with his new and liberal 
 friends—a signal is given—the two confederates enter — the 
 so-called safe is swept of its contents, all the doors are care¬ 
 fully re-locked, and not until the bank is opened for business 
 next morning is the robbery discovered.” 
 
THE LOCK CONTROVERSY. 
 
 133 
 
 In an article in Frazer s Magazine for November 1852 the 
 following observations were made on the Exhibition Jury Re¬ 
 port on Locks: “ This jury seems to have consisted of the only 
 persons in England who did not hear of the famous ‘ lock con¬ 
 troversy’ of last year ; for one can hardly imagine that, if they 
 had heard of a matter of so much consequence to the subject 
 they w r ere appointed to investigate, they would have altogether 
 abstained from saying any thing about it. They may be ex¬ 
 cused for not knowing, because very few people did know, 
 fortunately for our safes and strong boxes, that the mode of 
 picking Bramah’s and Chubb’s locks, by Avhich the transatlantic 
 Hobbs gained so much glory, was suggested and explained in 
 the Encyclopaedia Britannica nearly twenty years ago. But it 
 does seem very strange that they, or at least their reporter, 
 should not have known, long before the Report finally left his 
 hands, that Hobbs had picked both of those locks, and taught 
 every lock-picker in England how to do it, if he possesses the 
 requisite tools and fingers. Of course, however, the reporter 
 did not know it, as nobody could read any newspaper last 
 autumn without knowing it. And this jury did exercise their 
 judgment to the extent of declaring that Hobbs’s own lock 
 (under the name of Day and Newell) ‘ seems to be impreg¬ 
 nable.’ Notwithstanding all which, they express their inability 
 to ‘ offer any opinion on the comparative security afforded by 
 the various locks that have come before them.’ The only dis¬ 
 crimination which they venture to make is, that the keys of 
 Bramah’s and Chubb’s locks are of convenient size, while 
 Hobbs’s is ponderous and bulky, and his lock complicated ; 
 and they might have added (without any very painful amount 
 of investigation), enormously expensive, in consequence of its 
 complication, and probably also more likely, on the same ac¬ 
 count, to get out of order and stick fast, and so become rather 
 inconveniently impregnable—on the money door of a bank, 
 for instance,—than the other two locks, especially Bramah’s.” 
 
 In relation to the opinion just given, it may be remarked 
 that the American lock has shewn no tendencies to get out of 
 
134 
 
 ON LOCKS. 
 
 order; if well constructed (and good construction is a sine qua 
 non in such mechanism), the parts work into and upon each 
 other with very little friction. In respect to expense, and to 
 the size of the key, a banlcA ock is not one in which economy 
 would be much studied, security being the great desideratum. 
 No attempt is made to produce a parautoptic lock of small size 
 or for cheap purposes. The lock, therefore, must be judged of 
 with reference to what it undertakes to perform. And this 
 brings us to notice the attempts made in England to pick the 
 parautoptic or American bank-lock. 
 
 The following were the circumstances connected with Mr. 
 Garbutt’s attempt to pick the American lock. It is of course 
 known that a challenge was affixed to the American lock in 
 the Great Exhibition, and it was this challenge which Mr. 
 Garbutt accepted. Mr. Garbutt, it may be here observed, 
 was a working locksmith and engineer ; he had been entrusted 
 by Messrs. Fox and Henderson with the care and adjustment 
 of the metal check-tables at the pay-places of the Crystal Pa¬ 
 lace ; he had at a previous period been in the employ of Messrs. 
 Bramah. We mention these facts only on account of an erro¬ 
 neous rumour at the time that he was an agent of Messrs. 
 Bramah in respect to the acceptance of the American challenge ; 
 whereas we believe he acted independently, by and for himself. 
 
 On Sept. 10th, 1851, Mr. A. H. Renton, Mr. E. H. Thom¬ 
 son, and Mr. W. F. Sliattuck,—the first an engineer, and the 
 other two American exhibitors, — were appointed arbitrators 
 to superintend the arrangements, and they met Mr. Garbutt 
 and Mr. Hobbs at the house No. 20 Knightsbridge. The 
 following conditions were agreed to : — That a Newell lock 
 should be selected, and should be screwed to a wooden box; 
 that Mr. Garbutt should have access only to the key-hole of 
 the lock, through which key-hole all his operations for picking 
 the lock should be conducted ; that Mr. Garbutt should have 
 uninterrupted and exclusive access to the box, between the 
 hours of nine in the morning and nine in the evening, for 
 thirty days, beginning on the 11th of September, he having 
 
THE LOCK CONTROVERSY. 
 
 135 
 
 during that time the privilege of introducing one associate, 
 and the arbitrators reserving to themselves the right of in¬ 
 specting the seals placed by them on the box ; that, in order 
 to afford every information concerning the internal arrange¬ 
 ment of the lock, the trial-lock should be taken to pieces in 
 presence of all the parties ; that it should be examined by Mr. 
 Garbutt; that it should be locked and unlocked with the pro¬ 
 per key by him and by Mr. Hobbs ; that it should be fastened 
 to a box, and the fastenings sealed by the arbitrators ; that 
 the key, when the lock was finally locked, should be sealed 
 up by the arbitrators and delivered to Mr. Hobbs, who would 
 retain it until required by the arbitrators to hand it over to 
 them. That at the expiration of the thirty days, or earlier 
 in case either of the success or the abandonment of the attempt, 
 the arbitrators should examine the lock. And, finally, that if 
 Mr. Garbutt should have succeeded in picking the lock (that 
 is, in withdrawing the bolt without injuring the lock), the sum 
 of 200Z. should be paid to him by Mr. Hobbs. 
 
 In accordance with the above agreement, Mr. Hobbs pro¬ 
 duced a parautoptic lock, with ten tumblers, marked No. 85G0. 
 The key and the lock were examined by Mr. Garbutt. The 
 lock was again put together, affixed to a box, and sealed. Mr. 
 Hobbs set the bits of the key (ten in number) to an arrange¬ 
 ment chosen by himself, and the lock was then locked by all 
 parties in succession ; the key, after the final locking, being 
 sealed up and returned to Mr. Hobbs. Mr. Hobbs at the same 
 time delivered to Mr. Garbutt a similar but smaller lock, which 
 he was to be allowed to retain during the whole period of the 
 trial, to assist in rendering him familiar with the construction 
 of both locks. 
 
 On the 11th of October, the day on which the prescribed 
 period expired, the arbitrators met at the house in question, 
 when Mr. Garbutt delivered up to them the lock miinjured, 
 but unopened. The award of the arbitrators was thereupon 
 given in the following terms : “ We therefore hereby certify 
 that Mr. Garbutt having had uninterrupted and exclusive ac- 
 
136 
 
 ON LOCKS. 
 
 cess to the lock during the period of thirty days, and, availing 
 himself of the conditions of the agreement, had every facility 
 for opening the lock that could be obtained without possession 
 of the true key, has delivered up the same into our hands un¬ 
 opened and uninjured ; and the said lock has been delivered 
 by us to Mr. Hobbs.” 
 
 It will of course be understood that it was one condition 
 of this enterprise, that the particular combination of bits in 
 the key wherewith the lock was finally locked should not be 
 seen by Mr. Garbutt. The key was in the first instance tried 
 by Mr. Garbutt and by the members of the committee, and 
 was found to turn readily in the lock ; Mr. Hobbs then left 
 the room, and re-arranged the bits of the key so as to produce 
 a new combination ; he then returned to the room, and locked 
 the lock with the key in its altered form ; he allowed all pre¬ 
 sent to feel the key turn freely, and then, without allowing 
 any one to see the combination, wrapped the key up in paper, 
 in which it was sealed as above described. Whether Mr. Gar¬ 
 butt, or any one, could have succeeded better by a momentary 
 glance at the arrangement of the key, was not at that moment 
 the question : the terms of the challenge were that he should 
 not see it. What are the circumstances likely to occur if the 
 operator really has access to the key (provided the bits are not 
 very numerous) we may shortly explain. 
 
 It is necessary to draw a distinction between picking of a 
 lock and ringing the changes on a permutating keg; otherwise 
 some of the late occurrences connected with locks can hardly 
 be understood. After the reading of a paper by Mr. Hobbs 
 before the Society of Arts, a discussion arose, in which it 
 w r as stated that the Newell lock had been picked in London. 
 Mr. Hobbs deemed it necessary to refute this statement. The 
 report was circulated in many of the London newspapers; and 
 Mr. Jeremiah Smith, the operator in question, supported it by 
 his own statement. Under these circumstances Mr. Hobbs, 
 on April 2, 1852, addressed a letter to the editor of the 
 Observer; of which the following paragraph was intended to 
 
THE LOCK CONTROVERSY. 
 
 137 
 
 point out the distinction above mentioned between “ picking” 
 and “ ringing the changes 
 
 “ Early last autumn I lent to Mr. Potter, of South Molton 
 Street, one of my locks, for the purpose of giving him an 
 opportunity to make himself acquainted with its principle and 
 construction. After he had had the lock in his possession 
 several weeks, a report reached me that one, of Mr. Potter’s 
 workmen had picked my lock. I immediately called on Mr. 
 Potter to ascertain the fact. Mr. Potter informed me that 
 for the purpose of testing the possibility of opening the lock 
 by means of an impression taken, or a copy being made of 
 the true key, Mr. Smith had made a copy of the key by 
 means of a transfer instrument, which instrument he shewed 
 me at the time. After the key was made, it was tried, and 
 found to lock and unlock the lock as readily as the original 
 key. Mr. Potter then sealed the screws of the lock, changed 
 the combination of the key, and locked it. Mr. Smith then 
 took the lock, and with the key that he had made by copying 
 the original, hit the combination, and unlocked it. The lock 
 was of the smallest size, having but six tumblers; the number 
 of changes that could possibly be made were 720. The time 
 occupied by Mr. Smith, according to his own statement, was 
 six hours and fifty-five minutes; this, allowing one minute for 
 each change, would give him time to have made 415 out of 
 the 720 changes before hitting the right one. I asked Mr. 
 Smith why he did not use the original key instead of making 
 a copy ? His answer was, that ‘ he could change the one he 
 made faster, as he did not have to screw the bits in.’ Any 
 person will readily understand the difference between ringing 
 the combination of a key and picking a lock.” 
 
 In other words, the process was this: the operator had 
 the true key, and might have used either this or one which 
 he made from it. This would have sufficed for opening almost 
 any lock ever constructed instantly; but in the American lock 
 he had to find out which of 720 combinations was the right 
 one, and he was employed almost seven hours in doing this. 
 
138 
 
 ON LOCKS. 
 
 The exploit shewed patience, but had little bearing on the 
 practical subject of lock-picking. 
 
 In March 1852 Mr. Smith put forth an offer to accept 
 the challenge made by Mr. Hobbs in respect to the Exhibition 
 lock. Mr. Ilobbs agreed to the offer, and chose, as arbitrators 
 on his part, Mr. Ilensman, Engineer to the Bank of England, 
 and Mr. Appokj, inventor of the centrifugal pump which at¬ 
 tracted so much attention at the Great Exhibition. Mr. Hobbs 
 requested Mr. Smith to appoint arbitrators on his side also; 
 but this was not done. Mr. Smith, at a meeting held by the 
 four persons named, expressed a wish that an ordinary com¬ 
 mercial lock should be the one experimented on, instead of 
 the more complicated test-lock which had been at the Great 
 Exhibition. This was a departure from the terms of the 
 original challenge ; but Mr. Hobbs waived his objection on 
 this point, and offered to substitute a bank-lock -with ten 
 tumblers for the Exhibition lock with fifteen, the former being 
 similar in construction but less complex. Another meeting 
 was agreed upon, but Mr. Smith did not attend ; and the 
 matter was, by himself, brought to a sudden termination. 
 
 To shew the effect of difference in the number of tumblers 
 and key-bits, we may state that, while, at a minute per change, 
 it would take twelve hours to go through all the combinations 
 with a six-bitted key, it would require seven years with a 
 ten-bitted, and 2,500,000 years with a fifteen-bitted key! So 
 much for power of combination, in the arithmetical mode of 
 picking. 
 
 We now proceed to notice the violability of sundry minor 
 locks. It might at first appear that the letter-lock is exceed¬ 
 ingly difficult to pick; and so it unquestionably is, as long as 
 we merely attend to the chance-medley trials by turning the 
 rings round and round until we happen to hit upon the right 
 combination. But there is another mode of solving the riddle, 
 mechanical rather than arithmetical. A piece of common wire, 
 bent in the form of the shackle, is put in between the ends 
 of the lock; the spring or elasticity of the wire tends to force 
 
THE LOCK CONTKOVEKSY. 
 
 139 
 
 tlie ends apart; this causes the pins or studs on the rod to 
 press against the inner edges of the rings. By trying all the 
 rings in succession, some one of them will be found to bind 
 or cling more than the others; this is turned round until the 
 cessation of the bind shews that the notch in the ring lias 
 been brought into its right position relatively to the pin on 
 the rod. Then another ring which binds more than the rest 
 is treated in a similar way; until at length all the rings seem 
 to be so far liberated as to indicate that the notches are in 
 the right positions. In the dial-lock, similarly, when a pres¬ 
 sure has been brought to bear upon the bolt in the right 
 direction, a trial of the pointers will soon bring the notch in 
 each wheel to the required position. 
 
 Some short time after the events in London connected with 
 the lock controversy, Mr. William Brown of Liverpool de¬ 
 scribed the letter-lock noticed in a former page, characterising 
 it as a lock which he believed no one could pick. An incident 
 in the history of this lock was thus narrated in one of the 
 Liverpool newspapers. “ Mr. Hobbs was taken by Mr. Milner 
 to the office of Messrs. Brown, Shipley, and Co., and shewn 
 this lock. The safe-door was closed and locked by the cashier 
 at Mr. Brown’s request; and then Mr. Hobbs began to illus¬ 
 trate his views of the construction of the lock by manipulation 
 and explanation, with which the subject of them appeared to 
 sympathise so entirely and promptly that the door opened in 
 a few minutes.” 
 
 In respect to the picking of the Egyptian lock, the main 
 difficulty would be in obtaining any false key that would cor¬ 
 respond with the pins of the lock; but this might be accom¬ 
 plished in a way analogous to that which is practised in many 
 other cases. If a small piece of wax be laid on a blank key, 
 the key inserted into the lock, and the blank pressed upwards 
 against the pin-holes, there would be left an impression of 
 those holes on the wax; this impression would furnish a guide 
 to the fabrication of a false key. There is also very little dif¬ 
 ficulty in picking this lock by one of the ordinary instruments. 
 
140 
 
 ON LOCKS. 
 
 For the Yale lock, combining something like the pin-action 
 of the Egyptian with the cylinder-action of the Bramah locks, 
 the picking requires the use of an instrument that will fit 
 between two of the pins, and to the outer end of which is 
 attached a lever and weight; by this means a pressure is 
 exerted upon the cylinder in the right direction for it to turn, 
 and the pins are made to bind. Then, with another instru¬ 
 ment, the pins are felt, and each one moved until it seems to 
 be relieved from the bind: this indicates that the joint in the 
 pin coincides with the joint between the two cylinders; and 
 when all have been similarly treated, the weight acting on the 
 inner cylinder will turn it. It is evident that this method is 
 the same in principle as the one applicable to the Bramah 
 lock. 
 
 CHAPTER X. 
 
 EFFECTS OF THE GREAT EXHIBITION OF 1851 IN IMPROVING 
 ENGLISH LOCKS. 
 
 We have now to refer to the effects of the lock controversy. 
 It was no doubt annoying to be told, on good authority, that 
 the machines on which we so much prided ourselves were 
 wrong in principle; and that our locks, in order to afford the 
 degree of security which are expected of such contrivances, 
 must be re-constructed. The grumbling with which the first 
 part of this proposition was received would alone have suf¬ 
 ficed to lead to a suspicion of its truth, if the large number 
 of new locks that have actually appeared had not confirmed 
 it. Whether the second part of the proposition has been fairly 
 carried out, is a point which must now be considered. 
 
 One of the first locks produced during or immediately after 
 the lock controversy was Mr. Parnell’s, to which the bold term 
 
parnell’s lock. 
 
 141 
 
 of patent defiance loch is attached. This lock is said to depend 
 for its security on a mode of arrangement which may best be 
 described in the inventor’s own words: “ Viewing the lock from 
 . its exterior, it presents nothing remarkable; but, upon removing 
 . the plate, it will be seen that all possible access to the mechanism 
 with false or surreptitious keys is effectually prevented by a solid 
 cylinder of hardened [?] brass, with protecting wards extending 
 the whole depth of the lock, and having in the centre the aper¬ 
 ture for the key, which fits to a mathematical nicety so exact as 
 to preclude the possibility of any second instrument being used 
 
 to open it.This protecting cylinder must revolve 
 
 with the key to get to the works; and the moment it passes 
 from the key-hole in going round to lock or unlock, the solid 
 portion moves into its place, and so completely closes that 
 aperture that the point of a pin, or a fine steel-pen, has failed 
 to be inserted between it and the outer plate or cap, to say 
 nothing of the utter hopelessness of perforating the metal.” 
 
 I The cylinder or protecting cap, though it revolves by the 
 action of the key somewhat in the same way as the cylinder 
 of the Bramah lock, appears to be intended rather for closing 
 or protecting the key-hole than for governing the move- 
 
 I ments of the bolt. The internal arrangements of the lock 
 are as follow: Supposing the bolt to be shot, and to be 
 about to be unlocked, the key, by the time it has made 
 i about one-third of a rotation, meets with a forcible resistance 
 ; in the shape of an upright spring-bolt or detector of strong 
 li steel acting on the revolving cylinder. The key passes this 
 detector, and arrives at the levers or tumblers. In the bolt- 
 j stud which works in the slot of these tumblers there is a 
 small deep serrated notch on one side, corresponding to similar 
 notches on each of the tumblers; if, therefore, the bolt be 
 forced, these notches would lock into each other in a similar 
 manner to the catch on a ship’s windlass or a hoisting crane. 
 There is also a double-action tumbler-bolt, so adjusted, that if 
 any of the tumblers be overlifted, this little appendage becomes 
 thrust down at one end into the bolt of the lock, where it 
 
142 
 
 ON LOCKS. 
 
 wedges all fast until the tumblers become properly re-adjusted. 
 The double-action tumbler-bolt also falls into the lock-bolt 
 when the latter is locked or shut, thereby imparting an addi¬ 
 tional strength to the lock. The key has a power of expansion 
 or enlargement while turning in the lock ; it meets with an ec¬ 
 centric plate which draws out the bits somewhat; so that, at the 
 moment of acting on the tumblers, they protrude farther from 
 the pipe of the key than when the key entered the key-hole. 
 The key is, in fact, larger when in than when out of the lock. 
 There is connected with the works of the lock a ‘ detention- 
 cap,’ so formed that, in the event of a false key being used, a 
 powerful bolt instantly locks into the revolving cylinder, and 
 holds fast the surreptitious instrument.” Such is, in substance, 
 the account which Mr. Parnell has given of his own lock. It 
 must, however, be stated, that the points of security or novelty 
 claimed by Mr. Parnell for his lock were patented by previous 
 inventors. The revolving cylinder or curtain was claimed 
 by Mitchell and Lawton in the patent of 7th March, 1815, as 
 noticed at page 52 ante. The expanding key-bit was claimed 
 by Mr. Machin of Wolverhampton in 1827, as noticed at 
 page 61, and by Mr. Mackinnon (page 62); while the serrated 
 notches in the tumbler were used by many lock-makers long 
 before the date of Mr. Parnell’s patent. The detention-cap for 
 catching and holding a false key when put into the lock was 
 also patented by Mitchell and Lawton, as noticed at page 
 53 ante. 
 
 We come now to notice a lock lately invented by Mr. E. 
 B. Denison (the author of the Rudimentary Treatise on Clocks 
 in this series), which has the merit of combining considerable 
 novelty in construction with security. After the details given 
 in the two preceding chapters, it will certainly be no small 
 praise when we express our conviction that in the present state 
 of the art of lock-picking, this lock may be considered as secure. 
 Mr. Denison has furnished us with a description of his lock, 
 which we insert almost in his own words. Mr. Denison claims 
 for this lock the following advantages- 
 
MU. DENISON S LOCK. 
 
 143 
 
 1. That a very large and strong lock on this construction 
 only requires a very small key. 2. That no key is required 
 to lock it, although it is free from the inconvenience pertaining 
 to spring-locks, viz. that the door cannot be shut without lock¬ 
 ing itself. Moreover this lock is more secure than any spring- 
 lock can be. 3. That it cannot get out of order from the 
 usual causes of the tumblers sticking together or their springs 
 breaking, inasmuch as the action of the tumblers does not 
 depend on any thing but the key and the handle, and there are 
 no tumbler-springs. 4. That for the same reason, the parts of 
 this lock do not require any polishing or delicacy of execution. 
 5. That the key-hole being completely closed by a curtain, ex¬ 
 cept when the key is in, the lock is protected from the effects 
 of the atmosphere and dust entering at the key-hole. 6. That 
 this lock is secure against any known mode of picking; the 
 smallness of the key-hole prevents the insertion of any instru¬ 
 ment strong enough to open the lock by violence. 7. That 
 this lock, from the simplicity of its construction, admits of 
 being made at small cost. 
 
 These objects are accomplished as follows:—In the large¬ 
 sized locks, such as would be used for safes and large doors, 
 the tumblers T, fig. 51, are made of pieces of hoop-iron, 6 or 7 
 inches long and 11 inch wide: these tumblers are supported by 
 and turn on a pin ci, placed at about the middle of their length; 
 so that being balanced on the pin, or nearly so, and having 
 their separating plates p between them, which cannot turn, the 
 tumblers will stand in any position indifferently; and in order 
 to secure sufficient friction to keep them steady, one or more 
 of the separating plates p is bent a little, so as to act as a spring 
 when the cap of the lock is screwed down. The lock is shewn 
 in fig, 51 as locked, the bolt b having been shot by the fan¬ 
 tailed piece f on the handle, and the tumblers sent down, so 
 that the stump s cannot enter their jaws by the other piece of 
 the handle; and it is evident that the handle cannot draw the 
 bolt back again until the tumblers have all been raised by the 
 key to the proper position to allow the stump s to enter their 
 
141 
 
 ON LOCKS. 
 
 jaws. It will be observed that in the position shewn in the 
 figure, the stump does not touch the tumblers; and conse¬ 
 quently, so long as the bolt is kept in the position represented, no 
 pressure of the stump against the tumblers can be felt, although 
 by means of a false key or pick-lock the tumblers be raised to 
 any height. No implement, however, can be pushed into the 
 key-hole without first pressing in the curtain k, which is held 
 up against the cap of the lock by the two spiral springs c c on 
 each side of the key-hole; and at the back of the curtain there 
 is a square plug p, which goes through a hole in the back of 
 the lock, and has a notch in it through which the bolt can pass 
 -when the curtain is up, closing the key-hole, but at no other 
 time. In other words, the act of pushing in the key sends 
 down the curtain plug, the effect of which is to hold the bolt 
 fast in the position in which the stump cannot be made to touch 
 the tumblers. If the proper key be used and turned about 
 half round to the right, it will bring the tumblers to the 
 proper height for the stump to pass. The key is then taken 
 
 fie. 51. Mr. Denison’s large lock. 
 
 out; for so long as it is in the lock, the bolt cannot be moved; 
 and then turning the handle to the right, the bolt is drawn and 
 the door opened. 
 
 The handle h should be so made, that as soon as the fan- 
 
me. denisoe’s lock. 
 
 145 
 
 tailed piece f has sent the bolt just clear of the tumblers, the 
 other arm to the right of h may begin to move the tumblers; but 
 the fantail need not send the stump above one-sixteenth of an 
 inch beyond the tumblers; and the curtain-plug and bolt must 
 be so adjusted that the curtain cannot be pushed in until the 
 bolt is so far out that the stump is this one-sixteenth of an inch 
 beyond the tumblers. The curtain k need only be a thin piece 
 of steel, and the bolt B must be thick enough for the curtain to 
 go down just to the level of the thin plate p between the bolt 
 and the first tumbler t. The curtain-plug p is made as long 
 as the key-hole and rather broader, and of the shape repre¬ 
 sented, partly for the sake of steadiness in pushing in the 
 curtain, and also for more completely protecting the key-hole; 
 for if an attempt be made to pick the lock by drilling into the 
 key-hole, the drill will pass into the inside of the door and not 
 into the inside of the lock.* 
 
 It is true that iron safes have been made for some years in 
 which any number of large bolts are shot by a handle and then 
 locked by a very small key. But in such locks the key must 
 be used in locking, and this leads to certain objections, viz. 
 the key must occasionally at least be confided to some person 
 whose duty it is to lock up the safe after the owner has left 
 the place ; there is also the temptation to leave the key in the 
 lock, since it will be wanted in locking up; and thus there is 
 the danger of some dishonest person taking an impression of 
 the key. Besides this, the real strength and security of such 
 safes is only that due to the small lock which locks into the 
 main bolt; whereas in Mr. Denison’s lock the security and 
 strength are those due to the lock itself, with its large and 
 
 * Mr. Denison informs us that there is a further contrivance, which he 
 will explain privately to any persons who wish to manufacture these locks, 
 of which the object is, not to add any thing to the security of the lock under 
 ordinary circumstances, hut to provide against the unusual case of a very 
 dexterous thief having occasional access to the lock when open ; in which 
 case (but for some such further provision) he might manage to construct a 
 false key capable of opening the lock at any other time, by a method which, 
 for obvious reasons, it is not advisable to publish. 
 
 H 
 
146 
 
 ON LOCKS. 
 
 strong tumblers, and other provisions peculiar to its construc¬ 
 tion ; and the hey for a lock of the largest size, which was 
 lately exhibited at the Society of Arts by Messrs. S. Mordan 
 and Co., the makers, only weighs a little more than a quarter 
 of an ounce. It may be mentioned that for large locks the key 
 may be solid, although in the small ones it is more convenient 
 to have a pipe-key, on account of the different construction of 
 the curtain. 
 
 The arrangement of the small lock for drawers, Ac. is 
 somewhat different from that of the large ones, and will be 
 understood by referring to fig. 52. The action of the handle 
 
 fig. 52. Mr. Denison's small lock. 
 
 ii on the bolt b and on the tumblers t is sufficiently clear from 
 the figure. The curtain in this case has no plug, but is only 
 a flat plate held up by a thin spring behind it, and moving 
 up and down on the drill-pin of the key, and kept from turn¬ 
 ing by having one edge against the side of the lock. The bolt 
 has a kind of second stump, only coming up so high as to be 
 able just to pass under the corner of the curtain when it is up, 
 but not able to pass when the curtain is at all pressed down by 
 any thing inserted in the key-hole. In a drawer lock the key 
 has only to be turned a quarter round in order to raise the 
 tumblers. In small locks, the friction of the tumbler-plates is 
 
MR. CHUBB’S NEW LOCKS. 
 
 147 
 
 quite enough to keep them in any position, without putting the 
 pin in the middle so as to balance them, as in large locks with 
 heavy tumblers. 
 
 In the making of these locks the key must be made first, 
 with proper provisions to prevent the repetition of the same 
 pattern ; a kind of pattern or model for locks of each size 
 should be made ; the tumblers put on the pin with plates of 
 the intended thickness between, and when raised by the key to 
 the proper height they should be clamped down ; and the 
 jaws for the stump of the bolt may then be cut by a circular 
 saw moving in a slit in the model corresponding to the place of 
 the stump. The tumblers for large locks may be cut off from 
 a strip of hoop-iron to the proper lengths by a stamping cutter, 
 giving them the proper circular end, and a punch might at the 
 same time make the pin-hole in the middle. The tumblers for 
 small locks should be stamped out of sheet brass or iron. 
 
 It will thus be evident that from the general simplicity of 
 construction, and the small amount of finish required in the 
 working parts, this lock can be made at small cost. We 
 may also add that this lock is as creditable to the public spirit 
 as to the mechanical skill of the inventor ; for the lock is not 
 patented, patents being, in Mr. Denison’s estimation, obstruc¬ 
 tions to the progress of science. 
 
 The next residt of the “ lock controversy” which we have 
 to notice is the production of not less than three improved locks 
 by Messrs. Chubb. We thought it our duty to invite the 
 attention of this celebrated firm to the preparation of this 
 Rudimentary Treatise, and in answer to the application of 
 our publisher we received the following communication from 
 Messrs. Chubb, which we insert verbatim:— 
 
 “ It will not be necessary to describe the lock as originally 
 made, as a description of it will be found in Mr. Chubb’s 
 paper read before the Institution of Civil Engineers. 
 
 “ Lock No. 1.—The first of the improvements introduced 
 consists of a barrel, to which a circular curtain is attached, 
 revolving round the drill-pin in the lock; so that if any instra- 
 
148 
 
 ON LOCKS. 
 
 ment is introduced to attempt to pick it, the curtain imme¬ 
 diately closes up the key-hole, and prevents the introduction 
 of any auxiliary instruments, there being several required in 
 action at once to produce any effect. 
 
 “ If by any means these several instruments can be intro¬ 
 duced simultaneously, the barrel keeps them all confined in a 
 very small space, preventing their expansion, and renders it 
 impossible to work them independently of each other; therefore 
 they are of no avail, being incapable of acting as more than a 
 single pick, which is perfectly useless. The barrel and curtain 
 have each been previously used separately in locks, but until 
 patented by Mr. De la Fons in 1846 they had not been used 
 in combination. Neither of them, used separately, is of much 
 use, but when combined they afford a very great security. 
 Locks have been, and still are shewn, containing either the 
 barrel or curtain singly , and as these have been picked, it has 
 been asserted that the improvement now introduced in Chubb’s 
 lock is equally insecure ; but a slight examination of the dif¬ 
 ference in their construction will prove the contrary. Mr. 
 Chubb has purchased the patent-right of this part of Mr. De 
 la Fons’ invention, and applies it to all his locks. 
 
 “ Lock No. 2.—The next improvement, recently patented i 
 by Mr. Chubb, is based upon the assumption that there may 
 be a possibility of overcoming the security of the barrel and 
 curtain as already described (although this assumption is not 
 in the slightest degree admitted), and consists in applying what 
 is called a ‘ tumbler-bolt,’ working on a hinge connected with 
 the main bolt. The web of the key does not in any case touch 
 the main bolt in unlocking, but acts only on the tumbler-bolt. 
 All the tumblers must first be lifted, each to its proper position, 
 before the tumbler-bolt will act. Should any pressure be ap¬ 
 plied to either bolt before the tumblers are all at their exact 
 position, the effect would be to throw the bolts out of gear, and 
 thus effectually to stop the stump of the main bolt from passing 
 through the racks of the tumblers. None of the many plans of 
 picking which have been suggested, such as smoked key-blanks, 
 
mr. chubb’s new locks. 
 
 149 
 
 thin key-bits, &c., would be of the least avail against a lock 
 made on this principle. Different kinds of detectors may be 
 applied to these locks. It is submitted that this lock, retain¬ 
 ing all the simplicity and durability which have distinguished 
 Chubb’s lock for so many years, and combining with them 
 these important improvements, affords a complete security 
 against all surreptitious attempts of any nature. Locks on 
 the same principle are being made on the permutation plan, 
 with any number of tumblers, and any number of changes in 
 combination that may be desired. 
 
 “ It has been suggested that the ‘ detector,’ instead of giving 
 additional security to Chubb’s lock, affords a partial guidance 
 to a person attempting to pick it. This objection holds good 
 to a certain extent in these locks as originally made, in which 
 all the tumblers had gn equal bearing against the detector- 
 stump ; but in the locks as now constructed this objection is 
 entirely obviated, by giving the tumblers an unequal bearing, 
 whereby, if an operator feels the obstruction of the detector- 
 stump, he cannot tell whether the tumbler which he is lifting 
 is raised too high, or not high enough. 
 
 “ Lock No. 3.—For banks, Mr. Chubb has introduced what 
 he particularly calls his ‘ bank lock.’ It contains a barrel with 
 a series of curtains. While the key-hole is open, all access to 
 the tumblers from the key-hole is completely cut off by two 
 sliding pieces of solid metal, which fit closely on either side of 
 the barrel. These pieces are acted upon by an eccentric mo¬ 
 tion, so that when the key is applied to the lock, and turned 
 in it, the key-hole is shut up by the revolution of the curtains, 
 and then only do the sliding pieces of metal move aside to allow 
 the key to act upon the tumblers. These pieces return to their 
 position when the key has passed ; therefore, while the key is 
 lifting the tumblers, all communication is cut off from the ex¬ 
 terior of the lock by these sliding pieces and the series of 
 curtains. The bolt is made in two pieces, the main bolt never 
 being in contact with the key, which acts only on the talon- 
 bolt, and by it transmits the motion to the main bolt. After 
 
150 
 
 ON LOCKS. 
 
 the action of locking, the talon-bolt is partly repelled, and a 
 lever or ‘ dog’ connected with it locks into a series of combina¬ 
 tions arranged upon the front parts of the tumblers, and holds 
 them securely down, so that none of them can be lifted in the 
 least degree until the talon-bolt is thrown forward to release 
 them. If, therefore, any pressure be applied to this talon-bolt, 
 to endeavour by its help to ascertain the combinations of the 
 tumblers, it will only the more tightly lock them down, and 
 render the attempt ineffectual. By another contrivance it is 
 rendered impracticable to move a pick or picks round in the 
 lock more than a small distance, unless the tumblers could 
 previously be all lifted to their right positions, which can only 
 be done by the right key. Should one or more of the tumblers 
 be surreptitiously raised by any possible means, they cannot 
 be detained in this uplifted position, for the action of turning 
 back the pick to try to raise another tumbler sets in motion a 
 lever which allows the tumblers already raised to drop to their 
 former position, leaving the operator just as far from the attain¬ 
 ment of his object as at the outset.” 
 
 Such is the statement with which Messrs. Chubb have fa¬ 
 voured us respecting their three new locks. We are willing to 
 admit the enterprising spirit which has led to their production, 
 and the ingenuity which has been bestowed on their construc¬ 
 tion ; but whether they mark a step in advance in the art of 
 lock-making may perhaps admit of doubt. With respect to 
 the lock No. 1, we would remark, that locks rvith the barrel 
 and curtain combined were made by Mr. Aubin of Wolver¬ 
 hampton in 1833, and that a specimen of such a lock was 
 exhibited on his stand of locks in the Great Exhibition. 
 Locks with the combined barrel and curtain were also made 
 and sold by Mr. Jones of Newark, N. J., as stated at p. 104. 
 
 With respect to the lock No. 2, the object of the tumbler- 
 bolt is evidently intended to produce the same effect as the 
 movable stump in Mr. Hobbs’s p>ro tec tor-lock, fig. 47, page 100; 
 but with greater complexity in the construction, there is less 
 efficiency in the action of this part of Mr. Chubb’s lock as 
 
ME. CHUBB’S NEW LOCKS. 
 
 151 
 
 compared with that of Mr. Hobbs, inasmuch as a pres¬ 
 sure of the stump against the tumblers, corresponding with 
 the strength of the spring which holds the bolt in its place, 
 can always be produced, thereby giving friction, and affording 
 indication as to which tumbler it is that is in tight contact with 
 the stump. 
 
 With respect to the barrel and curtains of lock No. 3, and 
 all similar contrivances, the object of which is said to be to 
 prevent the entrance into the key-hole of all instruments ex¬ 
 cept the proper key, we would offer the self-evident remark, 
 that the same aperture which admits the key will also admit 
 some other instrument. In the case of Mr. Chubb’s “ bank- 
 lock,” it may be questioned whether the revolving curtain, &c. 
 give it any advantage over the other locks already referred to 
 which are furnished with similar contrivances. The effect of 
 the talon-bolt in this lock appears to be the same as that of the 
 false notches, namely, to hold the tumblers in the position in 
 which they were placed when the pressure was applied. Hence, 
 a pressure applied to the talon-bolt affects the parts which 
 come in contact with the key in the act of locking and unlock¬ 
 ing; and this circumstance brings the lock under the applica¬ 
 tion of the principle stated at page 99, and thus, if this prin¬ 
 ciple be admitted, may render the security of the lock somewhat 
 questionable. 
 
 Various other locks have been brought out since the date 
 of the “lock controversy” in the year 1851. We would gladly 
 notice them all, did they shew novelty of design and mark an 
 advance in the art of the locksmith. We must, however, ad¬ 
 mire the ingenuity with which Mr. Hobbs’s movable stump 
 has been more or less adopted; but in the attempts to imitate 
 it the objection has not been removed, that it is possible to 
 produce on the tumblers a pressure or friction equal to the 
 strength of the spring which holds the tumblers down. 
 
 There is, however, a lock which has lately been introduced 
 to the public, which calls for special notice, on account of the 
 high honours which have been bestowed upon it. We refer to 
 
152 
 
 ON LOCKS. 
 
 the prize lock of the Society of Arts, London, the invention of 
 Mr. H. J. Saxby of Slieerness, who has received the Society’s 
 medal and the sum of ten guineas as the reward of his ingenu¬ 
 ity. The interior of this lock consists of a cylinder with four 
 pins or slides radiating from the centre, and pressed into the 
 key-hole by means of spiral springs. The pins project beyond 
 the periphery of the wheel or cylinder, and into slots in a ring 
 which is affixed to the case of the lock, thereby preventing the 
 cylinder from being turned. On each pin is a notch, so placed 
 that when the proper key is inserted into the key-hole, the 
 notches on the several pins will be brought into a position 
 such as will allow the cylinder to turn. The turning of the 
 cylinder in this, as in the Bramah lock, shoots the bolt. 
 
 A lock on precisely the same principle, but more secure in 
 its construction, was described by Mr. Hobbs in a paper read 
 by him before the Society of Arts in January 1852, when dia¬ 
 grams illustrative of the same were exhibited. This paper was 
 not reported at any length in the journal of the Society’s pro¬ 
 ceedings; but the same paper was read by Mr. Hobbs, March 1, 
 1852, before the Liverpool Polytechnic Society, and a full re¬ 
 port thereof, and a description of the lock in question, is given 
 in the “ Transactions” of that Society, from September 1849 
 to December 1852 (8vo, Liverpool, 1853). This lock is no 
 other than the Yale lock already noticed at page 83, and is 
 thus described at page 196 of the “ Transactions:” 
 
 “ Another description of cylinder-lock was invented, a few 
 years since, by a Mr. Yale of the State of New York, U.S.A. 
 
 “ The Yale lock has two cylinders, one working within the 
 other; and they are held together by a series of pins reaching 
 through the cylinders into the key-hole, which is in the centre. 
 On the back of the inner cylinder is a pin that fits into a slot 
 in the bolt, and moves it as the cylinder is turned. The pins 
 that hold the cylinders together and prevent the inner one 
 from turning, are cut in two at different lengths. The key 
 is so made, that by inserting it into the key-hole the pins 
 are moved, so that the joint in the pins meets the joint be- 
 
THE SOCIETY OF ARTS PRIZE LOCK. 
 
 153 
 
 tween the cylinders, and allows the inner one to be turned. 
 But, as with the slides of the Bramah lock, should any one of 
 the pins be pushed too far, the cylinder is held quite as firmly 
 as though it had not been touched. Some of these locks have 
 been made with as many as forty pins; and to a person un¬ 
 acquainted with the principles on which locks are picked, they 
 would seem to present an insurmountable barrier. 
 
 “ Figure 1* represents the case of the lock containing the 
 bolt A, having a groove b, to receive the pin c on the cylinder. 
 Figure 2 shews the cap or top-plate of the lock, and the cylin¬ 
 ders ; d d is the outer cylinder, that is stationary, being fastened 
 to the plate; e e the inner or moving cylinder; f f the four 
 rows of pins, being cut in two at different lengths, and reach¬ 
 ing through the cylinders into the key-hole; g G are the springs 
 that press the pins to their places; c the pin that fits into the 
 groove and moves the bolt. Figure 3 is an end view of the 
 key, shewing four grooves. Figure 4 is a side view, shewing 
 the irregular surface of the grooves by which the pins are 
 adjusted. 
 
 “ For the purpose of picking the lock, an instrument is made 
 that will fit between two of the pins; to that is attached a lever 
 and weight, thereby getting a pressure on the cylinder and 
 causing the pins to* bind; then with another instrument the 
 pins are felt, and as they are found to bind, they are pressed 
 in until they are relieved (as they will be when the joint comes 
 to the right place), thereby easily opening the lock. There is 
 a great similarity in the operation and security of this and the 
 lock manufactured by Mr. Cotterill of Birmingham.” 
 
 In the Society of Arts Journal for the 24th June, 1853, is 
 a letter from Mr. Hobbs on the subject of the prize lock, which, 
 it appears, he picked, “ in the presence of parties connected 
 with the Society, in the short space of three minutes.” 
 
 * This and the following figures refer to the diagrams exhibited by Mr. 
 Hobbs. 
 
154 
 
 ON LOCKS. 
 
 CHAPTER XL 
 
 THE LOCK AND KEY MANUFACTURE. 
 
 The manufacture of locks and keys, considered as a depart¬ 
 ment of working in iron, is one that requires, and indeed 
 admits of, very little description. The hammer, the file, the 
 drill, the fly-press, are the chief instruments employed; the 
 iron itself being brought to something like the desired state 
 and form by rolling or casting, or both. But the manufacture 
 is interesting in its social features—in its relation to the persons 
 employed and the buildings occupied. One by one, several 
 departments of industry have progressed /rom the handicraft 
 to the factory system — from that system in which a man and 
 a few apprentices work in a small shop in the lockmaker’s 
 garret or kitchen, to that in which organisation is maintained 
 among twenty or fifty or a hundred men. Locks have scarcely 
 yet passed out of the first stage, but there is no good reason 
 whatever why they should so remain; there are as many rea¬ 
 sons for progress in this as in other arts, and indications are 
 not wanting that some such progress will be made. 
 
 So far as England is concerned, the neighbourhood of 
 Wolverhampton is the great storehouse whence locks are ob¬ 
 tained. Eminent lock-makers reside in London and in other 
 principal towns; but Wolverhampton is regarded by all as the 
 centre of the trade. This is not a modern localisation, for 
 we have information respecting the locks of Wolverhampton a 
 century and a quarter ago. Among the Harleian Manuscripts 
 is an account of “ The Voyage of Don Manuel Gonzales (late 
 merchant), of the City of Lisbon in Portugal, to Great Britain: 
 containing an Historical, Geographical, Topographical, Poli¬ 
 tical, and Ecclesiastical Account of England and Scotland; 
 with a Curious Collection of things particularly rare, both in 
 Nature and Antiquity.” This Ms. appears to have been writ- 
 
THE LOCK AND KEY MANUFACTUBE. 
 
 155 
 
 ten about 1732; it was translated from the Portuguese, and 
 printed in Pinkerton’s Collection of Voyages and Travels. 
 'With reference to Wolverhampton, Gonzales says: “ The chief 
 manufacturers of this town are locksmiths, who are reckoned 
 the most expert of that trade in England. They are so curiotis 
 in this art, that they can contrive a lock so that if a servant 
 be sent into the closet with the master-key, or their own, it 
 will shew how many times that servant hath gone in at any 
 distance of time, and how many times the lock has been shot 
 for a whole year; seme of them being made to discover five 
 hundred or a thousand times. We are informed also that 
 a very fine lock was made in this town, sold for 20 1., which 
 had a set of chimes in it that would go at any hour the owner 
 should think fit.” If Gonzales were correct in these descrip¬ 
 tions, they indicate an exercise of considerable ingenuity in 
 lock-construction, especially in reference to the lock which 
 keeps a registry of the number of times it has been opened. 
 There is abundant evidence that the old lock-makers were 
 very fond of these knick-knack locks, which would do all 
 sorts of strange and unexpected things; and this may in part 
 account for the great favour in which locks have been held by 
 amateur machinists. 
 
 The lock-manufacture in South Staffordshire is of a re¬ 
 markable character, comprised as it is within so small an area. 
 Although Wolverhampton is known commercially as the chief 
 depot of the English lock trade, yet it is at Willenhall, three 
 or four miles eastward of that town, that the actual manufac¬ 
 ture is chiefly carried on. When the Commission was ap¬ 
 pointed a few years ago to inquire into the condition of children 
 employed in trades and manufactures, Mr. E. Id. Horne was 
 deputed to examine the Wolverhampton district; and his re¬ 
 port is too curious, and too closely connected with our present 
 subject, to be passed unnoticed. We here give an abstract of 
 such parts of his report as bear reference to the lock-makers 
 of Willenhall. 
 
 Almost the entire industry of Willenhall is in the three 
 
15G 
 
 ON LOCKS. 
 
 articles of currycombs, locks and keys, and articles connected 
 incidentally with locks, such as bolts and latches. At the 
 time Mr. Horne wrote, in 1841, there were among the master 
 manufacturers 268 locksmiths, 76 key-makers, 14 bolt-makers, 
 and 13 latch-makers; besides many small masters living in 
 such out-of-the-way corners that they escaped enumeration. 
 In the Post-Office Directory of that district, of later date, there 
 are entries of rather a curious character. In the first place it 
 is observable that different kinds of locks are made by differ¬ 
 ent persons, each manufacturer confining his operations appa¬ 
 rently to one kind of lock; one is a rim-loch maker, another a 
 trunk-lock maker, a third a cabinet-loch maker, a fourth a pad¬ 
 lock maker, a fifth a mortice-lock maker, and so on. But a 
 much more singular feature is, that lock-making is combined 
 with retail dealing of a totally different kind; thus among the 
 occupations put down opposite the names of individuals are, 
 “ key-stamper and beer-retailer,” “ door-lock maker and beer- 
 retailer,” “ grocer and trunk-lock maker,” “ Malt-Shovel ta¬ 
 vern-keeper and rim-lock maker,” “ lock-maker and provision- 
 dealer,” “ grocer and key-maker,” “ cabinet-lock maker and 
 Woolpack tavern,” “key-stamper and registrar of births, &c.,” 
 “ Hope and Anchor and cabinet-lock maker,” “ auctioneer and 
 locksmith,” “ rim-lock and varnish maker,” and so forth. It 
 is probable that in some of these cases the wife attends to the 
 retail shop, while the husband attends to the workshop. 
 
 Among all the lock-manufacturers of the town there are 
 scarcely half a dozen in what may be termed a large way of 
 business; there are many who employ from five to fifteen pairs 
 of hands, but the great majority are small masters who are 
 themselyes working mechanics, and are aided by apprentices 
 from one to four in number, perhaps two on an average. Mr. 
 Horne thinks that there were not fewer than a thousand boys 
 at work in the town, chiefly upon locks and keys. The chil¬ 
 dren and young persons are employed at all ages, from seven 
 up to manhood; from the earliest age, indeed, in which they 
 are able to hold a file. It is a characteristic fact, where so 
 
THE LOCK AND KEY MANUFACTURE. 
 
 157 
 
 many of the male inhabitants are employed at the bench from 
 such early years, that a certain distortion of figure is observa¬ 
 ble; the right shoulder-blade becomes displaced and projects, 
 and the right leg crooks and bends inwards at the knee, like 
 the letter K,—it is the leg which is hindermost in standing 
 at the vice. The right hand also has frequently a marked dis¬ 
 tortion. “ Almost every thing it holds takes the position of the 
 file. If the poor man carries a limp lettuce or a limper mack- 
 arel from Wolverhampton market, they are never dangled, but 
 always held like the file. If he carry nothing, his right hand 
 is in just the same position.” 
 
 The hours of labour among the small masters are scarcely 
 brought within any system at all; for all the work is piece¬ 
 work, not paid for by the day or hour; and each man works 
 as long as he likes, or as long as his business impels him. 
 Some will file away from four or five in the morning till eleven 
 or twelve at night. In the larger shops, where there are many 
 hands employed, they come to work when they like, leave 
 when they like, and do as much work as they like when there; 
 this freedom of action being spread over a working-day of 
 perhaps sixteen hours. The masters say that the men prefer 
 this system, or want of system, to any thing more precise and 
 regular. In the beginning of the week there is often much 
 idleness and holiday-keeping; and the Willenhall men make 
 up for this by a day of sixteen, eighteen, or even twenty hours’ 
 work towards the end of the week. In the beginning of the 
 week, men and boys have defined hours and definite periods 
 for meals; but towards the end of the week, when hurry and 
 drive are the order of the day, they eat their meals while at 
 work, and bolt their victuals standing. “ You see a locksmith 
 and his two apprentices, with a plate before each of them, 
 heaped up (at the best of times, when they can get such 
 things) with potatoes and lumps of something or other, but 
 seldom meat, and a large slice of bread in one hand; your 
 attention is called off for two minutes, and on turning round 
 again, you see the man and boys filing at the vice.” 
 
153 
 
 ON LOCKS. 
 
 In the processes as carried on at Willenhall, they are ap¬ 
 plied chiefly to the manufacture of mortice, box, trunk, rim, 
 cabinet, case, bright, dead, closet, and padlocks. Except some 
 of the parts of the brass-work, which are cast , these locks are 
 made by forging, pressing, and filing. The forging is a light kind 
 of smith’s work, aided by a light hammer and a small pair of 
 bellows; children and young persons are largely employed in 
 this process. Pressing is a kind of work by which certain 
 parts of the lock are pressed or stamped out. The presses are 
 of various sizes, but all require much strength to work them; 
 the press has a horizontal lever, crossing the top of a vertical 
 screw, and there is generally an iron weight at the end of each 
 arm or half of the lever to increase the power; one of the lever 
 arms is grasped in the right hand of the presser, and whirled 
 round with a jerk; while the fingers of the left hand place the 
 metal in its proper position, and remove it when it has been 
 stamped or pressed. There is, of course, a die or cutter 
 attached to the press, to cut the metal in the proper form. 
 Sometimes the press has only one arm to the lever, and no 
 weight at the end of this, so that the labour of working is 
 much increased. Children and youths are employed at this 
 process, so far as their strength will admit. The last process, 
 filing, is that by which the separate pieces are shaped and 
 smoothed for adjustment in their proper places; here children 
 and youths are almost exclusively employed; they stand upon 
 blocks so as to be able to reach the vice, and then work away 
 with the file, unrelieved by any change in the nature of the 
 process. 
 
 In key-making the processes may be said to comprise 
 forging, stamping, piercing, and filing. The forging differs very 
 little from that required in making the pieces for a lock. The 
 stamping is effected by placing the end of an iron wire, taken 
 red-hot from the forge, into one half of a key-mould made in 
 a block or kind of anvil; a heavy weight is then raised be¬ 
 tween an upright framework, in the grooves of which it runs 
 by means of a cord; the cord is drawn by both hands, with 
 
THE LOCK AND KEY MANUFACTURE. 
 
 159 
 
 the assistance of one foot in a stirrup attached to the end of 
 the cord; at the bottom of the weight thus raised is the other 
 half of the key-mould. Such being the nature of the stamp¬ 
 ing apparatus, the process is thus conducted: the foot in the 
 stirrup being suddenly raised, and the cord loosed, the weight 
 falls upon the red-hot wire, and the blow stamps it into the 
 two moulds or half-moulds, which are brought accurately to¬ 
 gether by means of the slides or side-grooves in the frame¬ 
 work. The rough key is also trimmed and cleared by the 
 pressing apparatus; that is, the surplus metal all round is 
 cut off by a single blow; and the metal which fills up the ring 
 or handle of the key is cut or pressed out in the same way. 
 This is a heavy part of the key-work, for which the labour of 
 men rather than that of boys is required. The process of 
 'piercing the key consists in making the pipe or barrel, required 
 for most keys, except those Avhich are intended to open a lock 
 for both sides; the pipe is drilled by a small machine worked 
 with the foot like a lathe; it is a process requiring more skill 
 than strength, relatively to other parts of the manufacture. 
 Th q filing of a key is important; for not only is the whole key 
 made bright, but the wards are cut by the file and chisel. 
 Boys and youths are employed in filing the common keys; but 
 those of better quality are entrusted to men. 
 
 The apprenticeship system is carried on to a remarkable 
 extent among the look and key makers of Willenhall. The 
 small masters take apprentices at any age at which they can 
 work. Some of them employ only apprentices, never paying- 
 wages for journeymen, but always taking on a new apprentice 
 as soon as a former one is out of his time. The boys are 
 mostly procured from other towns, and they bring with them a 
 small apprenticeship-fee and a suit or two of clothes. They 
 are bound to the masters by legal indenture or contract; and 
 the masters board and lodge and clothe them during their 
 apprenticeship. One consequence of this system is, that when 
 the apprentice has served his time, he is almost driven to be¬ 
 come a small master himself from want of employment as a jour- 
 
160 
 
 a. 
 
 ON LOCKS. 
 
 neyman; and he then takes apprentices as his master did be¬ 
 fore him. This accounts for the fact that in Wiilenhall there 
 are few large manufacturers and few journeymen; while there 
 is a constantly-increasing number of small masters and of ap¬ 
 prentices. 
 
 The Wiilenhall makers nearly all look to the Wolver¬ 
 hampton factors or dealers for a market for their wares—so 
 far at least as concerns locks and keys; there are some other 
 articles which they sell more frequently to Birmingham houses. 
 The master and an apprentice, or perhaps two, generally 
 trudge off to Wolverhampton on a Saturday, bearing the stock 
 of locks which he may have to sell; and the money receipts for 
 the locks or keys sold are usually in part spent at the large 
 market of Wolverhampton previous to the homeward journey. 
 The Wiilenhall men take contracts at so low a price as to pre¬ 
 vent the competition of other places; it is stated, that whatever be 
 prices elsewhere, nothing can come below the Wiilenhall prices 
 for cheap locks. The men work hard for small returns, and yet 
 they have a strong yearning for their own town. A Willen- 
 liall girl will seldom marry except to a townsman; and thus 
 they intermarry to an extent which maintains their character¬ 
 istics as a peculiar community. As an example of their dis¬ 
 inclination to leave their own town, Mr. Horne states the fol¬ 
 lowing circumstance : “ Some years ago a factor, who had 
 projected a manufactory in Brussels, engaged some five-and- 
 twenty Wiilenhall men, whom he was at the expense of taking 
 over. lie gave them all work, and from hard-earned wages 
 of from 9s. to 15s. a-week, these ‘practised hands’ found 
 themselves able to earn 31. a-week and upwards. But they 
 were not satisfied, and began to feel uncomfortable; first one 
 left, and returned home; then another; then one or two; till, 
 in the course of a few weeks, every man had returned to Wii¬ 
 lenhall”—there to work harder and earn less. 
 
 It is just possible that the application of the factory system 
 to lock-making may first become important by making the best 
 locks cheaper than they can be made by the handicraft method ; 
 
THE LOCK AND KEY MANUFACTURE. 
 
 161 
 
 for there seems not much probability, at least for a great length 
 of time to come, that any new system will be able to compete 
 with Willenhall in the common locks—those of which more 
 thousands are sold than there are tens of the better locks. In 
 this, however, it would not do to predict rashly. Hand-loom 
 weaving is cheap enough, unfortunately for those who practise 
 it; but yet the factory system comes down as low as the lowest 
 hand-loom weaving. 
 
 The editor of Hebert’s Encyclopedia, after noticing the 
 facilities for opening most locks by copying the key, makes 
 the following announcement: “ It affords the editor of this 
 work much satisfaction to state, that he has in his possession 
 a lock, the key of which cannot be copied , a locksmith possess¬ 
 ing no tools by which an exactly similar one can be made ; 
 the machine by which the original one was made is so arranged 
 as to be deprived of the power of producing another like it. 
 The lock is very simple, very strong, and can be very cheaply 
 made. The cost of a complete machine to make them would 
 be about 100k ; with that they might be manufactured at one- 
 half the expense of any patent lock. The inventor is desirous 
 to have the subject brought before the public under a patent; 
 but want of time to devote himself to such an object at present 
 obliges him to lay it aside.” The invention not being patented, 
 the editor of course gave no diagram or engraving of the lock 
 or machine ; nor does there appear to have been a patent ob¬ 
 tained during the sixteen or eighteen years which have elapsed 
 since the above notice was published. There are, however, 
 mechanical principles sufficiently well known to lead to a be¬ 
 lief that such a machine is practicable ; a ticket-printing or 
 numbering machine will, in printing 100,000 tickets, produce 
 such variations that no two impressions shall be identical; and 
 a key-making machine might, after fashioning a particular 
 part of each key, modify the arrangement of certain wheels 
 and pinions so far as to produce a slightly different result 
 when the next key is to be operated on. 
 
 In the manufacture of locks and keys generally, there is 
 
162 
 
 ON LOCKS. 
 
 no reason why the factory system should not, to a certain ex¬ 
 tent, be applicable. By this will be understood, the production 
 of similar parts by tools or machines, graduated in respect to 
 each other with more care than can be done by the hand me¬ 
 thod. If we suppose that a lock of particular construction 
 comprises twenty screws and small pieces of metal, and that 
 there are required, for general disposal in the market, five 
 sizes of such a lock ; there would thus be a hundred pieces 
 of metal required for the series, each one differing, either in 
 shape or size, from every one of the others. Now, on the fac- < 
 tory or manufacturing system, as compared with the handicraft 
 system, forging, drawing, casting, stamping, and punching, 
 would supersede much of the tiling ; the drilling machine 
 would supersede the drill-stock and bow, and other machines 
 would supersede other hand-worked tools. This would be i 
 done—not merely because the work could be accomplished 
 more quickly or more cheaply—but because an accuracy of 
 adjustment would be attained, such as no hand-work could 
 equal, unless it be such special work as would command a 
 high rate of payment. For any one size in the series, and 
 any one piece of metal in each size of lock, a standard would 
 be obtained which could be copied to any extent, and all the 
 copies would be like each other. To pursue our illustration, 
 the manufacturer might have a hundred boxes or drawers, 
 and might supply each with a hundred copies of the par¬ 
 ticular piece of metal to which it is appropriated, all so ex¬ 
 actly alike that any one. copy might be taken as well as any 
 other. Ten pieces, one from each of ten of these boxes, would 
 together form a lock ; ten, one from each of another ten boxes, 
 would form a second lock, and so on ; and there would be, in 
 the whole of the boxes, materials for a thousand locks of one 
 construction, a hundred of each size. 
 
 Noav the advantage of the machine or factory mode of 
 producing such articles is this, that they can be made in 
 large numbers at one time, whenever the steam-engine is at • 
 work ; and that when so made, the pieces are shaped so exactly 
 
THE LOCK AND KEY MANUFACTURE. 
 
 163 
 
 alike, the screws have threads so identical, and the holes are 
 bored so equal in diameter, that any one of a hundred copies 
 would act precisely like all the others, thereby giving great 
 advantages to the men employed in putting the lock together. 
 
 These principles are being applied by Messrs. Hobbs and 
 Co. in their London establishment. A number of machines, 
 worked by steam-power, are employed in shaping the seve¬ 
 ral pieces of metal contained in a lock ; and all the se¬ 
 veral pieces are deposited in labelled compartments, one 
 to each kind of piece. The machines are employed — in 
 some cases to do coarse work, which they can accomplish 
 more quickly than it can be done by men ; and in other cases 
 to do delicate work, which they can accomplish more ac¬ 
 curately than men ; but so far is this from converting the 
 men into lowly-paid automatons (as some might suppose), 
 that the manufacturers are better able to pay good wages for 
 the handicraft labour necessary in putting the locks together, 
 than for forming the separate parts by hand ; just as the 
 11 watchmaker,” as he is called, who puts the separate parts 
 of the watch together, is a better-paid mechanic than the man 
 who is engaged in fabricating any particular parts of the 
 watch. 
 
 It may be observed that the system of manufacturing on a 
 large scale, by many men engaged in one large building, is 
 more nearly universal in the United States than in England. 
 The workshop system, as pursued at Willenliall by the lock- 
 makers, is very little practised in America. Being compara¬ 
 tively a new community, and being at liberty to select for 
 imitation or for improvement whichever of the usages or sys¬ 
 tems in the old country they may prefer, the Americans have 
 preferred to adopt the factory system rather than the workshop 
 system, and to carry out the former to an extent not yet equalled 
 in England—not yet equalled, we mean, in the number of trades 
 to which it is applied. 
 
164 
 
 ON LOCKS. 
 
 CHAPTER XII. 
 
 ENGLISH PATENTS FOR LOCKS-AUBIN*S LOCK TROPHY. 
 
 We propose to conclude this small work with a few details 
 respecting the various patented inventions in locks, and con¬ 
 cerning Mr. Aubin’s remarkable lock trophy. These two 
 subjects relate to locks in general, rather than to any specified 
 constructions in particular, and can on that account more 
 conveniently be given here than in connexion with any of 
 the foregoing chapters. 
 
 Mr. Chubb, in the appendix to his paper on locks and 
 keys read before the Institution of Civil Engineers, gave a 
 useful list of all the patents taken out in England in relation 
 to this subject, down to the year 1849. We here transcribe 
 this list: 
 
 List of Patents for Lochs and Latches granted since the 
 Establishment of the Patent Laws. 
 
 “ As no complete list of the patents granted for locks from 
 the time of James I. has hitherto been published, it is be¬ 
 lieved that the following list, which has been very carefully 
 drawn up, and which comprises all patents from the year 1774, 
 when the first patent for a lock was granted, to the present 
 time, will be found useful as a reference for all wdio are inte- 
 
 rested 
 
 in the subject. 
 
 1774 
 
 May 
 
 27 
 
 1778 
 
 May 
 
 29 
 
 1779 
 
 May 
 
 28 
 
 1780 
 
 March 
 
 4 
 
 1782 
 
 J anuary 
 
 18 
 
 1784 
 
 July 
 
 
 1789 
 
 7 
 
 Black, George, Berwick-on-Tweed. 
 
 Barron, Robert, London. 
 
 Martin, Joshua Lover, Fleet-street, London. 
 Henry, Solomon, Swithin’s-lane, London. 
 Campion, J. Newcastle-eourt, Strand, London. 
 Hutchinson, Samuel, Marylebone, London. 
 Bramah, Joseph, Piccadilly, London. 
 
 Cornthwaite, Thomas, Kendal, Westmoreland. 
 
ENGLISH PATENTS FOR LOCKS. 
 
 165 
 
 February 
 
 23 
 
 October 
 
 29 
 
 July 
 
 19 
 
 November 
 
 3 
 
 November 18 
 
 May 
 
 3 
 
 December 
 
 8 
 
 April 
 
 11 
 
 February 
 
 10 
 
 June 
 
 24 
 
 May 
 
 18 
 
 December 29 
 
 March 
 
 7 
 
 May 
 
 14 
 
 February 
 
 8 
 
 February 
 
 3 
 
 October 
 
 18 
 
 April 
 
 11 
 
 December 
 
 14 
 
 July 
 
 10 
 
 November 13 
 
 June 
 
 15 
 
 May 
 
 14 
 
 May 
 
 17 
 
 June 
 
 1 
 
 J anuary 
 
 18 
 
 January 
 
 26 
 
 April 
 
 14 
 
 May 
 
 23 
 
 July 
 
 27 
 
 December 20 
 
 December 
 
 3 
 
 December 
 
 20 
 
 September 
 
 6 
 
 October 
 
 11 
 
 March 
 
 18 
 
 December 16 
 
 February 
 
 10 
 
 June 
 
 30 
 
 November 13 
 
 February 
 
 21 
 
 June 
 
 12 
 
 July 
 
 3 
 
 July 
 
 20 
 
 August 
 
 1 
 
 December 
 
 2 
 
 February 
 
 27 
 
 March 
 
 20 
 
 May 
 
 2 
 
 June 
 
 13 
 
 October 
 
 22 
 
 December 23 
 
 March 
 
 29 
 
 Rowntree, Thoipas, Surrey-street, Blackfriars, 
 London. 
 
 Bird, Moses, Wardour-street, London. 
 Ferryman, Rev. Robert, Gloucester. 
 
 Antis, John, Fulneck, near Leeds. 
 
 Langton, Daniel. 
 
 Bramah, Joseph. 
 
 Turner, Thomas. 
 
 Davis, George. 
 
 Scott, Richard, Lieut.-Colonel. 
 
 Holemberg, Samuel, London. 
 
 Roux, Albert, Switzerland. 
 
 Stansbury, Abraham Ogier, New York. 
 Thompson, William, Birmingham. 
 
 Mitchell, William, Glasgow ; and Lawton, John, 
 London. 
 
 Ruxton, Thomas, Esq., Dublin. 
 
 Clark, William, Esq., Bath. 
 
 Chubb, Jeremiah, Portsea. 
 
 Strutt, Anthony Radford, Mackeney. 
 
 Jennings, Henry Constantine, Esq., Middlesex, 
 Mallett, William, Dublin. 
 
 Fairbanks, Stephen, Middlesex. 
 
 Ward, John, Middlesex. 
 
 Chubb, Charles, Portsea. 
 
 Young, John, Wolverhampton. 
 
 Chubb, Charles, London. 
 
 Gottlieb, Andrew, Middlesex. 
 
 Carpenter, James, and Young, John, Wolver¬ 
 hampton. 
 
 Arnold, John, Sheffield. 
 
 Rutherford, William, Jedburgh, N.B. 
 
 Barnard, George, Bristol. 
 
 Young, John, Wolverhampton. 
 
 Parsons, Thomas, London. 
 
 Parsons, T., Newport, Salop. 
 
 Chubb, Charles, London ; and Hunter, E., 
 W olverha mpton. 
 
 Longfield, William, Otley. 
 
 Audley, Lord Baron Stafford. 
 
 Hill, R., Birmingham. 
 
 Warwick, J., London. 
 
 Fenton, Rev. S., Pembroke. 
 
 Uzielli, M., London. 
 
 Thompson, S., London. 
 
 Uzielli, M., London. 
 
 Sanders, J. Stafford. 
 
 Cochrane, A., Strand, London. 
 
 Schwieso, J. C., London. 
 
 Williams, W. M., London. 
 
 Guest, J., jun., Birmingham. 
 
 Williams, W. M., London. 
 
 Gerish, F. W. 
 
 Pearse, W., Hoxton, Middlesex. 
 
 Wolverson, J., and Rawlett, W., Stafford. 
 Clark, T. 
 
 Baillie, B., London. 
 
 Tildesley and Sanders, Willenhall and Wolver¬ 
 hampton. 
 
166 
 
 ON LOCKS. 
 
 1841 
 
 9 9 
 f 9 
 
 1842 
 
 9 9 
 
 1843 
 
 May 6 
 
 July 14 
 September 28 
 November 9 
 January 15 
 May 24 
 June 13 
 December 29 
 November 25 
 
 1844 
 
 July 30 
 
 1845 April 15 
 
 , , July 12 
 
 , , December 4 
 
 , , December 22 
 
 1846 July 6 
 
 July 15 
 December 14 
 January 11 
 
 , , April 15 
 
 1848 September 28 
 
 1849 May 8 
 
 Hancock, James, Sidney-square, Mile End. 
 Berry, Miles, Chancery-lane. 
 
 Strong, Theodore Frederick, Goswell-road. 
 Smith, Jesse, Wolverhampton. 
 
 Poole, Moses, Lincoln’s-inn. 
 
 Duce, Joseph, Wolverhampton. 
 
 Williams, W. M., 163 Fenehurch-street. 
 
 Rock, Joseph, jun., Birmingham. 
 
 Tann, E. E. and J., Hackney-road. 
 
 Rock, Joseph, jun., Birmingham. 
 
 Fletcher, Rev. William, Moreton House, Buck¬ 
 ingham. 
 
 Carter, George, Willenhall. 
 
 Ratcliff, Edmund, Birmingham. 
 
 Poole, Moses, Lincoln’s-inn. 
 
 Smith, Philip, High-street, Lambeth. 
 
 De la Fons, John Palmer, Carleton-hill, St. 
 John’s Wood. 
 
 Thomas, William, Cheapside. 
 
 Chubb, John, St. Paul’s Churchyard. 
 
 Chubb, John, and Hunter, Ebenezer, sen., St. 
 Paul's Churchyard. 
 
 Collett, Charles 'Minors, 62 Chancery-lane. 
 Newall, Robert Stirling, Gateshead. 
 
 Wilkes, Samuel, Wednesbury-heath, Wolver¬ 
 hampton. 
 
 Mr. Chubb also gave a list of such papers in the Transac¬ 
 tions of the Society of Arts as refer to locks and keys. 
 
 List of References to the “ Transactions of the Society of Arts'' 
 on the subject of Lochs. 
 
 vol. 
 
 page. 
 
 
 vol. 
 
 page. 
 
 
 
 1 . 
 
 317 
 
 Mr. Moore. 
 
 38. 
 
 Ill 
 
 Mr. 
 
 A. Ainger. 
 
 2. 
 
 187 
 
 ,, Cornthwaite. 
 
 
 205 
 
 )) 
 
 Bramah. 
 
 3. 
 
 160 
 
 Marquis of Worcester. 
 
 42. 
 
 125 
 
 
 J. Duce. 
 
 99 
 
 165 
 
 Mr. Taylor. 
 
 43. 
 
 114 
 
 9 9 
 
 W. Friend. 
 
 18. 
 
 163 
 
 ,, Marshall. 
 
 45. 
 
 123 
 
 
 Machin. 
 
 239 
 
 ,, T. Arkwright. 
 
 48. 
 
 132 
 
 yy 
 
 S. Mordan. 
 
 19. 
 
 243 
 
 ,, Bullock. 
 
 50. 
 
 86 
 
 y9 
 
 A. Mackinnon. 
 
 290 
 
 ,, W. Bullock. 
 
 51. 
 
 128 
 
 
 J. Meighan. 
 
 36. 
 
 111 
 
 ,, M. Somerford. 
 
 
 
 
 
 
 Among 
 
 the most curious mechanical productions in the 
 
 Great Exhibition of 1851, was one which attracted very little 
 notice, viz. that forwarded by Mr. C. Aubin of Wolverhampton. 
 Whether it was that attention, so far as regards locks, was too 
 much absorbed by the “ lock controversy,” or whether there 
 was a deficiency of descriptive cataloguing, no juror or news¬ 
 paper critic, as far as we are aware, took notice of the produc¬ 
 tion in question. In the Official Illustrated Catalogue it is 
 entered simply as “ Specimens to illustrate the rise and pro- 
 
aubin’s lock trophy. 
 
 167 
 
 ' gress of the art of making locks, containing forty-four different 
 movements by the most celebrated inventors in the lock trade.” 
 This trophy of lock ingenuity (for such it may be justly con¬ 
 sidered to be) is now in the possession of Mr. Hobbs. Spring¬ 
 ing from a hexagonal base-piece is a central axis, about three 
 feet in height, supporting four horizontal circular discs, placed 
 at different parts of its height. Each of the vertical faces of 
 the base-piece contains a lock, which is worked by its respec¬ 
 tive key. Each disc contains a number of locks: 16 on the 
 lowest, 12 on the next above, 9 on the third in height, while a 
 Bramah lock surmounts the whole. All the locks on the discs 
 are so arranged that their bolts shoot outwards, or radially away 
 from the axis of the machine. Every lock has its own proper 
 key inserted in the key-hole; and as the locks lie down horizon¬ 
 tally, the shaft of each key is of course vertical. There are deli¬ 
 cate pieces of mechanism contained within the central axis and 
 within the discs, consisting of levers, racks, and pinions ; and 
 the Bramah lock is contrived so ingeniously, that the Bramah 
 key, by acting upon that lock, acts upon all this mechanism. 
 The Bramah barrel, in rotating horizontally under the action of 
 its key, gives a rotary movement to a rod passing vertically 
 through the centre of the whole apparatus; this rod, at the levels 
 of the several discs, acts upon racks and pinions, and these in 
 turn act upon the key-pins of the several locks. When, there¬ 
 fore, the Bramah key is turned, the whole of these key-pins 
 rotate, each exactly in the same way as if the lock were being 
 closed or opened, and the bolts shoot in or out accordingly. 
 The Bramah key, although it acts as a master-key, is not such 
 as usually obtains that designation ; it is simply a means of 
 putting in action certain rack-and-pinion mechanism, which 
 does not belong to lock-work considered per se. All the locks 
 are faithful representatives of the several patents or modes of 
 construction to which they severally refer ; and each exhibits 
 the works sufficiently open to display the principle on which 
 it is arranged. Each lock is numbered, and is referred to in 
 an accompanying description. The works are finished with 
 
1G8 
 
 ON LOCKS. 
 
 tlie utmost care and polish; and the trophy being somewhat 
 tastefully arranged, and kept under a glass shade, forms a really 
 elegant specimen of mechanical skill. 
 
 For an account of the locks themselves which constitute 
 this trophy, we cannot do better than avail ourselves of the 
 description given in the article “ Lock” in Tomlinson’s Cyclo¬ 
 paedia of Useful Arts, adding a few further details in respect 
 to some of the locks of the series. The locks are arranged 
 and numbered according to their similarity of construction; 
 and it is instructive to remark the evidence here afforded, 
 that many patentees would have saved much time and money 
 if they had better known the productions of their predecessors. 
 In describing these locks we shall do so briefly, sufficient to 
 shew their relative principles of construction; many of them 
 having been described more or less fully in former chapters. 
 
 No. 1 on the list is called a Roman lock; it consists of a 
 single bolt, with a binder-spring for holding the bolt in any 
 position in which it may be placed until a sufficient force is i 
 applied to overcome it: it embodies the simple principle on 
 which thousands of common locks are annually made. 
 
 No. 2, called a French lock (all such designations are of rather 1 
 doubtful correctness), resembling No. 1 in every thing except 
 having the addition of a friction-roller. The bolt of either of 
 these two locks can easily be forced back by pressing on the end. 
 
 No. 3 is marked Ancient; it is a bolt-lock, and was found 
 in an ancient building. It exhibits an improvement on both 
 the former specimens, in so far as the bolt requires, before it : 
 can be shot, to be pressed down, in order to release it from a 
 catch at the back end of the bolt; this release cannot be 
 effected without the aid of a key or some other implement 
 applied through the key-hole, and thus the bolt answers the 
 purpose both of bolt and tumbler. 
 
 No. 4, also marked Ancient, is in principle a single-acting 
 tumbler-lock ; that is, one in which the tumbler may fail to 
 be lifted high enough, but cannot be raised too high, to release 
 the bolt: whereas a double-acting tumbler, being susceptible 
 
attbin’s lock trophy. 
 
 169 
 
 both, of too much and too little ascent, must be raised to one 
 definite and precise height to attain the required obj ect. 
 
 Ho. 5, an old English loch, exhibits a great advance in 
 principle, being provided with the double action just described 
 as being wanting in Ho. 4. 
 
 No. 6, modern English (no maker’s name), is a single-acting 
 tumbler-lock. 
 
 Ho. 7, by Mace , is a double-acting tumbler, but without 
 exhibiting any peculiarities of construction. 
 
 Ho. 8 is Somerford's first patent. It is a double-acting draw 
 tumbler-lock ; that is, there is a tumbler which is drawn down 
 instead of being lifted, as in most locks. 
 
 Ho. 9, designated, we know not on what grounds, an Indian 
 lock, has a single-acting tumbler with a pin. 
 
 Ho. 10, patented by Thompson in 1805. In this lock 
 there are two tumblers, one of which is single and the other 
 double-acting. 
 
 Hext follow a considerable number of locks, which differ 
 one from another too slightly to render any formal description 
 necessary. Ho. 11, by Baniells, is a single-acting tumbler, 
 differing only in form from those previously used. Ho. 12 is 
 by Walton. Ho. 13 is Barron’s first patent, taken out in 1771. 
 Ho. 14 is by Bicherton. Ho. 15 is a Butch lock. Ho. 16 is 
 by Buce , senior. Ho. 17, by Sanders, is a lock with four 
 double-acting tumblers. Ho. 18, patented by Cornthwaite in 
 1789, is so nearly like Sanders’s, brought before public notice 
 in 1839, as to corroborate what we have said concerning the 
 identity, or at least close resemblance, of inventions widely 
 asunder in point of time. Ho. 19 is by Richards and Peers. 
 
 Ho. 20 is Somerford's second patent; a lock which seems 
 to embody the principle of Mr. Tann’s “ reliance-wards,” pa¬ 
 tented many years later. Ho. 21 is Rowntree's lock, patented 
 in 1790. Ho. 22 is the first patent lock of Buce , junior, dated 
 1823. Ho. 23 is Parsons' first patent, of 1832. Ho. 24 is 
 Bicherton's second. Ho. 25, patented by Price in 1774; this, 
 so far as at present appears, was the first lock ever constructed 
 
 i 
 
170 
 
 OK LOCKS. 
 
 with four double-acting tumblers, bearing a closer resemblance 
 than would generally be supposed to those patented by other 
 persons in more recent years. No. 26 exhibits a somewhat 
 similar coincidence. It was introduced by Aubin in 1830, and 
 is furnished with a revolving curtain for the purpose of closing 
 the key-hole during the revolution of the key. Other inven¬ 
 tors have since then adopted the revolving curtain; and in a 
 patent taken out so recently as 1852, this appendage is claimed 
 as part of the patent. 
 
 No. 27 is Barron's second patent, dated 1778 ; a lock which 
 has perhaps been the model for a larger manufacture of plain 
 simple tumbler-locks than any other. No. 28 is by Bird , 1790. 
 No. 29 is the second patent of Puce, junior. No. 30 is 
 Buxton's, 1818. No. 31 is Chubb’s simplified lock, 1834. 
 No. 32 is by Marr. No. 33, by Tann, is the “ reliance-ward ” 
 lock adverted to above as having been anticipated, in respect 
 to its leading principle, by Somerford’s second patent. No. 34 
 is by Hunter, 1833. No. 35 is Parsons’ second patent, of the 
 same year. No. 36 is by Lang, 1830. No. 37 is Lawton’s, 
 dated 1815. No. 38, patented by Strutt in 1839, has an 
 arrangement for holding the tumblers, in the event of a 
 pressure being applied to the bolt; an arrangement bearing 
 a considerable resemblance to one recently adopted in Chubb’s 
 bankers’ lock. No. 39 is by Scott, 1815. No. 40, Chubb’s 
 patent of 1818, is the original detector-lock of this maker. 
 Most of the detectors since patented by various persons are 
 little other than variations of Chubb’s original. 
 
 No. 41, Parsons’ third patent of 1833, is a changeable lock 
 of peculiar construction. The elevation of the tumblers is 
 regulated by an adjusting-screw passing through the lock to 
 the inside of the door; this screw changes the positive but 
 not the relative positions of the tumblers ; so that the same 
 difference in the steps of the key must be retained, the 
 change being made only in the length of the bit: the number 
 of changes for each lock is very limited. 
 
 No. 42, invented by Pierce in 1840, seems to be a carrying 
 
ATTBtN S LOCK TROPHY. 
 
 171 
 
 out of the plan suggested by the Marquis of "Worcester in his 
 Century of Inventions , where he says that “ a lock may be so 
 constructed that if a stranger attempteth to open it, it catches 
 his hand as a trap catcheth a fox ; though far from maiming 
 him for life, yet marketh him so, that if once suspected he 
 might easily be detected.” In Pierce’s lock a steel barb or 
 sharp arrow-head is concealed below the key-hole, in such a 
 manner that if any person in attempting to open the lock 
 should over-lift the tumbler, the barb would be thrust by a 
 spring into his hand. It is said that the patentee himself 
 i experienced the efficacy of this invention, by receiving the 
 barb into his own hand. 
 
 Ho. 43, by Ruxton, patented in 1816, is furnished with a 
 tell-tale, so arranged that if the tumbler be over-lifted in an 
 attempt to pick the lock, a pin or catch is thrown out from 
 the lock, which would be visible on opening the lock with 
 the proper key. This invention preceded Chubb’s detector 
 by two years, and would be entitled to some of the honours 
 of originality were not Chubb’s arrangement much more 
 simple and effective. 
 
 Ho. 44 is Bramah's , the patent of 1784, and the crowning 
 lock of the trophy, by which all the others are opened. Si¬ 
 milar locks by Russell and Mordan are applications of the 
 Bramah principle, with "little or no variation. 
 
 Ho attempt has been made in these pages to describe every 
 variety of lock that has been introduced. Several forms of 
 puzzle locks, known as Russian and Chinese locks, have the 
 forms of various animals, and they are locked and unlocked 
 by pressing upon or moving some portion of the body of the 
 animal: the security of such locks depends in many cases 
 upon keeping the part to be pressed or moved secret. There 
 are also various forms of alarum locks; but these do not 
 greatly differ from common locks, except in having certain 
 appendages, such as a pistol, which if loaded and properly 
 adjusted, will be fired on any attempt being made to open 
 
 i 2 
 
172 
 
 ON LOCKS. 
 
 the lock, either with its own key or some other instrument. 
 Some locks are furnished with a bell or a rattle, which is 
 rung or sprung on attempting to open the lock, and in this 
 way the inmates of the house are informed of the attempt to 
 effect an entrance. It will, however, be evident to any one 
 who has read the preceding pages, that devices of this kind 
 do not add to the security of the lock ; they rather tend to 
 degrade the art of the locksmith to that of the toyman. The 
 locksmith, in common with eveiy other artist, can only im¬ 
 prove in his art by studying the principles upon which it 
 rests, and illustrating them by the most approved examples 
 which the constructive genius of his predecessors or contem¬ 
 poraries has furnished. 
 
APPENDIX. 
 
 CHAPTER XIII. 
 
 ON AN IMPROVED CONSTRUCTION OF LOCK AND KEY.* 
 
 The simple fixed-guard or warded lock is so utterly worthless 
 for security, no matter what amount of good workmanship he 
 bestowed upon it, that it demands but short notice. It was 
 contrived with the intention of making the passage to the 
 bolt intricate; but it will be seen at once that this intricacy 
 does not really offer any security. The wards of a lock are 
 circular arcs of thin metal, so arranged as to require a key of 
 peculiar pattern to pass amongst them, the shape of the cuts 
 in the key being a section of the wards. To make a really 
 complicated box of wards, and to cut keys which shall ac¬ 
 curately fit their sweep, is a matter requiring considerable 
 manual dexterity; and some warded locks are therefore ex¬ 
 pensive. But even with the best of them, all that it is neces¬ 
 sary to do for opening the lock is to take a blank key which 
 will properly fit the keyhole, coat it with wax, and then in¬ 
 serting it in the lock, press it round against the wards, which 
 will cause them to leave an accurate impression of their 
 section on the key. The parts impressed are then cut out 
 with small files, drills, and saws, and the occasional use of 
 fine cross-cut chisels. The key will then pass those wards 
 which impressed themselves upon it; and if these are the 
 
 * By J. Beverley Fenby, Mechanical Engineer, of Birmingham. 
 Extracted chiefly from the Proceedings of the Institution of Mecha¬ 
 nical Engineers, 1866. 
 
174 
 
 ON LOCKS. 
 
 only wards, it will go completely round and open the lock. : 
 If there are also other wards in addition, not brought up : 
 flush with the first wards, the key is waxed again and pressed *j 
 against them, and then further cut out, as before. This • 
 process is evidently one of absolute certainty, and the key so 
 made is in all respects as capable of mastering the lock as 
 the original key. 
 
 These warded locks are however easily opened with merely 
 a piece of bent steel wire,—bent into such a sweep as will 
 reach right round the wards instead of passing amongst 
 them, thus escaping all chance of being obstructed by them. 
 Such an instrument is called by burglars a “ twirl.” 
 
 The fixed-guard or warded lock was the one in general use 
 in the middle ages. 
 
 The next kind of lock is the tumbler lock, in which the 
 holt is moved backwards and forwards by the key as usual, 
 but these movements cannot take place till a small lever with 
 a stump on one side he lifted. This lever and stump form 
 the tumbler, which is held down by a spring; and in the 
 tail of the bolt are two notches, into one of which the stump 
 tits when the bolt is shot, and into the other when it is with¬ 
 drawn. All that is necessary to effect the picking of this 
 lock is to lift the tumbler high enough for clearing the 
 stump out of the notch, and then draw hack the bolt. The 
 tumbler may be lifted with one pick, and the holt drawn 
 back with another; but generally one pick will suffice for 
 both purposes. 
 
 In the Barron tumbler lock the principle of double-action 
 was introduced. 
 
 The next improvement was the lever lock properly so called, 
 under which designation the majority of the modern locks 
 may be classed. 
 
 The Bramah lock was an admirable contrivance with re¬ 
 markably beautiful mechanism contained in a small compass; 
 and since its invention there have been several ingenious 
 modifications of the same principle in different radial locks, 
 
APPENDIX. 
 
 175 
 
 such as the Tale lock, in which the slides move radially 
 instead of axially. One advantage in these radial locks is 
 the greater difficulty in copying the keys, in comparison with 
 the flat keys of ordinary lever locks : this difficulty however 
 is not an insurmountable one. 
 
 A very ingenious addition was made to the action of the 
 lever lock in Newell’s American lock, which was shown in 
 the 1851 Exhibition, and described at page 89 of the present 
 volume. 
 
 Though locks such as those already referred to exhibit 
 great dissimilarity of construction, yet there is one point in 
 which they all agree, and that is in the possession of a direct 
 passage from the outside to the works. Although various 
 locks have been devised with the object of having no direct 
 passage to the works from the outside, one consideration 
 shows the inevitable existence of such a passage; namely, 
 that without it the key could not possibly at one and the 
 same time touch the hand of the operator and the works of 
 the lock. It therefore follows that any instrument which 
 can pass in the same space as the key may be brought to 
 bear on the works, whatever may be their construction. 
 
 It can now be shown that, if picking instruments are thus 
 brought to bear on the works through the keyhole, there is a 
 regular tentative system whereby the picking of any lock 
 with an open keyhole can sooner or later be effected. 
 
 From the foregoing observations it is evident that there 
 are two important defects in the principle of the previous 
 lever locks, which being defects in principle are fatal to their 
 security; namely, the means of access to the works of the 
 lock through the keyhole, allowing of a series of attempts 
 being made to open the lock by picking instruments; and 
 also the facility afforded for repeating the trial of a false key 
 made from a wax impression of the true key, and thus per¬ 
 fecting it by successive alterations after trial. In conse¬ 
 quence of the possibility thus allowed of making these suc¬ 
 cessive attempts either by picking instruments or by a false 
 
176 
 
 ON LOCKS. 
 
 key, it has been shown by the cases that hare occurred of 
 locks of the best makes which have been falsely opened, that, 
 however numerous and complicated may be the secondary 
 impediments introduced into these locks, there can be no real 
 security against the ultimate success of sufficiently numerous 
 and persevering attempts, except by the adoption of some new 
 principle of construction specially meeting the above two 
 defects. 
 
 In the invention of the Improved Lock and Key now to be 
 described, and which has been termed the adytic lock,* the 
 
 writer’s object has been to meet this requirement. In fig. 53 
 is shown an elevation of this lock, such as is made for an iron 
 safe ; two of the front cover plates being removed to show the 
 construction. 
 
 The head b of the main bolt is of such a thickness as to be 
 flush with the face of the levers l and guard a ; and the 
 
 From the Greek clSvtoq, inaccessible. 
 
APPENDIX. 
 
 177 
 
 strap or tail d of the bolt is thin, and passes behind the levers 
 and guard, and also behind the plate h n. The part of the 
 tail d which would lie under the levers i and cylinder c is 
 removed, as seen in fig. 54, and replaced by a separate flat 
 plate or stump-bolt, carrying the stump s. This stump- 
 bolt has a projection k upon it, let into a recess in the tail d 
 of the main bolt, but with T yth inch vertical play in the re¬ 
 cess. A spring in the tail of the main bolt presses the stump- 
 
 bolt downwards, keeping the stump s in the notches of the 
 levers i, as shown in fig. 53. The stump-bolt can thus descend 
 J^th inch at first without moving the main bolt, and this 
 amount of vertical movement is sufficient to carry the stump 
 in and out of the notches in the levers ; but the stump-bolt 
 cannot descend further without taking the main bolt with it. 
 
 Immediately in front of the bolts comes the fixed plate h h, 
 in which is cut the cam groove shown by the dotted line j j ; 
 and also the vertical slot e for the pin p to work through, 
 together with another vertical slot in which the stump s fits 
 and works. This plate carries the centre pin u on which the 
 levers l turn. The levers are six in number, though any 
 
 i 3 
 
178 
 
 OX LOCKS. 
 
 other number may be used; and they occupy collectively 
 ftbs inch thickness. In front of the plate h is fixed the 
 guard a, which is made of iron or steel, 
 and has the brass cylinder c ground into it. 
 The guard is made a shade thicker than 
 the levers l, in order to prevent the back 
 plate h and the corresponding front plate 
 from being so tightened on the levers as 
 to impede their freedom of movement. The 
 cylinder c is the same thickness as the 
 levers, excepting the centre boss f, which 
 projects from the back of the cylinder and 
 works in a hearing in the hack plate h, and 
 also projects in front through the thickness 
 of the two front cover plates. The small 
 keyhole in the centre of the boss goes only 
 a short distance into the cylinder c, being 
 merely for the purpose of enabling the 
 stem of the key m, fig. 55, to turn the 
 cylinder; the bit of the key is a separate 
 piece, x, fig. 57, which is inserted through 
 a separate keyhole into the radial slot of 
 the revolving cylinder c, as shown at x in 
 fig. 53. 
 
 This radial slot is cut in *ne side of the cylinder c that is 
 furthest from the levers when the cylinder is in the position 
 shown in fig. 53; and in the slot fits the slide block k, which 
 is a steel block having a pin projecting on each side. The 
 hack pin enters the guide groove j j in the hack plate h, as 
 shown by the dotted line, and the front pin enters the cor¬ 
 responding guide groove in the front cover plate, which is 
 shown removed. The back pin of the slide block projects 
 through the hack plate n, as shown in fig. 56, and works in 
 the cam groove o in the tail of the stump-holt s, fig. 54, which 
 is so shaped that as the slide block travels round the guide 
 groove j j , shown by the dotted lines, it moves the stump-holt 
 
 fig. 55. 
 
APPENDIX. 
 
 179 
 
 vertically as may be required according to the position of the 
 bolts and levers. 
 
 In tbe position of tbe lock shown in fig. 53, the bit n has 
 been inserted into the vacant space of the radial slot in the 
 cylinder c, in front of the slide block n. The size of this 
 vacant space is ^ths inch long by jth inch wide and f ths 
 
 fig. 56. 
 
 inch deep; and in the two front cover plates of the lock, 
 and also in the door to which the lock is attached, a hole 
 is made of the same shape. In the door there is no bearing 
 ; for the centre boss f, but only a small keyhole correspond¬ 
 ing in size with that in the boss f for inserting the stem of 
 the key. 
 
 In the position of the parts shown in fig. 53, it will be seen 
 that the levers l are held pressing down against the circum¬ 
 ference of the cylinder c by their springs i bearing against the 
 pin p. In this position also the bolt spring between the main 
 bolt and the stump-bolt, fig. 54, presses the stump s down into 
 the notches of the levers, so that the levers are completely 
 locked by the stump, as seen in fig. 53. 
 
 In order to unlock the lock, which in fig. 53 is shown with 
 the bolt shot, it is necessary that all the gatings g in the 
 levers should be brought precisely under the stump s. 
 Through the centre keyhole f there is no communication 
 possible at any time with the levers l ; nor will any instru¬ 
 ment, however slender, if passed into the radial slot through 
 the aperture at n be able to reach them, whether the cylinder 
 c be in the position shown in fig. 53 or turned round into any 
 
180 
 
 ON LOCKS. 
 
 other position. For the only difference made by turning the 
 solid cylinder c is that the radial slot in it is carried away 
 from the aperture in the external plates, and the solid part of 
 the cylinder is brought opposite to the aperture, which is 
 thereby completely closed against the insertion of a picking 
 instrument. This construction accordingly not only precludes 
 the possibility of opening this lock with an ordinary key, in 
 which the part that acts on the levers is attached to the stem 
 of the key, but it also renders it an absolute impossibility to 
 introduce a pick of any form, as nothing can reach the levers 
 l except a detached piece of such a size and shape as to be 
 capable of travelling round in the vacant space left in front of 
 the slide block r in the radial slot of the cylinder c. 
 
 For the purpose of unlocking the lock the bit n, fig. 57, is 
 used. This bit is of such a size as to fit into the 
 vacant space of f X | X §- inch in the radial slot of 
 the cylinder c; and the indent at v is merely for 
 the purpose of ensuring the insertion of the bit in 
 the right direction, the external aperture for the 
 bit being made with a corresponding projection 
 to fit the indent in the bit. This bit being inserted 
 through the aperture in the door, is pushed in by means 
 of the key stem m, which is flattened on two sides for that 
 purpose, as shown in fig. 55 ; and the bit is thus pushed 
 home into its place in the radial slot of the cylinder, as 
 shown at n, fig. 53. 
 
 The key stem m is now inserted into the centre keyhole r, 
 and the cylinder is turned round by it in the direction shown 
 by the arrow, carrying round the slide block r and the bit s. 
 The slide block r, while moving through the concentric portion 
 at the commencement of the guide grooves j j, does not affect 
 the bit; but by means of the cam groove o in the tail of the 
 stump-bolt, fig. 54, it moves that bolt so far as to lift the stump 
 s completely out of the notches in the levers l, which are 
 thereby left free to be raised. On continuing to turn the 
 cylinder c, the eccentric part of the guide grooves j j causes 
 
APPENDIX. 
 
 181 
 
 the slide block k to move outwards along the radial slot, 
 pushing the bit n before it; and the hit is thus made to pro¬ 
 ject beyond the circumference of the cylinder, which it can 
 then do, being no longer confined by the guard a. The further 
 projection of the bit as the cylinder revolves causes the steps 
 in the bit to lift their respective levers; and the steps in the 
 bit are so arranged that, when the cylinder arrives at the 
 
 position shown in fig. 58, all the gatings <j are brought simul¬ 
 taneously opposite the stump s, which is instantly shot down 
 through the distance of the x^th inch play by the bolt spring. 
 The bit n remains in contact with the extreme part t of the 
 levers while the stump s is entering the gatings, the action of 
 the bolt spring being so rapid that the bit cannot move 
 through any appreciable distance during the time. 
 
 In other locks a spring action of this kind would greatly 
 facilitate the picking, inasmuch as it would afford the gentle 
 uniform pressure desired upon the levers. In other locks, 
 therefore, the bolt is caused to move, and the stump to 
 
182 
 
 ON LOCKS. 
 
 enter the gatings, by the direct contact of the key with 
 the holt, instead of by a spring; but as the key, while 
 moving the stump into the gatings, is also altering its 
 position under the levers, a slight tremulous motion of the 
 levers is thereby occasioned, which no care in manufacture 
 can obviate. This tremulous motion is aggravated by the 
 circumstance that, as the keyhole is open to inspection, it is 
 necessary to make all the levers fit flush with one another when 
 down, in order to avoid affording any clue to the shape of the 
 key from the positions of the levers; but as the various steps 
 of the key, being of different lengths, describe different arcs, 
 the curves of the levers when raised are of necessity in error 
 to them all. The result of these combined faults is that the 
 gatings have to be made wider than the stump, to allow a 
 sufficient amount of play, thus introducing a fatal element of 
 insecurity in the construction of the lock, since the security 
 is of course enhanced in proportion as the gatings fit the 
 stump accurately. In the new lock, on the contrary, the arc 
 t, fig. 58, in each lever, can be shaped truly to its own proper 
 radius, independent of all the rest of the levers ; and as the 
 action of the stump is instantaneous in catching the gatings 
 as soon as they are all brought simultaneously under it, the 
 stump and gatings can be made to fit one another with the 
 most perfect accuracy, and without the slightest play. 
 
 On turning the cylinder c further round, the bit n passes 
 from under the levers, which remain held back by the inser¬ 
 tion of the stump in the gatings; and just before reaching 
 the position shown in fig. 59, the slide block n has pushed 
 the bit completely out of the radial slot, and the bit falls 
 down as shown in fig. 59, and drops through a hole into the 
 inside of the safe that is locked. At this point the back pin 
 of the slide block comes in contact with the lower side of the 
 cam groove o in the stump-bolt, fig. 54 ; and by turning the 
 cylinder c onwards to the position shown in fig. 60, the with¬ 
 drawal of the bolt b is completed, bringing the parts into the 
 position shown in fig. 60. In these drawings only one lever 
 
APPENDIX. 
 
 183 
 
 l is shown; but there are altogether six levers, as shown in 
 the sectional plan, fig. 56. The pin p is fixed in the tail n of 
 
 the main bolt, so as to travel with the bolt; and by this 
 means the springs i are released from strain, as shown in 
 fig. 60, as soon as the bolt is withdrawn. 
 
 From the nicety with which the various parts of this lock 
 are constructed, it is evident that the levers must he very 
 accurately lifted by the bit of the key in order to withdraw 
 the holt; and therefore any error in the bit, such as would 
 occur with a false bit, will effectually prevent the lock from 
 being opened. This may he illustrated by supposing the 
 false bit to he so close an imitation as to have five of its steps 
 absolutely correct, and the sixth only slightly wrong : though 
 it is almost impossible that such a near approach to correct¬ 
 ness could he attained in practice. The counterfeit bit being 
 inserted in the lock, and the cylinder turned round, all will 
 go on the same as with the true bit, up to the time when the 
 
184 
 
 oy LOCKS. 
 
 false bit reaches the point t of the levers, as previously shown 
 with the true bit in fig. 58. Here a change of action takes 
 place ; but what is the nature of the change the operator has 
 no means as yet of ascertaining. In the case supposed, where 
 five of the steps in the bit are right, but the sixth is wrong, the 
 gating of the sixth lever does not precisely coincide with the 
 others, nor with the stump s; and the consequence is that, at 
 
 fig. 60. 
 
 the critical moment when the stump ought to spring into the 
 gatings and hold back the levers from falling forwards, it will 
 be prevented from entering the gatings, owing to the entrance 
 being partly blocked up by the one lever, which stands more 
 or less across it. 
 
 The fact, however, that the stump cannot enter the gatings, 
 does not become known to the operator until the cylinder c 
 has been turned further round, so as to bring the slide-block 
 pin in contact with the lower side of the cam groove o in the 
 stump-bolt; and before this point has been reached the false 
 bit has already passed clear of the levers, which, not being 
 retained by the stump, are instantly thrown forwards again 
 by their springs, and locked in their original position by the 
 
APPENDIX. 
 
 185 
 
 stump entering the notches. At the same time the false hit 
 has dropped into the inside of the safe in the same manner as 
 the true bit, as shown in fig. 61. 
 
 Hence a person putting a false bit into one of these locks 
 
 fig. 61. 
 
 will not only infallibly lose it at the very first trial, but will 
 do so without gaining any information as to the nature of its 
 inaccuracy; for as the gatings of the levers cannot be seen or 
 felt, all that can be told about the action of a false bit is, 
 that it has failed to open the lock. In fact, a counterfeit bit 
 passes under the levers, and through the lock, just like the 
 true bit; and it is only the stoppage afterwards met with of 
 the bolt that indicates the failure of the false bit, which is 
 by that time gone beyond recovery. Whatever amount of 
 labour, therefore, may have been spent on the fabrication of a 
 counterfeit bit, this bit can only be tried once, so that no 
 alteration can afterwards be made in it. 
 
 Nothing that can be inserted into the radial slot of the 
 cylinder c through the aperture in the front plates can do 
 any injury to the lock ; and a charge of gunpowder inserted in 
 
186 
 
 ON LOCKS. 
 
 that way would only blow out again at the orifice without 
 
 fig. 62. 
 
 1 
 
 damaging the lock, both the apertures for the key being 
 merely blind holes with parallel sides. 
 
 fig. 63. 
 
 of a small circular saw 
 
 For the manufacture of the 
 bits for the keys of this lock 
 a self-acting machine is em¬ 
 ployed, in which the height 
 and width of the several steps 
 in the bit are regulated by 
 adjustments of very great ac¬ 
 curacy, and admitting of an 
 almost endless variety of figure 
 for the bits. This key-cut¬ 
 ting machine is shown in 
 figs. 62 to 64, and consists 
 a running vertically, of the same 
 
APPENDIX. 
 
 187 
 
 thickness as each step in the bit i, which is brought up 
 to the saw by the slide-rest b. The bit i is fixed in the 
 
 fig. 64. 
 
 holder c, which rocks upon a centre, so as to give the required 
 curvature to the edge of each step in the bit when cut by 
 
188 
 
 ON LOCKS. 
 
 the saw, as shown in the full-size section of the hit-holder, ; 
 fig. 63. The adjustment of the depth of cut is effected by the • 
 set screw d upon the slide-rest coming up against the eccentric 
 ring e upon the bed of the slide-rest; this ring is turned 
 round by hand, and set to sixteen different positions by means 
 of the catch-pin r and the sixteen holes on the circumference 
 of the ring, allowing of sixteen different depths of cut. The 
 lateral adjustment for the pitch between the successive steps 
 of the bit is effected by the two bed-screws g g acting on the 
 slide-rest b, having a dividing plate on the head, and such a 
 pitch of thread that one turn of the screws traverses the slide- ; 
 rest through the exact distance of one step in the bit. The 
 occurrence of any play or backlash is entirely prevented by 
 having the screws placed one at each end of the slide-rest; so 
 that by slacking back one screw through one or more turns, 
 and then advancing the other through the same number of 
 turns, the slide-rest is always held with perfect steadiness 
 between them, filling exactly the space between the ends of I 
 the two screws. 
 
 The number of changes admissible in this key-cutting 
 machine, if used for making keys for locks having six levers, j 
 is the number of permutations that sixteen terms are capable 
 of when taken six together, which is upwards of sixteen 
 millions. Some of these changes are so slight that too great 
 accuracy of workmanship would be required to make the 
 locks accordingly; but of those changes that differ from one 
 another so far that no lock could be opened by any other than 
 its own key, more remain than could be used up by all the 
 locks in the world. 
 
 The writer may observe that it was the study of the cir¬ 
 cumstances of the great gold robbery on the 15th of May, 
 1855, by Agar and his confederates (when two of the best 
 lever locks were picked, and gold stolen weighing upwards 
 of 200 lbs., while in transit on the South-Eastern Railway 
 from London to Paris, packed in three sealed iron-bound 
 boxes, inclosed in a bullion safe, secured by those locks), 
 
APPENDIX. 
 
 189 
 
 and of the various modes of picking locks, which led him to 
 turn his attention to the achievement of what had been so 
 long and perseveringly sought after, namely, an unpickable 
 lock. The principle of a detached bit has been previously 
 tried, in so far as that locks have been made in which the bit of 
 the key was deposited in the lock by unscrewing the key stem, 
 and then withdrawn by screwing in the stem again. But 
 inasmuch as the detached bit, even though it failed to open 
 the lock in the case of a counterfeit key, could always be 
 brought back again to the keyhole and removed, this admitted 
 of a repetition of attempts with successive alterations of the 
 one counterfeit key, without the certainty that any warning 
 would be given by, the lock of such attempts having been 
 made. 
 
 In another still more complicated lock with a detached bit 
 there were two keyholes, into one of which the bit of the key 
 was put, and the stem being then unscrewed from the bit, 
 was put into the second keyhole and turned round so as to close 
 the first keyhole over the bit; a separate handle was then 
 turned to work the lock, six separate operations being re¬ 
 quired for either opening or closing the lock. Further, a 
 kind of retainer has been attempted by so arranging the lock 
 that, if any key was put in but the right one, it was held in 
 the keyhole in such a manner that it could never be got out. 
 In this case, however, if the false key would not open the 
 lock, neither would it let even the right one do so, and it 
 would be necessary to break open the door secured by the 
 lock. 
 
 In the new lock here described, the special points that have 
 been aimed at are the following :— 
 
 Firstly, in no position of the lock is there any access to the 
 works from the outside through the keyhole. This access 
 through the keyhole is more or less a defect in all other prin¬ 
 ciples of lock, as it admits of feeling and manipulating the 
 works for the purpose of getting information for picking the 
 
190 
 
 OX LOCKS. 
 
 lock in the absence of the right key; whereas in the new 
 lock there is no opening whatever at any time, except the 
 two plain parallel recesses into which the key and the bit are 
 fitted. From the moment the turning of the lock commences 
 both these recesses are effectually blocked up : the one for the 
 hit being conveyed bodily away from the keyhole, and its 
 place taken by the solid metal of the cylinder; while the 
 other is completely filled by the key, which cannot be with¬ 
 drawn except by turning it hack to the original position. In 
 consequence of this construction no injury can he done to the 
 lock by explosion of gunpowder in the keyhole, the only 
 openings from the outside being parallel at their sides, and 
 not communicating with any portion of the interior of the 
 lock ; and the simplicity and solidity of construction are such 
 that the revolving cylinder is made practically air-tight within 
 its bearing. This effectually prevents all attempts to open 
 the lock by picklocks, and leaves no alternative hut the 
 attempt to make a sufficiently accurate copy of the true key. 
 
 Secondly, as no clue whatever can be obtained from the 
 outside of the lock respecting the key required, the attempts 
 upon the lock are thus limited to the chance of obtaining a 
 wax impression of the true key. The difficulty of making a 
 counterfeit key sufficiently correct by this means for opening 
 one of the best of the previous constructions of lock is very 
 great; hut in the new lock this difficulty is greatly increased 
 by the fact of the levers remaining absolutely stationary while 
 the stump enters the gatings, in consequence of which the 
 gatings are made so close a fit to the stump that an exceed¬ 
 ingly minute error in the lifting of any of the levers is suf¬ 
 ficient to prevent the lock being opened. This extreme 
 delicacy of construction can be carried out practically without 
 objection in the new lock, because there is no possibility of 
 putting a strain from the key upon the stump, so as to cause 
 injury by forcing it at the moment of entering the gatings ; 
 for the only force acting upon the stump at that time is 
 the uniform pressure of its own spring. In addition to this 
 
APPENDIX. 
 
 191 
 
 source of increased safety, there is the still more important 
 circumstance that only a single trial can he made of each 
 counterfeit bit; because, if carried forwards far enough to 
 try its effect in opening the lock by passing the levers, the 
 hit is inevitably lost by falling through the lock and inside 
 the door. Thus not only is all chance prevented of a second 
 trial with the same key, but the bit retained inside the door 
 gives warning of the attempt having been made, and shows 
 how near the counterfeit key has approached to the original. 
 The numerous cases that have occurred of attempts to open 
 locks by counterfeit keys, such as the remarkable instance 
 previously referred to, show that even with the most practised 
 hands it is next to impossible to make from a wax impression 
 a key that will serve for opening a good lock the very first 
 time it is tried; and the striking importance is therefore seen 
 of this arrangement in the new lock, which prevents more 
 than a single attempt being made with a counterfeit. 
 
 Thirdly, another advantage to he named in this lock is that 
 the stem alone of the key is required to lock it, but it can 
 only be unlocked by the complete key. The stem, therefore, 
 can be left by the principal of an establishment for locking up 
 by a subordinate; hut the bit, which is the essential part of the 
 key required for opening the lock, need never be used or seen 
 by any one hut the principal himself. As the hole in the 
 external door-plate for the stem of the key has a notch on 
 one side only to admit the key stem, and the cylinder is pre¬ 
 vented from making a complete revolution, the stem of the 
 key cannot be withdrawn from the lock except when the holt 
 is shot; so that its absence from the keyhole serves as a proof 
 that the bolt is shot. 
 
 Fourthly, one other advantage in this lock is its simplicity 
 and solidity of construction. It contains no more parts than 
 the simpler forms of lever lock having the same number of 
 levers, and the total number of separate pieces in the complete 
 lock is only sixteen. The principle of security, therefore, 
 upon which the new lock is constructed, avoids entirely the 
 
192 
 
 ON LOCKS 
 
 complications and the delicate and minute class of work ren¬ 
 dered necessary in other locks by the use of detectors and the 
 other auxiliary contrivances employed for increasing the diffi¬ 
 culty of picking. 
 
 Mr. Fenby exhibited, at a conversazione of the Institute of 
 Civil Engineers, and at the meeting of Mechanical Engineers, 
 specimens of his adytic lock, and showed its action both with 
 the true key and with counterfeit keys ; and he showed by 
 trial that the counterfeit failed to open the lock, notwith¬ 
 standing that by means of the permutating cutting machine 
 it had been made a much nearer approach to a perfect copy 
 than was practicable in the best handwork from a wax impres¬ 
 sion. He also exhibited the key-cutting machine employed for 
 cutting the bits; and also a set of burglar’s tools employed 
 for drilling into the door of an iron safe sufficiently fo r 
 breaking open or removing the lock, showing that the hold 
 required for giving the cutting pressure upon the powerful 
 drill employed for the purpose was obtained by a steel cross 
 piece inserted into the keyhole and turned at right angles, so 
 as to hold across inside the lock; but in the new lock, as the 
 keyhole had no opening into the lock, and only a slight 
 shoulder on one side, no means were afforded for obtaining 
 the required hold for the drill. 
 
 The following are the salient points of the discussion that 
 followed the reading of his paper :— 
 
 The Chairman remarked that the paper just read gave a 
 very excellent and clear description of the detailed working 
 of the new lock, and he thought this construction of lock was 
 a most valuable one, as affording real security against all 
 fraudulent attempts. He inquired whether there would be 
 any possibility of tampering with the lock by examining it 
 upon the inside of a safe door, whenever the door might 
 happen to be left unlocked.; 
 
 Mr. Fenby replied that there was no means of tampering 
 
THE ADYTIC LOCK. 
 
 193 
 
 with the lock from the inside of the door, as the two keyholes 
 for working the lock were only in the front face of the door, 
 and the lock was all closed np on the inside of the door, 
 excepting the hole through which the bit was allowed to drop 
 out; but this would be useless for the purpose of tampering 
 with the lock, as the bit dropped down a tube leading to the 
 bottom of the door, through which no examination of the lock 
 could be successfully made. 
 
 The Chairman inquired whether there was any provision 
 against the bit being accidentally locked np inside the safe, 
 in which case it appeared the lock could not be opened again. 
 
 Mr. Fenby replied that the owner of the safe must of course 
 be careful after unlocking the safe to take the bit out before 
 locking it again, otherwise there would be no means of open¬ 
 ing the lock afterwards with that key. As a precaution, 
 however, against any such accident, each lock was provided 
 with three bits, all duplicates, one of which would be kept 
 in the pocket for use, while the two others would be pre¬ 
 served in a place of safety for the chance of any such con¬ 
 tingency. Moreover, in most of the safes fitted with these 
 locks, the tube through which the bit dropped had been made 
 of such a length as to carry out the bit on opening the door, 
 dropping it into a small tin tray outside the safe; and by this 
 means the accidental locking in of the right bit was rendered 
 impossible. One of the advantages of the new lock was that 
 the stem of the key was not required to be kept constantly in 
 the possession of the owner, but it might be left in the 
 lock, as the bit alone was the valuable part of the key ; and 
 as the bits were of such small size and convenient shape, a 
 number of them might readily be kept in the pocket by a per¬ 
 son having charge of a number of safes, without the incon¬ 
 venience attending a large bunch of ordinary keys. In the 
 case of an attempt being made to open the lock with a counter¬ 
 feit bit, the advantages of retaining the counterfeit inside the 
 safe were not merely that the person attempting the lock was 
 deprived of his instrument, while the proprietor imrne- 
 
 x 
 
194 
 
 ON LOCKS. 
 
 diately discovered the attempt upon the next occasion of 
 opening the safe; but the retention of the counterfeit itself 
 afforded the means of judging, hy a comparison with the true 
 hit, whether the attempt had been made altogether in the 
 dark as to the actual construction of the lock, or whether it 
 was likely that some clue regarding the true hit had been 
 obtained by means of a wax impression or otherwise. In the 
 latter case the owner of the safe might think it desirable to 
 have the lock taken off, and the arrangement of the levers altered, 
 and a new bit made so as to baffle any further attempts. 
 
 Mr. ~W. S. Longridge observed that the inconvenience that 
 had been alluded to with the new lock, of accidentally locking 
 up the bit inside the safe, was no greater than occurred with 
 an ordinary safe lock if ever the key was accidentally lost; 
 in either case, unless the precaution was taken of keeping a 
 duplicate in reserve, it would of course he necessary to have 
 the safe broken open. 
 
 The Chairman inquired how the ideas had been arrived at 
 of separating the bit from the key, and of preventing all access 
 to the works through the keyhole, and also of retaining the 
 hit inside the door after any attempt at unlocking. 
 
 Mr. Tenby replied that his attention had in the first 
 instance been attracted to the subject of the picking of locks as 
 a mechanical problem, and he had found that there had hither¬ 
 to been no principle iu lockmaking which could effectually 
 baffle persevering attempts at picking. Tor although there 
 were certain complicated constructions of locks, having many 
 points of excellence, they had all yielded in time to the pick¬ 
 ing instrument in clever hands; and it must be remembered 
 that any individual lock when once constructed remained 
 stationary as regarded subsequent improvement, whereas the 
 art of picking that lock was continually progressing towards 
 success, with all previous constructions of locks, and it was 
 clear therefore that the lock must ultimately be defeated. 
 He had been further stimulated in the investigation of this 
 subject by the occurrence of the great gold robbery referred 
 
THE AUYTIC LOCK. 
 
 195 
 
 to at page 188 ; and the circumstance which had struck him 
 most forcibly in connection with that robbery had been that 
 locks of the best make hitherto known had admitted of seven 
 successive trials being made upon them without detection, 
 each trial furnishing the information for further perfecting 
 the counterfeit key, until the locks were at length opened. 
 
 These considerations had led him to the conclusion that two 
 points were established and were required to be kept in view 
 for the construction of any lock that should be really secure 
 against fraudulent attempts. The first point was that wherever 
 a man could get instruments into the lock he could ultimately 
 solve any problem laid before him by the maker of the lock, as 
 the lock when once made could be tried any number of times 
 if an instrument could be got into it at all. Hence he had 
 concluded that it was requisite for all access to the interior to 
 be cut off, so as to preclude all possibility of getting a pick- 
 lock in; and this was accordingly accomplished by adopting 
 the plan of separating the bit from the stem of the key. The 
 second point established was that it was necessary to prevent 
 the possibility of making a succession of trials with the same 
 counterfeit key; and it had then struck him that, if the bit of 
 the key were arranged to drop inside the safe in unlocking, 
 there would be no means of going on gradually improving 
 and touching up the counterfeit from the results of previous 
 trials, as the false bit would be irrecoverably lost in the very 
 first attempt, without furnishing any clue whatever as a guide 
 for alteration in a subsequent trial. The first lock that he 
 had invented for meeting the requirements thus pointed out 
 had been made with a solid block having a tunnel through it, 
 but involving the same principle of retaining the bit of the 
 key and keeping the levers inaccessible from the outside. 
 Subsequently, however, he had abandoned that construction 
 and produced the new lock shown in the drawings, having 
 the revolving barrel with radial slot. 
 
 The Chairman proposed a vote of thanks to Mr. Tenby for 
 his paper, which was passed. 
 
 k 2 
 
196 
 
 ON LOCKS. 
 
 CHAPTER XIV. 
 
 fenby’s patent stop-lock. 
 
 This lock has been designed with a view to doing away 
 with several weak points in the construction of lever locks. 
 
 The introduction of the movable stump by Mr. Hobbs, in 
 order to defeat picking by the tentative method of applying 
 pressure to the bolt, so as to cause binding between the stump 
 and the levers, was a great advance in the art of lock-making. 
 
 The movable stump, as so constructed, was, however, open 
 to this objection, that while sufficiently delicate and certain 
 in its action to render picking very difficult, it was at the 
 same time, through the smallness of its parts—resulting from 
 the confined space available for its action—unsuited to with¬ 
 stand any amount of force applied to push hack the bolt. 
 
 In the lock under notice the stump s is formed in the solid 
 
 on the shorter arm a 1 of a cranked lever or oscillating stop 
 a. This stop a works on the steel pin or centre b, which 
 
fenby’s stof-lock. 
 
 197 
 
 latter has a bearing in both plates of the lock. At the end a 
 of the stop a is a recess formed to fit the corner d of the holt- 
 head. c is a stud limiting the range of a in an upward 
 direction, so that when in its normal position the stop a may 
 just clear the bolt-head, as shown in figs. 65, 66, and 67. The 
 tail of the holt, instead of being in the form usually adopted, 
 is formed of the bar e set on edge so as to reach from the back 
 to the front plate of the lock, completely dividing the lower 
 part, in which the keyhole lies, from the upper, in which the 
 main parts of the works are placed. 
 
 This bar e works between the guide pieces g g, so that in 
 whatever position the holt may be, the division of the lock 
 into two chambers is complete. At / is the recess in which 
 the key acts to move the holt. The levers l turn upon the 
 pin i formed in the solid of the holt-head. The part of each 
 lever on which the key is to act passes through a slot or 
 recess in e, the parts h and h l of the levers being struck to 
 the arcs of circles, having their centres coincident with that 
 upon which the levers turn at i. 
 
 As it is not possible to lift the levers out of this slot in the 
 bar e, and further, as the levers and bolt move together in a 
 longitudinal direction, the movements necessary to locking 
 and unlocking open no communication between the upper and 
 lower chambers of the lock. 
 
 The springs of the levers are formed out of the solid metal 
 of the levers themselves, and are thus not liable to that dis¬ 
 placement which so often occurs with separate springs, nor 
 to the corrosion by oxidation incidental to steel springs. 
 They are cut round the corner, and down the front of the 
 lever, to gain greater elasticity. 
 
 In fig. 65 the lock is shown with the front plate removed, 
 and the works as they stand when unlocked. Kg. 66 is the 
 same, except that the works are shown locked, and the back 
 plate removed instead of the front. Fig. 67 shows the front 
 view of fig. 66. Fig. 68 shows the result of any attempt to 
 pick the lock by pressure. 
 
198 
 
 ON LOCKS. 
 
 The lock being locked, as shown in figs. 66 and 67, it will 
 
 fig. 67. 
 
 be seen that the stop a just clears the angle d of the bolt-head. 
 
fexby’s stop-lock. 
 
 199 
 
 Further, that the gatings r of the levers l cannot pass the 
 stump s, unless the levers be so lifted as to coincide with each 
 other and the stump. The stop a being held up by a very 
 light pressure from the lever springs, a small force applied to 
 the stump s is sufficient to upset its equilibrium, and bring 
 down its end a 2 upon the bolt-head at <2, as shown in fig. 68. 
 
 This occurs whenever an attempt is made to “ feel ” the stump 
 with the levers; and not only does the stop a free the levers 
 from all pressure, and so preserve them and the stump from 
 injury, and the lock from being picked, but it also forms a 
 strut for securing the bolt: in fact, no violence short of that 
 necessary to shear the pin b can make the bolt yield. 
 
200 
 
 ON LOCKS. 
 
 The drawings show a mortise lock, but the improvements 
 shown are universally applicable in the construction of locks 
 of all kinds. 
 
 Tor the manufacture of these and other locks, and kindred 
 articles, Messrs. J. B. Tenby and Co., engineers of the Liver¬ 
 pool "Works, Birmingham, have put up, from the designs of 
 their managing partner, Mr. J. Beverley Tenby, an experi¬ 
 mental set of machinery, almost entirely self-acting, and 
 calculated to turn out large quantities of the component parts 
 of locks and other articles with extreme accuracy and 
 rapidity, 
 
 The whole set works on the interchangeable system— 
 as already in use for military small arms. It is not, 
 however, to be supposed that, because the parts of the 
 locks are interchangeable, one key will open several locks 
 —such a source of insecurity being guarded against by the 
 permutating key-cutting machines invented by Mr. Tenby. 
 These machines give complete command over the making 
 of keys, whether it be required to make a comparatively 
 unlimited number, all differing from each other, to make 
 a number alike, or to make sets with master keys. 
 
 Atmospheric and hydraulic pressure also plays an important 
 part in shaping many of the parts of the locks. 
 
NOTE UPON IKON SAFES. 
 
 At the conclusion of this work upon locks it will not be out 
 of place to make a few remarks upon the degree of real safety 
 that attaches to what are commonly called “ safes,” and to 
 point out in a common-sense way what are the chief dangers 
 that these may incur from depredators (whether burglars or 
 in times of public anarchy and violence), and what are the 
 main conditions to he relied upon for safety—assuming that, by 
 one or other of the constructions pointed out in the preceding 
 pages, the lock of the safe he such as to be practically unpick- 
 able, and that carelessness shall not have placed the true key 
 in the possession of the thief. 
 
 There can he no doubt upon the mind of any mechanic or 
 engineer, thoroughly acquainted with practical working in 
 metals, that a good deal of what has been brought forward 
 and affirmed, both by safe-makers and by burglars themselves 
 (turned approvers), as to the wonderfully-ingenious devices 
 resorted to by the latter, by which, if we were to believe 
 it all, nothing in the shape of steel or iron can possibly with¬ 
 stand ultimately the redoubtable powers of these people, is 
 simply fiction—imaginary ingenuity utterly impracticable if 
 tried. Such, for example, is the notion of its being possible, 
 by an ounce or two of gunpowder exploded in the interior, to 
 so blow asunder and dislocate the parts of a well-made safe- 
 lock that the holts shall then he easily got loose, or that a 
 steel-plated safe which resists the drill can be softened “ by 
 the blowpipe.” And just as absurd are some of the wonderful 
 pieces of ingenuity by which some of the burglars’ actual 
 devices are supposed to be met and frustrated; as, for example, 
 one for which we believe a patent has been obtained, consist¬ 
 ing in filling-in the hollow space between the inside and out¬ 
 side plates of the safe with cast-iron bullets left loose. These 
 might, no doubt, break a stemmed drill, after that had 
 
 K 3 
 
202 
 
 IRON SATES. 
 
 pierced the outer plate, but could have 'no effect whatever 
 upon a roww^-shanked drill, such as one of the ordinary Ame¬ 
 rican spiral, or teredo-pointed drills. 
 
 That there are some methods of violence still untried, and 
 yet at the command of the burglar who dares to risk a tole¬ 
 rably loud noise of explosive agents, is well known to s kil ful 
 mechanical engineers, and for obvious reasons it would be 
 unwise that we should give any information as to such; but the 
 real practical and too-often effectual methods of the burglar 
 limit themselves almost entirely to the use of the succession 
 of steel wedges, followed by the powerful steel-pointed pinch¬ 
 ing bar, or bars, to the forcing or prizing-screw, and to making 
 more or less way for this by cutting out beforehand by the 
 pin-drill. 
 
 A safe, to be safe, must be so circumstanced or so con¬ 
 structed, or both, that it should be able to resist the best efforts 
 that can be made by these methods for several hours; perhaps 
 we might say as much as thirty to thirty-six hours—viz., 
 from Saturday night to Monday morning. 
 
 Now we hesitate not to say that the unsafeness of “ safes” 
 arises not from any structural difficulty whatever, but almost 
 always from the parsimony and ignorance of those who pur¬ 
 chase and employ them. Safes, like razors, are made to sell, 
 and if the public demand is for cheap safes, such as we see 
 every day advertised in the newspapers, it was sure to have 
 been, and is, met by a supply of things called safes which are 
 utterly unsafe. The great mass of the showy green and gold 
 gewgaws that one sees in the safe-shop windows, with flaming 
 testimonials as to their fire and burglar-proof powers, are 
 simple shams: a genuine safe could not be made at their 
 prices. 
 
 The very first condition to constitute a genuine safe is that 
 it shall have an ample mass of metal—-fie., not of cast-iron, 
 but of wrought-iron, or best of steel, all round it; and espe¬ 
 cially that the margins of metal all round the door shall be 
 of such huge and surplus scantling that no amount of wedg- 
 
IROX SAFES. 
 
 203 
 
 ing, by construction possible, should be able to bend any one 
 side sensibly. The next is that the workmanship of every part 
 of the safe be first-class: not that there be merely a moulded 
 door with a showy lock and a trumpery brass-plate upon it, 
 but that every comer and joint of plate with plate in sides 
 and back be effectually united and jointed in the best manner, 
 and that the fitting of the hardened edges of the door shall be 
 like those of a valve, and not even let a watch-spring be got 
 in between. If these obvious conditions be observed, and that 
 
 Chatwood’s Safes. 
 
 the safe itself be properly posited in the premises, it will he 
 found, even with ordinary forms of construction as to doors 
 and bolts, but with a really unpickable lock, a very hard nut 
 for the best burglar to crack. 
 
 But much more may be effected without any serious in¬ 
 crease of cost. Several forms of safes are now made, the 
 rabbets of the doors of which are so formed that it is almost 
 a physical impossibility to get any wedge, however thin, to 
 drive in between the door and the frame. This is effected in 
 Chatwood’s patent safes (of Bolton and Manchester), as figured 
 above, by making the door rabbets in cross section curvilinear, 
 
204 
 
 IEON SAFES. 
 
 so that even if the fit be not so perfect but that the edges of 
 a very thin wedge can still he inserted, it yet cannot he 
 driven—for, as it goes forward, it must become curved, and 
 if soft, so as thus to bend, the thin steel will not hear the 
 severe strain of driving, hut if hard, it breaks off into short 
 bits close to the entrance. In addition to this Chatwood’s 
 (and we believe other makers’) safes have bolts so constructed, 
 as seen in the figure, that they hook or lock into the holt 
 recesses in the frame in such a manner as to hold the opposite 
 sides of the frame together, so that, independent of its own 
 proper stiffness, it cannot be bent anywhere, unless by tearing 
 asunder the end on the iron bar constituting each cross-holt. 
 The bolts, in fact, not only secure the door (as in ordinary) 
 from opening, hut secure the door and frame together. "With 
 such a safe, if the owner will only provide a proper position 
 for it in his premises, he may rest pretty easy in mind. 
 
 Safes are very commonly stood upon a wooden floor, or made 
 to form part of a wood-framed bookcase, or press, or stand in 
 a recess. Often they are comeatahle all round, and even 
 underneath, with nought hut an inch hoard below them, and 
 almost always they are left with the front door freely and fully 
 exposed, and with ample and convenient room left all round. 
 This for two or three workmen to manipulate the safe as they 
 may. 
 
 How the only real conditions of safety are that the iron safe 
 should he bedded into brickwork set in Portland cement and 
 sand ; or, what is much better, in hard granite or gritstone 
 masonry, bedded in like manner. Without this be done, a 
 fire-proof safe is simply a delusion ; constructed how it may be, 
 it is only a crucible of more or less badly-conducting power, 
 in which, after a time longer or shorter, deeds, bank-notes, 
 documents, &c., will be calcined, and coin or jewellery 
 melted, and gems flawed and destroyed. We say this in the 
 full face of the delusive so-called “ fiery ordeals ” to which 
 many of the so-called double-cased fire-proof safes are alleged 
 to have been for hours exposed. The safe should always he 
 
APPENDIX. 
 
 205 
 
 embedded in masonry, and rest upon that in such a way that 
 it cannot get undermined by either fire or burglars. 
 
 Whenever the premises admit of it, the door of the 
 safe itself should be set back 10 or 12 inches from the face of 
 the wall in which it is embedded, and an outer door, flush 
 with the face of the wall, should be provided of iron, with a 
 good lock ancl multiple bolts. The door of the safe should 
 open to the right ; and if so, the outer door should open to 
 the left; and neither should open more than square to their 
 position when shut. Ho one but a practical workman or 
 engineer can have an adequate notion of the extent to 
 which any mechanical operation upon the door of a safe thus 
 circumstanced is hampered by its being set back into the 
 wall, and with an outer door that even when open, cuts off 
 all ready manual access to the inner door from one side. 
 
 When premises are constructed, as they should be for all 
 banks and bullion merchants, jewellers, &c., having special 
 regard to a safe as an indisputably secure depository, then 
 the safe should be completely iron or steel cased, and em¬ 
 bedded in hard stone masonry (we shall not here go into 
 additional special precautions against the remoter effects of 
 fire), covered in with a strong fire-brick arch, and with 
 nothing but the solid ground below. The door of the safe 
 should only be approachable through an iron or stone-lined 
 passage, just the size of the safe-door, and no more. This 
 should be some feet in length, and have an outer double- 
 cased steel door, or perhaps that and an intermediate iron 
 falling-door or portcullis, between the outer door and the 
 safe-door. With a safe-door so circumstanced, even suppos¬ 
 ing both these outer doors forced and open, it is almost 
 impracticable for even a single workman, however agile or 
 adroit, to perform any mechanical operation whatever upon 
 the door, least of all upon its surrounding rabbates. These 
 are so close to the solid granite walls, starting out at right 
 angles from the rabbate all round, that he has no room to do 
 anything ; and to get a prizing-bar at the door-rabbate, or 
 
 L 
 
206 
 
 ON LOCKS. 
 
 even to get a second man to assist the first in any way, is 
 impossible, simply for want of room. 
 
 The whole of the doors and all the surfaces of such 
 passage should be painted a dull, lustreless black. No one 
 who has not tried it, has any idea of the difficulty of 
 illuminating such a black passage, by even several candles, 
 sufficiently to perform any delicate mechanical operation ; 
 and good light is essential to the safe-breaker. 
 
 In banks there is no better plan than has been ere now 
 adopted of making the iron safe a great cube, with the door 
 at one side, placing the whole safe with its bottom resting 
 upon the stem or plunger of an hydraulic press, the cylinder 
 of which is fixed in the bottom of the pit in the solid earth, 
 of a size capable of enabling the whole safe to be bodily 
 lowered down into the cavity at the end of the day’s work, 
 and pumped up again out of its hiding-place the next morn¬ 
 ing. The lever of the hydraulic pump is taken away, and 
 the socket into which it fits is plugged, and the plug locked 
 into its place, and then the pump—situated in a recess in 
 solid masonry—is itself locked up. The top of the safe itself, 
 when it has been lowered to the bottom of its chamber, 
 stands 10 or 12 inches below the floor-level of the stone floor, 
 and a pair of iron doors is then closed over it and locked down. 
 
 A safe executed in this way, though requiring a consider¬ 
 able expenditure at first, if well done, might bid defiance to 
 anything almost, even unlimited gunpowder, for some days. 
 The only addition of safety that almost could be conceived 
 would be that adopted at the bullion vaults of the Bank of 
 Trance in Paris, where these, situated in casemates two 
 stories under ground, are only approachable by one narrow, 
 winding staircase, which can be itself, in case of emergency, 
 rapidly rendered useless, and the cylindrical well in which it 
 is placed filled up with about 30 feet in depth of water, 
 which cannot be pumped out until a continuous supply be 
 shut off by distant means only known to one or two trusted 
 employes. 
 
APPENDIX. 
 
 207 
 
 Since this revision has been in type the great “ safes’ 
 contest ” or wager of battle between the rival safes of Mr. 
 Herring of Hew York, and Mr. Chatwood of Bolton, for 
 £600 a side, has come off, at the International Exhibition, 
 Paris, Mr. R. Mallet and Mr. Robert E. Eairlie, C.E., 
 being the representatives of the English interests upon 
 the occasion. The result, which, owing to the conduct of 
 some of the parties concerned, assumed an unpleasant and 
 incomplete form, may be found detailed fully in a pamphlet 
 published by Tinsley Brothers, London. It is referred to 
 here because, although no decision of the wager made could 
 be come to, the facts ascertained are of great interest and 
 importance as respects the proper construction of safes. 
 They show conclusively that an effectively constructed door 
 and jambs is really the one thing needful to absolute security, 
 provided the safe itself be built up, as we have urged, into 
 masonry. 
 
 They also show that there are good grounds for doubting 
 that the American (Herring’s) “safe within safe” construc¬ 
 tion, with a thick mass of so-called fire-proofing powdery com¬ 
 position between them, is at all as protective against mere 
 violence and the persevering use of wedges, as Chatwood’s 
 simpler but far more effective construction, especially of his 
 door and jambs. If one of the latter safes, wholly of steel 
 plating, be fairly embedded into masonry, and another out¬ 
 side flush door of his construction, with curved rabbates 
 and hooking locking bolts, be supplied to the masonry ope 
 itself, it is scarcely an exaggeration to call such a safe 
 “ Invincible,” so far as anything that burglars, in any civi¬ 
 lised place in Europe at least, can effect. 
 
INDEX. 
 
 Adytic lock, 176 ; machine for ma¬ 
 nufacturing the keys of the, 185 , 
 number of changes in the lock, 
 188; advantages of, 189; dis¬ 
 cussion on its value, 192. 
 
 Ainger on the Bramah lock. 111. 
 
 Ainger’s lock, 61. 
 
 Alarum lock, 40. 
 
 American locks, 82; Stansbury’s 
 lock, 83; Yale’s lock, 83; Br. 
 Andrews’s lock, 84; Day and 
 Newell’s locks, 86 ; their Parau- 
 toptic lock, 89 ; Hobbs’s Protec¬ 
 tor lock, 99. 
 
 Ancient locks, 8. 
 
 Andrews’s lock, 84; snail wheel 
 lock, 85. 
 
 Appendix, 173. 
 
 Aubiu’s lock trophy, 166; locks 
 forming it described, 168. 
 
 Barron’s tumbler lock, 49; Bra¬ 
 mah on, 68. 
 
 Bird’s tumbler lock, 52. 
 
 Bramah on Barron’s tumbler lock, 
 68; on the defects of the tum¬ 
 bler lock, 68; on the defects of 
 the warded lock, 66. 
 
 Bramah lock, 70; cylinder lock, 
 73; number of changes in the 
 Bramah lock, 81 ; picked by 
 Mr. Hobbs, 121 ; report of the 
 arbitrators, 123, 124; a descrip¬ 
 tion of the lock picked, 125; 
 
 letters from Messrs. Bramah 
 questioning the fairness of the 
 trial, 126; method of picking, 
 110; method employed by Mr. 
 Hobbs, 129; Ainger on the 
 Bramah lock, 110; Farey on the 
 Bramah lock, 113 ; improvements 
 made since 1851, 131. 
 
 Brown’s letter lock, 23; picked by 
 Mr. Hobbs, 139. 
 
 Bullion vaults of the Bank of 
 France, 206. 
 
 Chatwood’s safes described, 203. 
 
 Chinese locks, 171. 
 
 Chubb on Davies’s lock, 112; on 
 lock picking, 132. 
 
 Chubb’s lock, 53 ; described, 54, 
 56; key of, 57 ; attempt to pick, 
 58 ; experiments on, 59; num¬ 
 ber of changes in the lock, 55 ; 
 the detector lock picked by Mr. 
 Hobbs, 115; value of the detec¬ 
 tor questioned, 117 ; improve¬ 
 ments, 121 ; Mr. Hodge on the 
 Chubb lock, 114; Chubb’s new 
 locks, 147 ; hank locks, 149. 
 
 Clockwork, application of, to locks, 
 39. 
 
 Closet-lock, 17. 
 
 Commercial importance of locks, 2. 
 
 Contrivances for adding to the se¬ 
 curity of locks, 35. 
 
 Cut locks, 18. 
 
210 
 
 INDEX. 
 
 Davies’s lock, Captain O’Brien on 
 112; Mr. Chubb on, 112. 
 
 Davis’s lock, 60. 
 
 Day and Newell’s lock, 86 ; Parau- 
 toptic lock, 89 et seq. 
 
 Dead-lock, 17. 
 
 Denison’s large lock, 142; small 
 ditto, 146. 
 
 Dial locks, 23 ; method of picking, 
 138. 
 
 Dukamel du Monceau’s Art du Ser- 
 rurier, 4. 
 
 Iron safes, value of, 201 ; the best 
 position for a safe, 204; cham¬ 
 ber for jewellers’ safes described, 
 205 ; arrangement of bank safes, 
 205 ; Chatwood’s safes, 203. 
 
 Kemp’s union lock, 81. 
 
 Keys, master, 31; skeleton, 30; 
 Mackinnon’s key, 62; Machin’s 
 web key, 154. 
 
 Knob lock, 17. 
 
 Egyptian door-fastenings, 13. 
 
 Egyptian pin-lock, 14; method of 
 picking, 139. 
 
 Escutcheon, uses of the, explained, 
 37. 
 
 Exhibition of 1851, effects of the, 
 in improving English locks, 140 ; 
 Jury Report on locks, 131 ; ob¬ 
 servations on the Report, 133. 
 
 Farey on the Bramah lock, 113. 
 
 Eenby on warded locks, 173; on 
 tumbler locks, 174. , 
 
 Fenby’s adytic lock, 176; machine 
 for making the keys of, 185; 
 number of changes in the, 188; 
 advantages of, 189; discussion 
 on the value of the lock, 192; 
 stop-lock, 196 ; machines for the 
 manufacture of the locks, 200. 
 
 Fons, Mr. de la, his improvement in 
 locks, 148. 
 
 French locks, ancient, 32. 
 
 Friend’s secret lock, 39. 
 
 Greek locks, 9. 
 
 Hobbs on English locks made be¬ 
 fore 1851, 115 ; he picks a 
 
 Chubb lock, 116; a Bramah lock 
 picked by Mr. Hobbs, 122; his 
 mode of picking the Bramah 
 lock described, 129 ; Mr. Brown’s 
 letter-lock picked by him, 139. 
 
 Hobbs’s protector lock, 99. 
 
 Hodge on the Chubb lock, 114. 
 
 Iron-rim lock, 17. 
 
 Lacedaemonian lock, 11. 
 
 Left-hand lock, 17- 
 
 Letter locks, 22 ; method of pick¬ 
 ing, 138. 
 
 Lever locks, 43. 
 
 Literature of lock-making, 4; list of 
 references to the “ Transactions 
 of the Society of Arts ” relating 
 to lock-making, 166. 
 
 Lock classification, 17. 
 
 Lock controversy, 102 ; previous to 
 the Great Exhibition, 103 ; Mr. 
 Chubb on Davies’s lock, 112; 
 Captain O’Brien on Davies’s and 
 other locks, 112; Mr. Farey on 
 the Bramah lock, 113; Mr. 
 Hodge on locks, 114; lock con¬ 
 troversy during and since the 
 Great ^Exhibition, 115 ; Mr. 
 Hobbs on English locks, 115; 
 he picks the Chubb lock, 116; 
 the Bramah lock picked by him, 
 121 ; statements of Messrs. Bra¬ 
 mah, 125 ; attempt of Messrs. 
 Garbutt to pick the parauteptic 
 lock, 134. 
 
 Lock manufacture at Wolverhamp¬ 
 ton, state of, described, 154. 
 
 Lock-picking, distinction between 
 “ picking ” and “ ringing the 
 changes” on a lock, 136; ten¬ 
 tative process of picking, 110; 
 method of picking letter and dial 
 locks, 138; mode of picking the 
 Egyptian lock, 139; method of 
 picking tumbler locks, 118; 
 method of picking the Yale lock, 
 140; Mr. Chubb on lock-pick- 
 
INDEX. 
 
 211 
 
 imc, 182; contrivances to pre¬ 
 vent the picking of locks, lOo. 
 
 Lock trophy, Anbin’s 166; locks 
 composing the, described, 16b. 
 
 Lock and key, improved, 1 1 6. 
 
 Locks, English patents for 164 
 Jury Report, Exhibition of i»hl, 
 on 181; observations on the Re- 
 port 183 ; effects of the Exhi¬ 
 bition of 1851 in improving 
 English locks, 140; use of ma¬ 
 chinery in the manufacture ot, 
 
 163 , 200 . , . „ 
 
 Locks, &c., invented by the Mar¬ 
 quis of Worcester, 35. 
 
 Locks and keys, literature of, 4 ; list 
 of references in the “ Transactions 
 of the Society of Arts ” relating 
 to, 166. 
 
 Louis XVI., his fondness for lock¬ 
 making, 26, 35. 
 
 Machin’s web key, 61. 
 
 Mackinnon’s key, 62. 
 
 Manufacture of locks and keys at 
 
 Wolverhampton, state of the, 154. 
 
 Marshall’s secret escutcheon, 37. 
 Master keys, 31. 
 
 Meighan’s alarum lock, 40. 
 
 Mitchell and Lawton’s tumbler lock, 
 52. 
 
 Mortise locks, 17, 18. 
 
 Multiple-bolt locks, 41. 
 
 Nettlefold’s lock, 60. 
 
 Newell’s parautoptic lock, 89. 
 
 O’Brien, Captain, on Davies’s lock, 
 
 112 . 
 
 Owen’s experiments on Chubb and 
 Bramah locks, 59. 
 
 Parautoptic lock, 89; key, 91; 
 Austrian Report on, 93 ; English 
 patent for, 98; attempts to pick 
 the, in America, 106 ; Report of 
 the American Institute on the lock, 
 107; latest challenge issued by 
 Messrs. Day and Newell, 108; 
 Mr. Garbutt’s attempt to pick 
 
 the, 134 ; failure of the attempt, 
 
 1.35. 
 
 Parnell’s defiance lock, 141. 
 
 Parson’s lock, 61. 
 
 Patents, English, for locks, lb4. 
 Pin-lock of Egypt, 14. 
 
 Puzzle-lock, 19. 
 
 Regnier’s puzzle locks, 21. 
 
 Right-hand lock, 17- 
 Ring lock, 17- 
 Roman locks, 10. 
 
 Rowutree’s tumbler lock, 50. 
 
 Russell’s screw-lock for casks, 38. 
 Russian locks, 171- 
 Rntherford’s lock, 39. 
 
 Ruxton’s detector for tumbler locks, 
 
 53. 
 
 Safes, value of iron, 201 ; Chat- 
 wood’s, 203 ; see also Iron Safes. 
 Saxby’s prize lock, 152 ; picked by 
 Mr. Hobbs, 153. 
 
 Screw locks, 38. 
 
 Skeleton keys, 30. 
 
 Society of Arts’ prize look, 30. 
 Somerford’s lock, 60. 
 
 Spring-stock lock, 17. 
 
 Stansbury’s lock, 83. 
 
 Stop lock, Eenby’s, 196. 
 
 Straight locks, 18. 
 
 Tentative process of lock-picking, 
 
 110 . 
 
 Three bolt lock, 17. 
 
 Tumbler locks, 43 ; lock described 
 by M. de Reaumur, 46 ; modern 
 tumbler lock, 52; introduction of 
 the detector, 53; Chubb’s lock, 
 53, 56; key of, 57; advantages 
 and defects of tumbler locks, 63 ; 
 Hobbs’s method of adjustment, 63. 
 Tumbler locks, Mr. Eenby on, 174 ; 
 method of picking, 118 ; double 
 action, 49. 
 
 Two-bolt lock, 17. 
 
 Ward locks, 18. 
 
 Warded locks, 27 ; action of the 
 key on the wards, 28 ; insecurity 
 of, 29 ; warded locks of the last 
 
212 
 
 INDEX. 
 
 century, 31; insecurity of, illus¬ 
 trated by Mr. Chubb, 34; Bra¬ 
 mah on the defects of, 6G ; Mr. 
 Tenby on, 173. 
 
 Wheel locks, 18. 
 
 Wheel and pinion, application of, to 
 locks, 39. 
 
 Williams’s lock, 62. 
 
 Wolverhampton, account of the 
 
 state of the lock and key manu¬ 
 facture at, 154. 
 
 Worcester, inventions of the Mar¬ 
 quis of, relating to lock-making, 
 35. 
 
 Yale’s lock, 83 ; method of picking, 
 140. 
 
 Yale’s cylinder lock, 152. 
 
 THE END. 
 
 PRINTED BV VIRTUE AND CO., CITY ROAD, LONDON. 
 
WEALE’S SERIES 
 
 OF 
 
 SCIENTIFIC and TECHNICAL 
 
 WORKS. 
 
 “ It is not too much to say that no books have ever proved more 
 popular with or more useful to young engineers and others than the 
 excellent treatises comprised in Weale’s Series.”— Engineer. 
 
 ^ jbUiu Classif kb IlizL 
 
 PAGE 
 
 CIVIL ENGINEERING AND SURVEYING 2 
 MINING AND METALLURGY .... 3 
 
 MECHANICAL ENGINEERING .... 4 
 
 NAVIGATION, SHIPBUILDING. ETC. . 5 
 
 PAGE 
 
 6 
 
 ARCHITECTURE AND BUILDING 
 INDUSTRIAL AND USEFUL ARTS. . 9 
 
 AGRICULTURE, GARDENING, ETC. . 10 
 
 MATHEMATICS, ARITHMETIC, ETC. . 12 
 
 BOOKS OF REFERENCE AND MISCELLANEOUS VOLUMES 
 
 14 
 
 I 
 
 CROSBY LOCKWOOD AND SON, 
 
 7, STATIONERS’ HALL COURT, LONDON, E.C. 
 1897. 
 
2 WEALE’s SCIENTIFIC AND TECHNICAL SERIES. 
 
 CIVIL ENGINEERING & SURVEYING. 
 
 Civil Engineering. 
 
 By Henry Law, M. Inst. C.E. Including a Treatise on Hydraulic 
 Engineering by G. R. Burnell, M.I.C.E. Seventh Edition, revised, 
 with Large Additions by D. K. Clark, M.I.C.E. . . .6/6 
 
 Pioneer Engineering: 
 
 A Treatise on the Engineering Operations connected with the Settlement of 
 Waste Lands in New Countries. By Edward Dobson, A.I.C.E. With 
 numerous Plates. Second Edition. 4/6 
 
 Iron Bridges of Moderate Span: 
 
 Their Construction and Erection. By Hamilton W. Pendred. With 40 
 Illustrations. 2/0 
 
 Iron (Application of) to the Construction of Bridges, 
 Roofs, and other Works. 
 
 By Francis Campin, C.E. Fourth Edition. 2/6 
 
 Constructional Iron and Steel Work, 
 
 as applied to Public, Private, and Domestic Buildings. By Francis 
 Campin, C.E. 3/6 
 
 Tubular and other Iron Girder Bridges. 
 
 Describing the Britannia and Conway Tubular Bridges. By G. Drysdale 
 Dempsey, C.E. Fourth Edition. 2/0 
 
 Materials and Construction: 
 
 A Theoretical and Practical Treatise on the Strains, Designing, and Erec 
 tion of Works of Construction. By Francis Campin, C.E. . 3/0 
 
 Sanitary Work in the Smaller Towns and in Villages. 
 
 By Charles Slagg, Assoc. M. Inst. C.E. Second Edition . . 3/0 
 
 Roads and Streets (The Construction of). 
 
 In Two Parts : I. The Art of Constructing Common Roads, by H. 
 Law, C.E., Revised by D. K. Clark, C.E. ; II. Recent Practice : In¬ 
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 Gas Works (The Construction of), 
 
 And the Manufacture and Distribution of Coal Gas. By S. Hughes, C.E. 
 Re-written by William Richards, C.E. Eighth Edition . . 5/6 
 
 Water Works 
 
 For the Supply of Cities and Towns. With a Description of the Principal 
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 The Drainage of Lands, Towns, and Buildings. 
 
 By G. D. Dempsey, C.E. Revised, with large Additions on Recent 
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 Embanking Lands from the Sea. 
 
 With Particulars of actual Embankments, 8tc. By John Wiggins . 2/0 
 
 The Blasting and Quarrying of Stone, 
 
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 Foundations and Concrete Works. 
 
 With Practical Remarks on Footings, Planking, Sand, Concrete, B£ton, 
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WEALE*S SCIENTIFIC AND TECHNICAL SERIES. 3 
 
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 Land and Engineering Surveying. 
 
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 MINING AND METALLURGY. 
 
 Mineralogy, 
 
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 enlarged. Woodcuts and Plates. 3/6 
 
 Coal and Coal Mining, 
 
 A Rudimentary Treatise on. By the late Sir Warington W. Smyth, 
 F.R.S. Seventh Edition, revised and enlarged . . . . *3/6 
 
 Metallurgy of Iron. 
 
 Containing Methods of Assay, Analyses of Iron Ores, Processes of Manu¬ 
 facture of Iron and Steel, &c. By H. Bauekman, F.G.S. With numerous 
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 The Mineral Surveyor and Valuer’s Complete Guide. 
 
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 Angular Surveying. 3/S 
 
 Slate and Slate Quarrying: 
 
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 numerous Illustrations and Folding Plates. Third Edition . . 3/0 
 
 A First Book of Mining and Quarrying, 
 
 with the Sciences connected therewith, for Primary Schools and Self In¬ 
 struction. By J. H. Collins, F.G.S. Second Edition . . .1/6 
 
 Subterraneous Surveying, 
 
 with and without the Magnetic Needle. By T. Fenwick and T. Baker, 
 C.E. Illustrated ..2/6 
 
 Mining Tools. 
 
 Manual of. By William Morgans, Lecturer on Practical Mining at the 
 Bristol School of Mines. 2/6 
 
 Mining Tools, Atlas 
 
 of Engravings to Illustrate the above, containing 235 Illustrations of Mining 
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 E lectro-Metallurgy, 
 
 Practically Treated. By Alexander Watt. Ninth Edition, enlarged 
 and revised, including the most Recent Processes .... 3/6 
 
4 Weale’s scientific and technical series. 
 
 MECHANICAL ENGINEERING. 
 
 The Workman’s Manual of Engineering Drawing. 
 
 By John Maxton, Instructor in. Engineering Drawing, Royal Naval 
 College, Greenwich. Seventh Edition. 300 Plates and Diagrams . 3/6 
 
 Fuels: Solid, Liquid, and Gaseous. 
 
 Their Analysis and Valuation. For the Use of Chemists and Engineers. 
 By H. J. Phillips, F.C.S., formerly Analytical and Consulting Chemist 
 to the Great Eastern Railway. Second Edition, Revised. . *2/0 
 
 Fuel, Its Combustion and Economy. 
 
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 The Boilermaker’s Assistant 
 
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 1/6 
 
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 Mechanical Engineering. 
 
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weale’s scientific and technical series. 5 
 
 Elementary Engineering: 
 
 A Manual for Young Marine Engineers and Apprentices. In the Form of 
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 By J. S. Brewer. Second Edition.2/0 
 
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 Iron and Heat, 
 
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 Pillars, and Girders. By J. Armour, C.E..2/6 
 
 Practical Mechanism, 
 
 And Machine Tools. By T. Baker, C.E. With Remarks on Tools and 
 Machinery, by J. Nasmyth, C.E. -2/6 
 
 Mechanics: 
 
 Being a concise Exposition of the General Principles of Mechanical Science, 
 and their Applications. By Charles Tomlinson, F.R.S. . .1/6 
 
 Cranes (The Construction of), 
 
 And other Machinery for Raising Heavy Bodies for the Erection of Build¬ 
 ings, &c. By Joseph Glynn, F.R.S.1/6 
 
 NAVIGATION, SHIPBUILDING, ETC. 
 
 The Sailor’s Sea Book: 
 
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 With numerous Woodcuts and Coloured Plates. New and enlarged 
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 Rosser ; together with Mathematical and Nautical Tables for the Working 
 of the Problems, by Henry Law, C.E., and Prof. J. R. Young . 7/0 
 
 Navigation and Nautical Astronomy, 
 
 In Theory and Practice. By Prof. J. R. Young. New Edition. 2/6 
 
 Mathematical Tables, 
 
 For Trigonometrical, Astronomical, and Nautical Calculations ; to which is 
 prefixed a Treatise on Logarithms. By H. Law, C.E. Together with a 
 Series of Tables for Navigation and Nautical Astronomy. By Professor J. 
 
 R. Young. New Edition.4/0 
 
 Masting, Mast-Making, and Rigging of Ships. 
 
 Also Tables of Spars, Rigging, Blocks; Chain, Wire, and Hemp Ropes, 
 &c., relative to every class of vessels. By Robert Kipping, N.A. . 2/0 
 
 Sails and Sail-Making. 
 
 With Draughting, and the Centre of Effort of the Sails. By Robert 
 Kipping, N.A.2/6 
 
 Marine Engines and Steam Vessels. 
 
 By R. Murray, C.E. Eighth Edition, thoroughly Revised, with Addi¬ 
 tions by the Author and by George Carlisle, C.E. . . . 4/6 
 
 Iron Ship-Building. 
 
 With Practical Examples. By John Grantham. Fifth Edition . 4/0 
 
 Naval Architecture : 
 
 An Exposition of Elementary Principles. By James Peake . . 3/6 
 
 Ships for Ocean and River Service, 
 
 Principles of the Construction of. By Hakon A. Sommerfeldt . 1 /Q 
 
 Atlas of Engravings 
 
 To Illustrate the above. Twelve large folding Plates. Royal 4 to, cloth 7/6 
 
 The Forms of Ships and Boats. 
 
 By W. Bland. Seventh Edition, revised, with numerous Illustrations and 
 Models 1 /g 
 
6 weale’s scientific and technical series. 
 
 ARCHITECTURE AND THE 
 
 BUILDING ARTS. 
 
 Constructional Iron and Steel Work, 
 
 as applied to Public, Private, and Domestic Buildings. By Francis 
 Campin, C.E. 3/6 
 
 Building Estates: 
 
 A Treatise on the Development, Sale, Purchase, and Management of Build¬ 
 ing Land. By F. Maitland. Second Edition, revised . . 2/0 
 
 The Science of Building : 
 
 An Elementary Treatise on the Principles of Construction. By E. Wynd- 
 ham Tarn, M.A. Lond. Third Edition, revised and enlarged . 3/6 
 
 The Art of Building: 
 
 General Principles of Construction, Strength, and Use of Materials, Working 
 Drawings, Specifications, &c. By Edward Dobson, M.R.I.B.A. . 2/0 
 
 A Book on Building, 
 
 Civil and Ecclesiastical. By Sir Edmund Beckett, Q.C. (Lord Grim- 
 thorpe). Second Edition. 4/6 
 
 Dwelling-Houses (The Erection of), 
 
 Illustrated by a Perspective View, Plans, and Sections of a Pair of Villas, with 
 Specification, Quantities, and Estimates. By S. H. Brooks, Architect 2/6 
 
 Cottage Building. 
 
 By C. Bruce Allen. Eleventh Edition, with Chapter on Economic Cot¬ 
 tages for Allotments, by E. E. Allen, C.E. 2/0 
 
 Acoustics in Relation to Architecture and Building: 
 
 The Laws of Sound as applied to the Arrangement of Buildings. By Pro¬ 
 fessor T. Roger Smith, F.R.I.B.A. New Edition, Revised . . 1/6 
 
 The Rudiments of Practical Bricklaying. 
 
 General Principles of Bricklaying ; Arch Drawing, Cutting, and Setting; 
 Pointing ; Paving, Tiling, &c. By Adam Hammond. With 68 Woodcuts 
 
 1/6 
 
 The Art of Practical Brick Cutting and Setting. 
 
 By Adam Hammond. With 90 Engravings. 1/6 
 
 Brickwork: 
 
 A Practical Treatise, embodying the General and Higher Principles of 
 Bricklaying, Cutting and Setting; with the Application of Geometry to Roof 
 Tiling, &c. By F. Walker.1/6 
 
 Bricks and Tiles, 
 
 Rudimentary Treatise on the Manufacture of; containing an Outline of the 
 Principles of Brickmaking. By E. Dobson, M.R.I.B.A. Additions by 
 C. Tomlinson, F.R.S. Illustrated. 3/0 
 
 The Practical Brick and Tile Book. 
 
 Comprising: Brick and Tile Making, by E. Dobson, A.I.C.E. ; Prac¬ 
 tical Bricklaying, by A. Hammond ; Brickwork, by F. Walker. 
 550 pp. with 270 Illustrations, strongly half-bound .... 6/0 
 
 Carpentry and Joinery— 
 
 The Elementary Principles of Carpentry. Chiefly composed from the 
 Standard WorkofTHOMAS Tredgold,C.E With Additions, and Treatise 
 on Joinery, by E. W. Tarn, M.A. Fifth Edition, Revised . . 3/6 
 
 Carpentry and Joinery—Atlas 
 
 Of 35 Plates to accompany and illustrate the foregoing book. With 
 Descriptive Letterpress. 4 to. . , . . . , . .6/0 
 
WEALE’S SCIENTIFIC AND TECHNICAL SERIES. 7 
 
 A Practical Treatise on Handrailing; 
 
 Showing New and Simple Methods. By Geo. Colungs. Second Edition. 
 Revised, including a Treatise on Stairbuilding. With Plates . 2/6 
 
 Circular Work in Carpentry and Joinery. 
 
 A Practical Treatise on Circular Work of Single and Double Curvature. 
 By George Collings. Second Edition. 2/6 
 
 Roof Carpentry: 
 
 Practical Lessons in the Framing of Wood Roots. For the Use of Working 
 Carpenters. By Geo. Collings. 2/0 
 
 The Construction of Roofs of Wood and Iron; 
 
 Deduced chiefly from the Works of Robison, Tredgold, and Humber. By 
 E. Wyndham Tarn, M.A., Architect. Second Edition, revised . 1/6 
 
 The Joints Made and Used by Builders. 
 
 By Wyvill J. Christy, Architect. With 160 Woodcuts . . 3/0 
 
 Shoring 
 
 And Its Application : A Handbook for the Use of Students. By George 
 H. Blagrove. With 31 Illustrations. 1/6 
 
 The Timber Importer’s, Timber Merchant’s, and 
 Builder’s Standard Guide. 
 
 By R. E. Grandy. 2/0 
 
 Plumbing: 
 
 A Text-Book to the Practice of the Art or Craft of the Plumber. With 
 Chapters upon House Drainage and Ventilation. By Wm. Paton Buchan. 
 Sixth Edition, revised and enlarged, with 380 Illustrations . . 3/6 
 
 Ventilation: 
 
 A Text Book to the Practice of the Art of Ventilating Buildings. By W. P. 
 Buchan, R.P., Author of “ Plumbing,” &c. With 170 Illustrations 3/6 
 
 The Practical Plasterer: 
 
 A Compendium of Plain and Ornamental Plaster Work. By W. Kemp 2/0 
 
 House Painting, Graining, Marbling, & Sign Writing. 
 
 With a Course of Elementary Drawing, and a Collection of Useful Receipts. 
 By Ellis A. Davidson. Sixth Edition. Coloured Plates . . 5/0 
 
 *** The above , in cloth boards , strongly bound , 6 s . 
 
 A Grammar of Colouring, 
 
 Applied to Decorative Painting and the Arts. By George Field. New 
 Edition, enlarged, by Ellis A. Davidson. With Coloured Plates . 3/0 
 
 Elementary Decoration 
 
 As applied to Dwelling Houses, &c. By James W. Facey. Illustrated 2/0 
 
 Practical House Decoration. 
 
 A Guide to the Art of Ornamental Painting, the Arrangement of Colours in 
 Apartments, and the Principles of Decorative Design. By James W. Facey. 
 
 2/6 
 
 *** The last two Works in One handsome Vol ., half - bound , entitled “House 
 Decoration, Elementary and Practical,” price 5$. 
 
 Warming and Ventilation 
 
 Of Domestic and Public Buildings, Mines, Lighthouses, Ships, &c. By 
 Charles Tomlinson, F.R.S. 3/0 
 
 Portland Cement for Users. 
 
 By Henry Faija, A.M. Inst. C.E. Third Edition, Corrected . 2/0 
 
 Limes, Cements, Mortars, Concretes, Mastics, Plas¬ 
 tering, &c. 
 
 By G. R. Burnell, C.E, Thirteenth Edition 
 
 . 1/6 
 
8 weale’s scientific and technical series. 
 
 Masonry and Stone-Cutting. 
 
 The Principles of Masonic Proiection and their application to Construction. 
 By Edward Dobson, M.R.I.B.A.2/6 
 
 Arches, Piers, Buttresses, &c.: 
 
 Experimental Essays on the Principles of Construction . By W. Bland. 
 
 1/6 
 
 Quantities and Measurements, 
 
 In Bricklayers’, Masons’, Plasterers’; Plumbers', Painters’, Paperhangers’, 
 Gilders', Smiths’, Carpenters’ and Joiners’Work. By A. C. Beaton 1 /6 
 
 The Complete Measurer: 
 
 Setting forth the Measurement of Boards, Glass, Timber and Stone. By R. 
 
 Horton. Fifth Edition .4-/0 
 
 *** The above , strongly bound in leather, price 5 $. 
 
 Light: 
 
 An Introduction to the Science of Optics. Designed for the Use of Students 
 of Architecture, Engineering, and other Applied Sciences. By E. Wynd- 
 ham Tarn, M. A., Author of “ The Science of Building,” &c. . .1/6 
 
 Hints to Young Architects. 
 
 By George Wightwick, Architect. Fifth Edition, revised and enlarged 
 by G. Huskisson Guillaume, Architect.3/6 
 
 Architecture—Orders: 
 
 The Orders and their ./Esthetic Principles. By W. H. Leeds. Illustrated. 
 
 1/6 
 
 Architecture—Styles: 
 
 The History and Description of the Styles of Architecture of Various 
 Countries, from the Earliest to the Present Period. By T. Talbot Bury, 
 
 F.R.I.B.A. Illustrated.2/0 
 
 *** Orders and Styles of Architecture, in Cne Vol ., 3$. 6d. 
 
 Architecture—Design: 
 
 The Principles of Design in Architecture, as deducible from Nature and 
 exemplified in the Works of the Greek and Gothic Architects. By Edw. 
 
 Lacy Garbett, Architect. Illustrated.2/6 
 
 *** The three preceding Works in One handsome Vol., half bound, entitled 
 “Modern Architecture,”/?^* 6s. 
 
 Perspective for Beginners. 
 
 Adapted to Young Students and Amateurs in Architecture, Painting, &c. 
 By George Pyne .2/0 
 
 Architectural Modelling in Paper. 
 
 By T. A. Richardson. With Illustrations, engraved by O. Jewitt 1 /Q 
 
 Class Staining, and the Art of Painting on Glass. 
 
 From the German of Dr. Gessert and Emanuel Otto Fromeerg. With 
 an Appendix on The Art of Enamelling .2/6 
 
 Yitruvius—The Architecture of. 
 
 In Ten Books. Translated from the Latin by Joseph Gwilt, F.S.A., 
 
 F.R.A.S. With 23 Plates.5/0 
 
 N.B. — This is the only Edition ^/Vitruvius procurable at a moderate price. 
 
 Grecian Architecture, 
 
 An Inquiry into the Principles of Beauty in. With an Historical View of the 
 Rise and Progress of the Art in Greece. By the Earl of Aberdeen 1 /Q 
 *** The two preceding Works in One handsome Vol., half bound, entitled 
 “Ancient Architecture,”/??V* 6s. 
 
WEALES SCIENTIFIC AND TECHNICAL SERIES. 9 
 
 INDUSTRIAL AND USEFUL ARTS. 
 
 Cements, Pastes, Glues, and Gums. 
 
 A Practical Guide to the Manufacture and Application of the various 
 Agglutinants required for Workshop, Laboratory, or Office Use. With 
 upwards of 900 Recipes and Formulae. By H. C. Standage . . 2/0 
 
 Clocks and Watches, and Bells, 
 
 A Rudimentary Treatise on. By Sir Edmund Beckett, Q.C. (Lord 
 Grimthorpe). Seventh Edition.4/6 
 
 Goldsmith's Handbook. 
 
 Containing full Instructions in the Art of Alloying, Melting, Reducing, 
 Colouring, Collecting and Refining, Recovery of Waste, Solders, Enamels, 
 &c., &c. By George E. Gee. Third Edition, enlarged . . . 3/0 
 
 Silversmith’s Handbook, 
 
 On the same plan as the Goldsmith’s Handbook. By George E. Gee. 
 Second Edition, Revised . . . . . . . . *3/0 
 
 *** The last two Works , in One handsome Vol. } half-bound, js. 
 
 Hall-Marking of Jewellery. 
 
 Comprising an account of all the different Assay Towns of the United 
 Kingdom; with the Stamps and Laws relating to the Standards and Hall- 
 Marks at the various Assay Offices. By George E. Gee . . 3/0 
 
 Practical Organ Building. 
 
 By W. E. Dickson, M.A. Second Edition,Revised, with Additions 2/6 
 
 Coach-Building: 
 
 A Practical Treatise. By James W. Burgess. With 57 Illustrations 2/6 
 
 The Brass Founder’s Manual: 
 
 Instructions for Modelling, Pattern Making, Moulding. Turning, &c. By 
 
 W. Graham.. . . . . 2/0 
 
 The Sheet-Metal Worker’s Guide. 
 
 A Practical Handbook for Tinsmiths, Coppersmiths, Zincworkers, &c., with 
 46 Diagrams. By W. J. E. Crane. Second Edition, revised . 1 /6 
 
 Sewing Machinery: 
 
 Its Construction, History, &c. With full Technical Directions for Adjust¬ 
 ing, &c. By J. W. Urquhart, C.E..2/0 
 
 Gas Fitting : 
 
 A Practical Handbook. By John Black. Second Edition, Enlarged. 
 With 130 Illustrations . . . . . . . . . -2/6 
 
 Construction of Door Locks. 
 
 From the Papers of A. C. Hobbs. Edited by Charles Tomlinson, F.R.S. 
 With a Note upon Iron Safes by Robert Mallet. Illustrated . 2/6 
 
 The Model Locomotive Engineer, Fireman, and 
 Engine-Boy. 
 
 Comprising an Historical Notice of the Pioneer Locomotive Engines and 
 their Inventors. By Michael Reynolds. Second Edition. With 
 numerous Illustrations, and Portrait of George Stephenson . . 3/6 
 
 The Art of Letter Painting made Easy. 
 
 By J. G. Bauenoch. With 12 full-page Engravings of Examples . 1 JQ 
 
 The Art of Boot and Shoemaking. 
 
 Including Measurement, Last-fitting, Cutting-out, Closing and Miking. By 
 John Bedford Leno. With numerous Illustrations. Third Edition 2/0 
 
 Mechanical Dentistry: 
 
 A Practical Treatise on the Construction of the Various Kinds of Artificial 
 Dentures. By Charles Hunter. Third Edition, revised . . 3/0 
 
 Wood Engraving: 
 
 A Practical and Easy Introduction to the Art. By W. N. Brown . 1 /Q 
 
 Laundry Management. 
 
 A Handbook for Use in Private and Public Laundries. Including Accounts 
 of Modern Machinery and Appliances. By the Editor of “ The Laundry 
 Journal.” With numerous Illustrations. Second Edition . . 2/0 
 
 The 
 
 The 
 
 The 
 
10 weale’s scientific and technical series. 
 
 AGRICULTURE, GARDENING, ETC. 
 
 Draining and Embanking: 
 
 A Practical Treatise. By Prof. John Scott. With 68 Illustrations 1/6 
 
 Irrigation and Water Supply: 
 
 A Practical Treatise on Water Meadows, Sewage Irrigation, Warping, &c.; 
 on the Construction of Wells, Ponds, Reservoirs, &c. By Prof. John 
 Scott. With 34 Illustrations. 1/6 
 
 Farm Roads, Fences, and Gates: 
 
 A Practical Treatise on the Roads, Tramways, and Waterways of the 
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 CROSBY LOCKWOOD & SON'S 
 (Eatal00tu af 
 
 Scientific, Technical and 
 Industrial Books. 
 
 PAGE 
 
 MECHANICAL ENGINEERING . 1 
 CIVIL ENGINEERING .... 9 
 MARINE ENGINEERING, &c. . 17 
 
 MINING & METALLURGY • . . 19 
 
 ELECTRICITY.23 
 
 ARCHITECTURE & BUILDING . 25 
 CARPENTRY & TIMBER ... 28 
 
 LAW & MISCELLANEOUS 
 
 PAGE 
 
 DECORATIVE ARTS.30 
 
 NATURAL SCIENCE.32 
 
 CHEMICAL MANUFACTURES . 34 
 
 INDUSTRIAL ARTS.36 
 
 COMMERCE, TABLES, &c. . . 41 
 
 AGRICULTURE & GARDENING- 43 
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 .47 
 
 MECHANICAL ENGINEERING, &c. 
 
 THE MECHANICAL ENGINEER’S POCKET=BOOK. 
 
 Comprising Tables, Formulae, Rules, and Data : A Handy Book of Reference 
 for Daily Use in Engineering Practice. By D. Kinnear Clark, M. Inst. C.E., 
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 rounded corners. 6/0 
 
 Summary of Contents:—Mathematical Tables.—Measurement of Sur¬ 
 faces and Solids.—English and Foreign Weights and Measures—Moneys— 
 Specific Gravity, Weight, and Volume.—Manufactured Metals.—Steel Pipes. 
 — Bolts and Nuts.— Sundry Articles in Wrought and Cast Iron, Copper, 
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 Transmission of motive Power—Heat—Combustion : Fuels—Warming, Venti¬ 
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 “ Mr. Clark manifests what is an innate perception of what is likely to be useful in a pocket- 
 book, and he is really unrivalled in the art of condensation. It is very difficult to hit upon any 
 mechanical engineering subject concerning which this work supplies no information, and the 
 excellent index at the end adds to its utility. In one word, it is an exceedingly handy and efficient 
 tool, possessed of which the engineer will be saved many a wearisome calculation, or yet more 
 wearisome hunt through various text-books and treatises, and, as such, we can heartily recommend 
 it to our readers ."—The Engineer. 
 
 “ It would be found difficult to compress more matter within a similar compass, or produce a 
 book of 650 pages which should be more compact or convenient for pocket reference. . . , Will 
 be appreciated by mechanical engineers of all classes .”—Pi actical Engineer. 
 
CROSBY LOCKWOOD & SON'S CATALOGUE. 
 
 MR. HUTTON’S PRACTICAL HANDBOOKS. 
 
 THE WORKS’ MANAGER’S HANDBOOK. 
 
 Comprising Modern Rules. Tables, and Data. For Engineers, Millwrights, 
 and Boiler Makers ; Tool Makers, Machinists, and Metal Workers ; Iron and 
 Brass Founders, 8 zc. By W. S. Hutton, Civil and Mechanical Engineer, 
 Author of “The Practical Engineer’s Handbook.” Fifth Edition, carefully 
 Revised, with Additions. In One handsome Volume, medium 8vo, strongly 
 bound. 1 5/0 
 
 The Author having'compiled Rules and Data for his own use in a great 
 variety of modern engineering work , and having found his notes extremely useful , 
 decided to publish them—revised to date—believing that a practical work . suited to 
 the daily requirements of modern engineers, would be favour ably received. 
 
 "Of this edition we may repeat the appreciative remarks we made upon the first and third. 
 Since the appearance of the latter very considerable modifications have been made, although the 
 total number of pages remains almost the same. It is a very useful collection of rules, tables, and 
 workshop and drawing office data."— The Engineer . May io, 1895. 
 
 “ The author treats every subject from the point of view of one who has collected workshop 
 notes for application in workshop practice, rather than from the theoretical or literary aspect. The 
 volume contains a great deal of that kind of information which is gained only by practical experience, 
 and is seldom written in books." —The Engineer, June 5, 1885. 
 
 “ The volume is an exceedingly useful one, brimful with engineer’s notes, memoranda, and 
 rules, and well worthy of being on every mechanical engineer's bookshelf."— Mechanical World. 
 
 " The information is precisely that likely to be required in practice. . . . The work forms 
 a desirable addition to the library not only of the works' manager, but of any one connected with 
 general engineering.”— Mining Journal. 
 
 "Brimful of useful information, stated in a concise form, Mr. Hutton's books have met a 
 pressing want among engineers. The book must prove extremely useful to every practical man 
 possessing a copy.”— Practical Engineer. 
 
 THE PRACTICAL ENGINEER’S HANDBOOK. 
 
 Comprising a Treatise on Modern Engines and Boilers, Marine, Locomotive, 
 and Stationary. And containing a large collection of Rules and Practical 
 Data relating to Recent Practice in Designing and Constructing all kinds of 
 Engines, Boilers, and other Engineering work. The whole constituting a com¬ 
 prehensive Key to the Board of Trade and other Examinations for Certificates 
 of Competency in Modern Mechanical Engineering. By Walter S. Hutton, 
 Civil and Mechanical Engineer, Author of “The Works’ Manager’s Handbook 
 for Engineers,” &c. With upwards of 370 Illustrations. Fifth Edition, 
 Revised with Additions. Medium 8 vo, nearly 500 pp., strongly bound. 
 
 [Just Published. 1 8 0 
 
 This Work is designed as a companion to the Author's “Works’ 
 Manager’s Handbook.” It possesses many new and original features , and con¬ 
 tains , like its predecessor , a quantity of matter not originally intended for publication , 
 but collected by the Author for his own use in the construction of a great variety of 
 Modern Engineering Work. 
 
 The information is given in a condensed and concise form , and is illustrated by 
 upwards of 370 Woodcuts; and comprises a quantity of tabulated matter of great 
 value to all engaged in designing , constructing, or estimating for Engines, Boilers, 
 and other Engineering Work. 
 
 "We have kept it at hand for several weeks, referring to it as occasion arose, and we have not 
 on a single occasion consulted its pages without finding the information of which we were in quest." 
 ■— Athenaum. 
 
 " A thoroughly good practical handbook, which no engineer can go through without learning 
 something that will be of service to him." —Marine Engineer. 
 
 " An excellent book of reference for engineers, and a valuable text-book for students of 
 engineering."— Scotsman. 
 
 "This valuable manual embodies the results and experience of the leading authorities on 
 mechanical engineering." —Building News. 
 
 “ The author has collected together a surprising quantity of rules and practical data, and has 
 shown much judgment in the selections he has made. . . . There is no doubt that this book is 
 one of the most useful of its kind published, and will be a very popular compendium."— Engineer. 
 
 “ A mass of information set down in simple language, and in such a form that it can be easily 
 referred to at any time. The matter is uniformly good and well chosen, and is greatly elucidated 
 by the illustrations. The book will find its way on to most engineers' shelves, where it will rank as 
 one of the most useful books of reference.”— Practical Engineer. 
 
 " Full of useful information, and should be found on the office shelf of all practical engineers. 
 —English Mechanic. 
 
MECHANICAL ENGINEERING, &-c. 
 
 3 
 
 MR. HUTTON’S PRACTICAL HANDBOOKS — continued. 
 
 STEAM BOILER CONSTRUCTION. 
 
 A Practical Handbook for Engineers, Boiler-Makers, and Steam Users. 
 Containing a large Collection of Rules and Data relating to Recent Practice 
 in the Design, Construction, and Working of all Kinds of Stationary, Loco¬ 
 motive, and Marine Steam-Boilers. By Walter S. Hutton, Civil and 
 Mechanical Engineer, Author of “ The Works’ Manager’s Handbook,” “The 
 Practical Engineer's Handbook,” &c. With upwards of 300 Illustrations. 
 Second Edition, medium 8vo, cloth ....... 1 8/0 
 
 gjljp This Work is issued in continuation of the Series of Handbooks written 
 by the Author , viz .: —“The Works Manager’s Handbook ” and “ The Practical 
 Engineer’s Handbook,” which are so highly appreciated by engineers for the 
 practical nature of their information ; and is consequently written in the same style 
 as those works . 
 
 The Author believes that the concentration , in a convenient form for easy 
 reference , of such a large amount of thoroughly practical information on Steam - 
 Boilers , will be of considerable service to those for whom it is intended , and he trusts 
 the book may be deemed worthy of as favourable a reception as has been accorded to 
 its predecessors . 
 
 “ Every detail, both in boiler design and management, is clearly laid before the reader. The 
 volume shows that boiler construction has been reduced to the condition of one of the most exact 
 sciences ; and such a book is of the utmost value to the Jin de si'ecle Engineer and Works Manager.” 
 — Marine Engineer. 
 
 “ There has long been room for a modern handbook on steam boilers ; there is not that room 
 now, because Mr. Hutton has filled it. It is a thoroughly practical book for those who are occupied 
 in the construction, design, selection, or use of boilers. ’— Engineer. 
 
 “ The book is of so important and comprehensive a character that it must find its way into the 
 libraries of every one interested in boiler using or boiler manufacture if they wish to be thoroughly 
 informed. We strongly recommend the book for the intrinsic value of its contents.”— Machinery 
 I.Iarket. 
 
 “The value of this book can hardly be over-estimated. The author’s rules, formulce, &c., 
 are all very fresh, and it is impossible to turn to the work and not find what you want. No practical 
 engineer should be without it."— Colliery Guardian. 
 
 PRACTICAL MECHANICS’ WORKSHOP COMPANION. 
 
 Comprising a great variety of the most useful Rules and Formulce in Mechanical 
 Science, with numerous Tables of Practical Data and Calculated Results for 
 Facilitating Mechanical Operations. By William Templeton, Author of 
 “ The Engineer’s Practical Assistant,” &c., &c. Seventeenth Edition, Revised, 
 /Modernised, and considerably Enlarged by Walter S. Hutton, C.E., Author 
 of “The Works’ Manager's Handbook,” “The Practical Engineer’s Hand¬ 
 book,” &c. Fcap. 8vo, nearly 500 pp., with 8 Plates and upwards of 250 Illus¬ 
 trative Diagrams, strongly bound for workshop or pocket wear and tear. 6/0 
 
 “ In its modernised form Hutton's * Templeton ’ should have a wide sale, for it contains much 
 valuabie information which the mechanic will often find of use, and not a few tables and notes which 
 he might look for in vain in other works. This modernised edition will be appreciated by all who 
 have learned to value the original editions of ‘ Templeton.’”— English Mechanic. 
 
 “ It has met with great success in the engineering workshop, as we can testify; and there are 
 a great many men who, in a great measure, owe their rise in life to this little book ."—Building 
 JVews. 
 
 “This familiar text-book—well known to all mechanics and engineers—is of essential service 
 to the every-day requirements of engineers, millwrights, and the various trades connected with 
 engineering and building. The new modernised edition is worth its weight in gold."— Building 
 News. (Second Notice.) 
 
 " This well-known and largely-used book contains information, brought up to date, of the 
 sort so useful to the foreman and draughtsman. So much fresh information has been introduced as 
 to constitute it practically a new book. It will be largely used in the office and workshop.”— 
 Mechanical World. 
 
 “The publishers wisely entrusted the task of revision of this popular, valuable, and useful 
 book to Mr. Hutton, than whom a more competent man they could not have found.”— Iron. 
 
 ENGINEER’S AND MILLWRIGHT’S ASSISTANT. 
 
 A Collection of Useful Tables, Rules, and Data. By William Templeton. 
 Seventh Edition, with Additions. i8mo, cloth. 2/6 
 
 “ Occupies a foremost place among books of this kind. A more suitable present to an 
 apprentice to any of the mechanical trades could not possibly be made .”—Building News. 
 
 “A deservedly popular work. It should be in the ‘drawer’ of every mechanic .”—English 
 Mechanic. 
 
4 
 
 CROSBY LOCKWOOD &> SON'S CATALOGUE. 
 
 THE MECHANICAL ENGINEER’S REFERENCE BOOK. 
 
 For Machine and Boiler Construction. In Two Parts. Part I. General. 
 Engineering Data. Part II. Boiler Construction. With 51 Plates and 
 numerous Illustrations. By Nelson Foley, M.I.N.A. Second Edition, 
 Revised throughout and much Enlarged. Folio, half-bound, net . £3 3s 
 
 Summary of Contents, 
 
 part I. 
 
 Measures.—Circumferences and Areas, &c., Squares, Cubes, Fourth 
 
 POWERS.—SQUARE AND CUBE ROOTS.—SURFACE OF TUBES.—RECIPROCALS.—LOGA¬ 
 RITHMS.—MENSURATION.—SPECIFIC Gravities and weights.—work and power.— 
 Heat.—Combustion. —Expansion and Contraction.—Expansion of Gases.— 
 Steam.—Static Forces.—Gravitation and Attraction.—Motion and Computa¬ 
 tion of Resulting Forces.—Accumulated Work.—Centre and Radius of 
 Gyration.—Moment of Inertia.—Centre of Oscillation.—Electricity.— 
 Strength of Materials.—Elasticity.—Test Sheets of Metals.—Friction.— 
 Transmission of Power.—Flow of Liquids.—Flow of Gases.—Air pumps, Surface 
 Condensers, &c.—Speed of Steamships.—Propellers.—Cutting Tools.—Flanges. 
 —Copper Sheets and Tubes.—Screws, Nuts, Bolt heads, &c.—Various Recipes 
 and Miscellaneous Matter.—With DIAGRAMS for Valve-Gear, Belting and 
 Ropes, Discharge and Suction Pipes, Screw Propellers, and Copper Pipes. 
 
 PART II. 
 
 Treating of Power of Boilers.—Useful Ratios.—Notes on Construction.— 
 Cylindrical Boiler Shells.—Circular Furnaces.—Flat Plates.—Stays.— 
 Girders.—Screws.—Hydraulic Tests.—Riveting.—Boiler Setting, Chimneys, 
 and Mountings.—Fuels, &c.—Examples of Boilers and Speeds of Steamships.— 
 Nominal and Normal Horse Power.—with DIAGRAMS for all Boiler Calcula¬ 
 tions and Drawings of many Varieties of Boilers. 
 
 “The book is one which every mechanical engineer may, with advantage to himself, add to 
 his library.”— Industries. 
 
 “ Mr. Foley is well fitted to compile such a work. . . . The diagrams are a great feature 
 of the work. . . . Regarding the whole work, it maybe very fairly stated that Mr. Foley has 
 produced a volume which will undoubtedly fulfil the desire of the author and become indispensable 
 to all mechanical engineers.”— Marine Engineer. 
 
 “We have carefully examined this work, and pronounce it a most excellent reference book 
 for the use of marine engineers.”— Journal of American Society of Naval Engineers. 
 
 “ A veritable monument of industry on the part of Mr. Foley, who has succeeded in produc¬ 
 ing what is simply invaluable to the engineering profession.”— Steamship. 
 
 coal and speed tables. 
 
 A Pocket Book for Engineers and Steam Users. By Nelson Foley, Author 
 of “ The Mechanical Engineer’s Reference Book.” Pocket-size, cloth . 3 6 
 
 “ These tables are designed to meet the requirements of every-day use; they are of sufficient 
 scope for most practical purposes, and may be commended to engineers and users of steam.”— 
 Iron. 
 
 “ This pocket-book well merits the attention of the practical engineer. Mr. Foley has com¬ 
 piled a very useful set of tables, the information contained in which is frequently required by 
 engineers, coal consumers, and users of steam."— Iron a?id Coal Trades Review. 
 
 TEXT=BOOK ON THE STEAM ENGINE. 
 
 With a Supplement on Gas Engines, and Part II. on Heat Engines. By 
 T. M. Goodeve, M.A., Barrister-at-Law, Professor of Mechanics at the Ro} r al 
 College of Science, London ; Author of “ The Principles of Mechanics,” “ The 
 Elements of Mechanism,” &c. Fourteenth Edition. Crown 8vo, cloth . 6 0 
 
 “ Professor Goodeve has given 11s a treatise on the steam engine which will bear comparison 
 with anything written by Huxley or Maxwell, and we can award it no higher praise. "—Engineer. 
 
 “ Mr. Goodeve's text-book is a work of which every young engineer should possess himself.” 
 —Mining Journal. 
 
 ON GAS ENGINES. 
 
 With Appendix describing a Recent Engine with Tube Igniter. By T. M. 
 
 Goodeve, M.A. Crown 8vo, cloth. 2/6 
 
 “ Like all Mr. Goodeve’s writings, the present is no exception in point of general excellence. 
 It is a valuable little volume."— Mechanical IVorld. 
 
 A treatise on steam boilers. 
 
 Their Strength, Construction, and Economical Working. By R. Wilson, C.E. 
 
 Fifth Edition. i 2 mo, cloth.6 0 
 
 “ The best treatise that has ever been published on steam boilers. — Engineer. 
 
 “The author shows himself perfect master of his subject, and we heartily recommend all 
 employing steam power to possess themselves of the work ."—RylancTs Iron Trade Circular. 
 
MECHANICAL ENGINEERING, &c. 
 
 5 
 
 A HANDBOOK ON THE STEAM ENGINE. 
 
 With especial Reference to Small and Medium-sized Engines. For the Use of 
 Engine Makers, Mechanical Draughtsmen, Engineering Students, and users 
 of Steam Power. By Herman Haeder, C.E. Translated from the German 
 with considerable additions and alterations, by H. H. P. Powles, A.M.I.C.E., 
 M.I.M.E. Second Edition, Revised. With nearly 1,100 Illustrations. 
 Crown 8vo, cloth. 9 0 
 
 “A perfect encyclopedia of the steam engine and its details, and one which must take a per¬ 
 manent place in English drawing-offices and workshops.”— A Foreman Pattern-maker. 
 
 “ This is an excellent book, and should be in the hands of all who are interested in the con¬ 
 struction and design of medium-sized stationary engines. . . . A careful study of its contents and 
 the arrangement of the sections leads to the conclusion that there is probably no other book like it 
 in this country. The volume aims at showing the results of practical experience, and it certainly 
 may claim a complete achievement of this idea."— Nature. 
 
 “ There can be no question as to its value. We cordially commend it to all concerned in the 
 •design and construction of the steam engine.”— Mechanical World. 
 
 BOILER AND FACTORY CHIMNEYS. 
 
 Their Draught-Power and Stability. With a chapter on Lighning Conductors. 
 
 By Robert Wilson, A.I.C.E., Author of “ A Treatise on Steam Boilers,” &c. 
 Crown 8vo, cloth ........... 3/6 
 
 “ A valuable contribution to the literature of scientific building."— The Builder. 
 
 BOILER MAKER’S READY RECKONER & ASSISTANT. 
 
 With Examples of Practical Geometry and Templating, for the Use of Platers, 
 Smiths, and Riveters. By John Courtney, Edited by D. K. Clark, 
 M.I.C.E. Third Edition, 480 pp., with 140 Illustrations. Fcap. 8vo . 710 
 
 “ No workman or apprentice should be without this book."— Iro?i Trade Circular. 
 
 REFRIGERATING & ICE=MAKING MACHINERY. 
 
 A Descriptive Treatise for the Use of Persons Employing Refrigerating 
 and Ice-Making Installations, and others. By A. J. Wallis-Tayler, 
 A.-M. Inst. C.E. With Illustrations. Crown 8vo, cloth. [JustPublished. 7/6 
 “Practical, explicit, and profusely illustrated."— Glasgoiu Herald. 
 
 “ We recommend the book, which gives the cost of various systems and illustrations showing 
 details of parts of machinery and general arrangements of complete installations."— Builder. 
 
 “ Maybe recommended as a useful description of the machinery, the processes, and of the 
 facts, figures, and tabulated physics of refrigerating. It is one of the best compilations on the 
 subject. '— Engineer. 
 
 HYDRAULIC MACHINERY. 
 
 A Practical Handbook on the Machinery Employed in the Concentration and 
 Transmission of Power. Ey G. Croydon Marks, A.M.I.C.E., A.M.I.M.E. 
 New Edition, Enlarged. Crown 8vo. [In the Press. 
 
 THE LOCOMOTIVE ENGINE AND ITS DEVELOPMENT. 
 
 A Popular Treatise on the Gradual Improvements made in Railway Engines 
 between 1803 and 1896. By Clement E. Stretton, C.E. Fifth Edition, 
 Enlarged. With 120 Illustrations. Crown 8vo, cloth. [Just Published. 3/6 
 “ Students of railway history and all who are interested in the evolution of the modern loco¬ 
 motive will find much to attract and entertain in this volume.”— The Times. 
 
 “The author of this work is well known to the railway world, and no one, probably, has a 
 better knowledge of the history and development of the locomotive. The volume before us should 
 be of value to all connected with the railway system of this country.”— Nature. 
 
 ENGINEERING ESTIMATES, COSTS, AND ACCOUNTS. 
 
 A Guide to Commercial Engineering. With numerous examples of Estimates 
 and Costs of Millwright Work, Miscellaneous Productions, Steam Engines and 
 Steam Boilers; and a Section on the Preparation of Costs Accounts. By 
 A General Manager. Second Edition. 8vo, cloth. [Just Published. 12/0 
 “ This is an excellent and very useful book, covering subject-matter in constant requisition in 
 ■every factory and workshop. . . . The book is invaluable, not only to the young engineer, but 
 also to the estimate department of every works."— Builder. 
 
 “ We accord the work unqualified praise. The information is given in a plain, straightforward 
 manner, and bears throughout evidence of the intimate practical acquaintance of the author with 
 every phase of commercial engineering.”— Mechanical World. 
 
6 
 
 CROSBY LOCKWOOD &> SON'S CATALOGUE. 
 
 PLATING AND BOILER MAKING. 
 
 A Practical Handbook for Workshop Operations. By Joseph G. Horner, 
 
 A.M.I.M.E. (“ Foreman Pattern Maker”), Author of “ Pattern Making," &c. 
 
 380 pp. with 338 Illustrations. Crown 8vo, cloth. [Just Published. 7 6 
 “ The latest production from the pen of this writer is characterised by that evidence of close 
 acquaintance with workshop methods which will render the book exceedingly acceptable to the 
 practical hand. We have no hesitation in commending the work as a serviceable and practical 
 handbook on a subject which has not hitherto received much attention from those qualified to deal 
 with it in a satisfactory manner ."—Mechanical JI orId. 
 
 PATTERN MAKING. 
 
 A Practical Treatise, embracing the Main Types of Engineering Construction, 
 and including Gearing, both Hand and Machine-made, Engine Work, Sheaves 
 and Pulleys, Pipes and Columns, Screws, Machine Parts, Pumps and Cocks, 
 the Moulding of Patterns in Loam and Greensand, &c., together with the 
 methods of estimating the weight of Castings; to which is added an Appendix 
 of Tables for Workshop Reference. By Joseph G. Horner, A.M.I.M.E. 
 (“ Foreman Pattern Maker”). Second Edition, thoroughly Revised and much 
 Enlarged. With 450 Illustrations. Crown 8vo, cloth . . . - 7/6 
 
 “A well-written technical guide, evidently written by a man who understands and has prac¬ 
 tised what he has written about. . . . AVe cordially recommend it to engineering students, young 
 journeymen, and others desirous of being initiated into the mysteries of pattern-making."— Builder. 
 
 “ More than 400 illustrations help to explain the text, which is, however, always clear and ex¬ 
 plicit, thus rendering the work an excellent vade viccuvi for the apprentice who desires to become- 
 master of his trade.”— English Mechanic. 
 
 MECHANICAL ENGINEERING TERMS 
 
 (Lockwood’s Dictionary of). Embracing those current in the Drawing Office, 
 Pattern Shop, Foundry, Fitting, Turning, Smiths’, and Boiler Shops, &c., &c. 
 Comprising upwards of 6,000 Definitions. Edited by Joseph G. Horner, 
 A.M.I.M.E. (“Foreman Pattern Maker”), Author of “ Pattern Making,” &c. 
 Second Edition, Revised, with Additions. Crown 8vo, cloth . . - 7/6 
 
 “J u st the sort of handy dictionary required by the various trades engaged in mechanical en¬ 
 gineering. The practical engineering pupil will find the book of great value in his studies, and every 
 foreman engineer and mechanic should have a copy."— Building Ncu'S. 
 
 “ Not merely a dictionary, but, to a certain extent, also a most valuable guide. It strikes us 
 as a happy idea to combine with a definition of the phrase useful information on the subject of 
 which it treats.”— Machinery Market. 
 
 TOOTHED GEARING. 
 
 A Practical Handbook for Offices and Workshops. By Joseph Horner, 
 A.M.I.M.E. (“ Foreman Pattern Maker”), Author of “ Pattern Making,” &c. 
 
 With 184 Illustrations. Crown 8vo, cloth. 6/0 
 
 “ We must give the book our unqualified praise for its thoroughness of treatment, and we can 
 heartily recommend it to all interested as the most practical book on the subject j r et written."— 
 Mechanical World. 
 
 FIRES, FIRE=ENGINES, & FIRE BRIGADES. 
 
 With a History of Fire-Engines, their Construction, Use, and Manage¬ 
 ment ; Remarks on Fire-proof Buildings, and the Preservation of Life from 
 Fire; Statistics of the Fire Appliances in English Towns; Foreign Fire 
 Systems ; Hints on Fire-Brigades, &c., &c. By Charles F. T. Young, C.E. 
 With Illustrations, 544 pp. Demy 8vo, cloth . . . . . 4 s. 
 
 “ To such of our readers as are interested in the subject of fires and fire apparatus, we can 
 most heartily commend this book. It is really the only English work we now have upon the sub- 
 j ect."— Engineering. 
 
 MOTOR CARS FOR COMMON ROADS. 
 
 By A. J. Wallis-Tayler, Assoc. Memb. Inst. C.E., Author of “ Modern- 
 Cycles, ” &c. Including Early and Recent Examples of Steam Road Carriages, 
 Internal Combustion or Explosive Engine Carriages, Electric Motor Carriages, 
 Miscellaneous Motor Cars, Auto-Car Bill, Rules and Regulations, &c. With 
 numerous Illustrations. Crown 8vo, cloth. [Just Published. 4/6 
 
MECHANICAL ENGINEERING, 6-c. 
 
 7 
 
 STONE “WORKING MACHINERY. 
 
 A Manual dealing with the Rapid and Economical Conversion of Stone. With 
 Hints on the Arrangement and Management of Stone Works. By M. Povvis 
 Bale, M.I.M.E. Second Edition, enlarged. With Illustrations. Crown 8vo, 
 cloth. [Just Published. 9/0 
 
 “ The book should be in the hands of every mason or student of stonework."— Colliery 
 Guardian. 
 
 “ A capital handbook for all who manipulate stone for building or ornamental purposes.”— 
 Machinery Market. 
 
 PUMPS AND PUMPING. 
 
 A Handbook for Pump Users. Being Notes on Selection, Construction, and 
 Management. By M. Powis Bale, M.I.M.E. Third Edition, Revised. 
 Crown 8vo, cloth. [Just Published. 2 /6 
 
 “The matter is set forth as concisely as possible. In fact, condensation rather than diffuse¬ 
 ness has been the author’s aim throughout; yet he does not seem to have omitted anything likely to 
 be of use." —Journal of Gas Lighting. 
 
 “ Thoroughly practical and simply and clearly written.”— Glasgow Herald 
 
 MILLING MACHINES AND PROCESSES. 
 
 A Practical Treatise on Shaping Metals by Rotary Cutters. Including 
 Information on Making and Grinding the Cutters. By Paul N. Hasluck, 
 Author of “ Lathe-Work.” 352 pp. With upwards of 300 Engravings. Large 
 crown 8vo, cloth ........... 1 2/6 
 
 “ A new departure in engineering literature. . . . We can recommend this work to all in¬ 
 terested in milling machines ; it is what it professes to be—a practical treatise.”— Engineer. 
 
 “ A capital and reliable book which will no doubt be of considerable service both to those 
 who are already acquainted with the process as well as to those who contemplate its adoption.”— 
 Industries. 
 
 LATH E=WORK. 
 
 A Practical Treatise on the Tools, Appliances, and Processes employed in 
 the Art of Turning. By Paul N. Hasluck. Fifth Edition. Crown 8vo, 
 cloth ............. 5/0 
 
 “ Written by a man who knows net only how work ought to be done, but who also knows how 
 to do it, and how to convey his knowledge to others. To all turners this book would be valuable.”— 
 E ngin ee ring. 
 
 “ We can safely recommend the work to young engineers. To the amateur it will simply be 
 invaluable. To the student it will convey a great deal of useful information. "— Engineer. 
 
 SCREW=TH READS, 
 
 And Methods of Producing Them. With numerous Tables and complete 
 Directions for using Screw-Cutting Lathes. By Paul N. Hasluck, Author 
 of “Lathe-Work,” &c. With Seventy-four Illustrations. Fourth Edition, 
 Re-written and Enlarged. Waistcoat-pocket size . . . . * 1/6 
 
 “ Full of useful information, hints and practical criticism. Taps, dies, and screwing tools 
 generally are illustrated and their actions described." —Mechanical World. 
 
 “ It is a complete compendium of all the details of the screw-cutting lathe ; in fact a multum - 
 in-parvo on all the subjects it treats upon." —Carpeiiter and Builder. 
 
 TABLES AND MEMORANDA FOR ENGINEERS, 
 
 MECHANICS, ARCHITECTS, BUILDERS, &c. 
 
 Selected and Arranged by Francis Smith. Sixth Edition, Revised, including 
 Electrical Tables, Formulae, and Memoranda. Waistcoat-pocket size, 
 limp leather. [Just Published. 1 1 Q 
 
 “ It would, perhaps, be as difficult to make a small pocket-book selection of notes and formulae 
 to suit ALL engineers as it would be to make a universal medicine ; but Mr. Smith's waistcoat- 
 pocket collection may be looked upon as a successful attempt.”— Engineer. 
 
 “ The best example we have ever seen of 270 pages of useful matter packed into the dimen¬ 
 sions of a card-case."— Building News. “ A veritable pocket treasury of knowledge."— Iron. 
 
 POCKET GLOSSARY OF TECHNICAL TERMS. 
 
 English-French, French-English ; with Tables suitable for the Architectural, 
 Engineering, Manufacturing, and Nautical Professions. By John James 
 Fletcher, Engineer and Surveyor. Second Edition, Revised and Enlarged, 
 
 200 pp. Waistcoat-pocket size, limp leather. 1/6 
 
 “ It is a very great advantage for readers and correspondents in France and England to have 
 so large a number of the words relating to engineering and manufacturers collected in a lilliputian 
 volume. The little book will be useful both to students and travellers ."—Architect. 
 
 “ The glossary of terms is very complete, and many of the Tables are new and well arranged. 
 We cordially commend the book.”— Mechanical IVorld. 
 
CROSBY LOCKWOOD &■ SON'S CATALOGUE. 
 
 THE ENGINEER’S YEAR BOOK FOR 1897. 
 
 Comprising Formulae, Rules, Tables, Data and Memoranda in Civil, Mechanical 
 Electrical, Marine and Mine Engineering. By H. R. Kempe, A.M. Inst. C.E., 
 M.I.E.E., Technical Officer of the Engineer-in-Chief’s Office, General Post 
 Office, London, Author of “A Handbook of Electrical Testing.” “The 
 Electrical Engineer’s Pocket-Book,” &c. With about 850 Illustrations, specially 
 Engraved for the work. Crown 8vo, 670 pp., leather. [ Just Published. 8/0 
 “ Represents an enormous quantity of work, and forms a desirable book of reference ."—The 
 Engineer. 
 
 “The volume is distinctly in advance of most similar publications in this country."— 
 Engineering. 
 
 “ This valuable and well-designed book of reference meets the demands of all descriptions of 
 engineers." —Saturday Review. 
 
 “Teems with up-to-date information in every branch of engineering and construction."— 
 Building News. 
 
 “The needs of the engineering profession could hardly be supplied in a more admirable, 
 complete and convenient form. To say that it more than sustains all comparisons is praise of the 
 highest sort, and that may justly be said of it.”— Mining Jozirnal. 
 
 “ There is certainly room for the newcomer, which supplies explanations and directions, as 
 well as formulae and tables. It deserves to become one of the most successful of the technical 
 annuals. ”— A rchitect. 
 
 “ Brings together with great skill all the technical information which an engineer has to use 
 day by day. It is in every way admirably equipped, and is sure to prove successful.”— Scotsi?ian. 
 
 " The up-to-dateness of Mr. Kempe's compilation is a quality that will not be lost on the busy 
 people for whom the work is intended.' —Glasgow Herald. 
 
 THE PORTABLE ENGINE. 
 
 A Practical Manual on its Construction and Management. For the use 
 of Owners and Users of Steam Engines generally. By William Dyson 
 
 Wansbrough. Crown 8vo, cloth. 3/6 
 
 “ This is a work of value to those who use steam machinery. . . . Should be read by every 
 one who has a steam engine, on a farm or elsewhere.” —Mark Lane Express. 
 
 “ We cordially commend this work to buyers and owners of steam engines, and to those who 
 have to do with their construction or use.” —Timber Trades Journal. 
 
 “ Such a general knowledge of the steam-engine as Mr. Wansbrough furnishes to the reader 
 should be acquired by all intelligent owners and others who use the steam engine."— Building News. 
 
 “ An excellent text-book of this useful form of engine. The ‘ Hints to Purchasers' contain a 
 good deal of common-sense and practical wisdom.” —English Mechanic. 
 
 IRON AND STEEL. 
 
 A Work for the Forge, Foundry, Factory, and Office. Containing ready, 
 useful, and trustworthy Information for Ironmasters and their Stock-takers ; 
 Managers of Bar, Rail, Plate, and Sheet Rolling Mills; Iron and Metal 
 Founders; Iron Ship and Bridge Builders; Mechanical, Mining, and Con¬ 
 sulting Engineers; Architects, Contractors, Builders, &c. By Charles Hoare, 
 Author of “ The Slide Rule,” &c. Ninth Edition. 32mo, leather . 6,0 
 
 “ For comprehensiveness the book has not its equal.”— Iron. 
 
 “ One of the best of the pocket books."— English Mechanic. 
 
 CONDENSED MECHANICS. 
 
 A Selection of Formulae, Rules, Tables, and Data for the Use of Engineering 
 Students, Science Classes, &c. In accordance with the Requirements of the 
 Science and Art Department. By W. G. Crawford Hughes, A.M.I.C.E. 
 Crown 8vo, cloth . . . . . . • • • • - 2/6 
 
 “ The book is well fitted for those who are either confronted with practical problems in 
 their work, or are preparing for examination and wish to refresh their knowledge by going through 
 their formulae again." —Marine Engineer. 
 
 “ It is well arranged, and meets the wants of those for whom it is intended.''—Railway Acws. 
 
 THE SAFE USE OF STEAM. 
 
 Containing Rules for Unprofessional Steam Users. By an Engineer. Seventh 
 
 Edition. Sewed. 6d. 
 
 “ If steam-users would but learn this little book by heart, boiler explosions would become 
 sensations by their rarity."— English Mechanic. 
 
 HEATING BY HOT WATER. 
 
 With Information and Suggestions on the best Methods of Heating Public, 
 Private and Horticultural Buildings. By Walter Jones. Second Edition. 
 With 96 Illustrations, crown 8vo, cloth . ... Net 2/6 
 
 “We confidently recommend all interested in heating by hot water to secure a copy of this 
 valuable littie treatise.”— The Plumber and Decorator. 
 
CIVIL ENGINEERING, SURVEYING, &c. 
 
 9 
 
 CIVIL ENGINEERING, SURVEYING, &c. 
 
 LIGHT RAILWAYS FOR THE UNITED KINGDOM, 
 
 INDIA, AND THE COLONIES. 
 
 A Practical Handbook setting forth the Principles on which Light Railways 
 should be Constructed, Worked, and Financed ; and detailing the Cost of 
 Construction, Equipment, Revenue and Working Expenses of Local Railways 
 already established in the above-mentioned countries, and in Belgium, France, 
 Switzerland, &c. By J. C. Mackay, F.G.S., A.M. Inst. C.E. Illustrated 
 with Plates and Diagrams. Medium 8vo, cloth. [Just Published. 15/0 
 
 "Mr. Mackay’s volume is clearly and concisely written, admirably arranged, and freely 
 illustrated. The book is exactly what has been long wanted. We recommend it to all interested 
 in the subject. It is sure to have a wide sale." —Railway News. 
 
 “Those who desire to have within reach general information concerning almost all the light 
 railway systems in the world will do well to buy Mr. Mackay's book.”— Engineer. 
 
 “This work appears very opportunely, when the extension of the system on a large scale to 
 England is at last being mooted. In its pages we find all the information that the heart of man can 
 desire on the subject. . . . every detail in its story, founded on the experience of other countries 
 and applied to the possibilities of England, is put before us.”— Spectator. 
 
 PRACTICAL TUNNELLING. 
 
 Explaining in detail Setting-out the Works, Shaft-sinking, and Heading-driving, 
 Ranging the Lines and Levelling underground, Sub-Excavating, Timbering 
 and the Construction of the Brickwork of Tunnels, with the amount of Labour 
 required for, and the Cost of, the various portions of the work. By Frederick 
 W. Simms, M. Inst. C.E. Fourth Edition, Revised and Further Extended, 
 including the most recent (1895) Examples of Sub-aqueous and other Tunnels, 
 by D. Kinnear Clark, M. Inst. C.E. Imperial 8vo, with 34 Folding Plates 
 and other Illustrations. Cloth. [Just Published. £2 2 s. 
 
 “ The present (1896) edition has been brought right up to date, and is thus rendered a work to 
 which civil engineers generally should have ready access, and to which engineers who have con¬ 
 struction work can hardly afford to be without, but which to the younger members of the profession 
 is invaluable, as from its pages they can learn the state to which the science of tunnelling has 
 attained.”— Railway News. 
 
 “The estimation in which Mr. Simms's book on tunnelling has been held for many years 
 cannot be more truly expressed than in the words of the late Prof. Rankine: ‘ The best source of 
 information on the subject of tunnels is Mr. F. W. Simms's work on Practical Tunnelling.’ ”— 
 A rchitect 
 
 THE WATER SUPPLY OF TOWNS AND THE CON= 
 
 STRUCTION OF WATER=WORKS. 
 
 A Practical Treatise for the Use of Engineers and Students of Engineering. 
 By W. K. Burton, A.M. Inst. C.E., Professor of Sanitary Engineering in the 
 Imperial University, Tokyo, Japan, and Consulting Engineer to the Tokyo 
 Water-works. With an Appendix on THE EFFECTS OF EARTH¬ 
 QUAKES ON WATER-WORKS, by Professor John Milne, F.R.S. 
 With numerous Plates and Illustrations. Super-royal 8vo, buckram . 25/0 
 
 I. Introductory. — II. Different Qualities of Water.— III. Quantity of 
 Water to be Provided.—IV. On Ascertaining whether a Proposed Source of 
 Supply is Sufficient.—V. On Estimating the Storage Capacity required 
 to ee Provided.—VI. Classification of Water-works.—VII. Impounding Reser¬ 
 voirs.—VIII. Earthwork Dams.—IX. Masonry Dams.—X. The Purification of 
 Water.—XI. Settling Reservoirs.—XII. Sand Filtration.—XIII. Purification 
 of Water by Action of Iron, Softening of Water by Action of Lime, Natural 
 Filtration.—XIV. Service or Clean Water Reservoirs—Water Towers—Stand 
 Pipes.—XV. The connection of Settling Reservoirs, Filter Beds and Service 
 Reservoirs.—XVI. pumping Machinery.—XVII. Flow of Water in Conduits— 
 Pipes and open Channels.—xviii. Distribution Systems.—XIX. special pro¬ 
 visions for the Extinction of Fire.—XX. Pipes for Water-works.—XXI. Pre¬ 
 vention of Waste of Water.—XXII. Various Applications used in Connection 
 with Water-works. 
 
 Appendix. By Prof. JOHN MILNE, F.R.S.—Considerations concerning the 
 Probable Effects of Earthquakes on Water-works, and the Special Pre¬ 
 cautions to be taken in Earthquake Countries. 
 
 “ The chapter upon filtration of water is very complete, and the details of construction well 
 illustrated. . . . The work should be specially valuable to civil engineers engaged in work in 
 Japan, but the interest is by no means confined to that locality."— Engineer. 
 
 “ We congratulate the author upon the practical commonsense shown in the preparation of 
 this work. . . . The plates and diagrams have evidently been prepared with great care, and 
 cannot fail to be of great assistance to the student.”— Buildei. 
 
 “ The whole art of water-works construction is dealt with in a clear and comprehensive fashion 
 in this handsome volume. . . . Mr. Burton's practical treatise shows in all its sections the fruit 
 
 of independent study and individual experience. It is largely based upon his own practice in the 
 branch of engineering of which it treats."— SaUirday Review. 
 
10 
 
 CROSBY LOCKWOOD & SON'S CATALOGUE. 
 
 THE WATER SUPPLY OF CITIES AND TOWNS. 
 
 By William Humber, A. M. Inst. C.E., and M. Inst. M.E., Author of “Cast 
 and Wrought Iron Bridge Construction,” &c., &c. Illustrated with 50 Double 
 Plates, 1 Single Plate, Coloured Frontispiece, and upwards of 250 Woodcuts, 
 and containing 400 pp. of Text. Imp. 4to, elegantly and substantially 
 
 half-bound in morocco .£6 6s. 
 
 List of Contents. 
 
 I. Historical Sketch of some of the means that have eeen adopted for 
 the Supply of Water to Cities and Towns.—II. Water and the Foreign Matter 
 usually associated with it.—III. Rainfall and Evaporation.—IV. Springs and 
 the Water-bearing Formations of various Districts.—V. measurement and 
 Estimation of the Flow of Water.—VI. on the Selection of the Source of 
 Supply.—vii. Wells.— vm. Reservoirs.—IX. The Purification of water.—X. 
 Pumps.—XI. pumping Machinery.—XII. Conduits.—XIII. Distribution of Water. 
 —XIV. Meters, Service Pipes, and House Fittings.—XV. The Law of Economy of 
 Water-works.—XVI. constant and intermittent Supply.— XVII. description of 
 Plates.—appendices, giving Tables of Rates of [Supply, Velocities, &c. t &c., 
 together with Specifications of several Works illustrated, among which 
 
 WILL BE FOUND : ABERDEEN, BlDEFORD, CANTERBURY, DUNDEE, HALIFAX, LAMBETH, 
 
 Rotherham, Dublin, and others. 
 
 “ The most systematic and valuable work upon water supply hitherto produced in English, or 
 in any other language. . . . Mr. Humber's work is characterised almost throughout by an 
 
 exhaustiveness much more distinctive of P'rench and German than of English technical treatises."— 
 Engineer. 
 
 RURAL WATER SUPPLY. 
 
 A Practical Handbook on the Supply of Water and Construction of Water¬ 
 works for small Country Districts. By Allan Greenwell, A.M.I.C.E., 
 and W. T. Curry, A.M.I.C.E., F.G.S. With Illustrations. Crown 8vo, 
 cloth. [Just Published. 5/0 
 
 “ We conscientiously recommend it as a very useful book for those concerned in obtaining 
 water for small districts, giving a great deal of practical information in a small compass."— Builder. 
 
 “ The volume contains valuable information upon all matters connected with water supply. 
 . . . It is full of details on points which are continually before water-works engineers."— 
 Nature. 
 
 HYDRAULIC TABLES, CO=EFFIC!ENTS, & FORMUL/E. 
 
 For Finding the Discharge of Water from Orifices, Notches, Weirs, Pipes, and 
 Rivers. With New Formulae, Tables, and General Information on Rain-fall, 
 Catchment-Basins, Drainage, Sewerage, Water Supply for Towns and Mill 
 Power. By John Neville, Civil Engineer, M.R.I.A. Third Edition, 
 revised, with additions. Numerous Illustrations. Crown 8vo, cloth . 14 - 0 
 
 “ It is, of all English books on the subject, the one nearest to completeness. . . . From 
 the good arrangement of the matter, the clear explanations and abundance of formulae, the carefully 
 calculated tables, and, above all, the thorough acquaintance with both theory and construction, 
 which is displayed from first to last, the book will be found to be an acquisition."— Architect. 
 
 HYDRAULIC MANUAL. 
 
 Consisting of Working Tables and Explanatory Text. Intended as a Guide in 
 Hydraulic Calculations and Field Operations. By Lowis D’A. Jackson, 
 Author of “Aid to Survey Practice,” “Modern Metrology,” &c. Fourth 
 
 Edition, Enlarged. Large crown 8vo, cloth. 1 6/0 
 
 “ The author has had a wide experience in hydraulic engineering and has been a careful 
 observer of the facts which have come under his notice, and from the great mass of material at his 
 command he has constructed a manual which may be accepted as a trustworthy guide to this 
 branch of the engineer’s profession.” — Engineering. 
 
 “ The most useful feature of this work is its freedom from what is superannuated, and its 
 thorough adoption of recent experiments; the text is in fact in great part a short account of the 
 great modern experiments."— Nature. 
 
 WATER ENGINEERING. 
 
 A Practical Treatise on the Measurement, Storage, Conveyance, and Utilisa¬ 
 tion of Water for the Supply of Towns, for Mill Power, and for other Purposes. 
 By C. Slagg, A. M. Inst. C.E. Second Edition. Crown 8vo, cloth . 7/6 
 As a small practical treatise on the water supply of towns, and on some applications of water¬ 
 power, the work is in many respects excellent." — Engineering. 
 
 “ The author has collated the results deduced from the experiments of the most eminent 
 authorities, and has presented them in a compact and practical form, accompanied by very clear 
 and detailed explanations. . . . The application of water as a motive power is treated very 
 carefully and exhaustively." — Builder. 
 
CIVIL ENGINEERING, SURVEYING, &c. 
 
 ir 
 
 MASONRY DAMS FROM INCEPTION TO COMPLETION. 
 
 Including numerous Formulas, Forms of Specification and Tender, Pocket 
 Diagram of Forces, &c. For the use of Civil and Mining Engineers. By 
 C. F. Courtney, M. Inst. C.E. 8vo, cloth. [Just Published. 9/0 
 
 RIVER BARS. 
 
 The Causes of their Formation, and their Treatment by “ Induced Tidal 
 Scour;” with a Description of the Successful Reduction by this Method of 
 the Bar at Dublin. By I. J. Mann, Assist. Eng. to the Dublin Port and Docks 
 Board. Royal 8vo, cloth. 7/6 
 
 “ We recommend all interested in harbour works—and, indeed, those concerned in the 
 improvements of rivers generally—to read Mr. Mann's interesting work on the treatment of river 
 bars.' — Engineer. 
 
 DRAINAGE OF LANDS, TOWNS AND BUILDINGS. 
 
 By G. D. Dempsey, C.E. Revised, with large Additions on Recent Prac¬ 
 tice in Drainage Engineering, by D. Kinnear Clark, M. Inst. C.E., 
 Author of “Tramways: their Construction and Working.” Cr. 8vo, cloth . 4/6 
 “ The new matter added to Mr. Dempsey's excellent work is characterised by the compre¬ 
 hensive grasp and accuracy of detail for which the name of Mr. D. K. Clark is a sufficient 
 voucher."— Athenceum. 
 
 TRAMWAYS: THEIR CONSTRUCTION AND WORKING. 
 
 Embracing a Comprehensive History of the System ; with an exhaustive 
 Analysis of the Various Modes of Traction, including Horse Power, Steam, 
 Cable Traction, Electric Traction, &c. ; a Description of the Varieties ol 
 Rolling Stock; and ample Details of Cost and Working Expenses. New 
 Edition, Thoroughly Revised, and Including the Progress recently made in 
 Tramway Construction, &c., &c. By D. Kinnear Clark, M. Inst. C.E. 
 With 400 Illustrations. 8vo, 780 pp., buckram. [Just Published. 28/0 
 “ Although described as a new edition, this book is really a new one, a large part of it, which 
 covers historical ground, having been re-written and amplified ; while the parts which relate to all 
 that has been done since 1882 appear in this edition only. It is sixteen years since the first edition 
 appeared, and twelve years since the supplementary volume to the first book was published. 
 After a lapse, then, of twelve years, it is obvious that the author has at his disposal a vast 
 quantity of descriptive and statistical information, with which he may, and has, produced a 
 volume of great value to all interested in tramway construction and working. The new volume is 
 one which will rank, among tramway engineers and those interested in tramway working, with his 
 world-famed bock on railway machinery.”— The Engineer , March 8 , 1395. 
 
 PRACTICAL SURVEYING. 
 
 A Text-Book for Students preparing for Examinations or for Survey-work in 
 the Colonies. By George W. Usill, A.M.I.C.E. With 4 Plates and up¬ 
 wards of 330 Illustrations. Fourth Edition, Revised and Enlarged. Including 
 Tables of Natural Sines, Tangents, Secants, &c. Crown 8vo, cloth 7/6 *> or, 
 on Thin Paper, bound in limp leather, gilt edges, rounded corners, for 
 
 pocket use. 12/0 
 
 “The best forms of instruments are described as to their construction, uses and modes 
 of employment, and there are innumerable hints on work and equipment such as the author, in 
 his experience as surveyor, draughtsman and teacher, has found necessary, and which the student 
 in his inexperience will find most serviceable.” — Engineer. 
 
 “ The latest treatise in the English language on surveying, and we have no hesitation i say¬ 
 ing that the student will find it a better guide than any of its predecessors. Deserves to be 
 recognised as the first book which should be put in the hands of a pupil of Civil Engineering.”— 
 A rchi ted. 
 
 AID TO SURVEY PRACTICE. 
 
 For Reference in Surveying, Levelling, and Setting-out; and in Route Sur¬ 
 veys of Travellers by Land and Sea. With Tables, Illustrations, and Records. 
 By Lowis D’A. Jackson, A.M.I.C.E. Second Edition, Enlarged. Large 
 
 crown 8vo, cloth. 12/6 
 
 “Mr. Jackson has produced a valuable vade-mecum for the surveyor. We can recommend 
 this book as containing an admirable supplement to the teaching of the accomplished surveyor.”— 
 Athenceum. 
 
 “ As a text-book we should advise all surveyors to place it in their libraries, and study well 
 the matured instructions afforded in its pages.” —Colliery Guardian. 
 
 “The author brings to his work a fortunate union of theory and practical experience which, 
 aided by a clear and lucid style of writing, renders the book a very useful one." — Builder. 
 
12 
 
 CROSBY LOCKWOOD 6 - SON'S CATALOGUE . 
 
 ENGINEER’S & MINING SURVEYOR’S FIELD BOOK. 
 
 Consisting of a Series of Tables, with Rules, Explanations of Systems, and 
 use of Theodolite for Traverse Surveying and plotting the work with minute 
 accuracy by means of Straight Edge and Set Square only ; Levelling with the 
 Theodolite, Casting-out and Reducing Levels to Datum, and Plotting Sections 
 in the ordinary manner; Setting-out Curves with the Theodolite by Tangential 
 Angles and Multiples with Right and Left-hand Readings of the Instrument; 
 Setting-out Curves without Theodolite on the System of Tangential Angles by 
 Sets of Tangents and Offsets ; and Earthwork Tables to 80 feet deep, calcu¬ 
 lated for every 6 inches in depth. By W. Davis Haskoli., C.E. With 
 numerous Woodcuts. Fourth Edition, Enlarged. Crown 8vo, cloth . 12 0 
 
 “ The book is very handy ; the separate tables of sines and tangents to every minute will make 
 it useful for many other purposes, the genuine traverse tables existing all the same."— Athenaum. 
 
 “ Every person engaged in engineering field operations will estimate the importance of such 
 a work and the amount of valuable time which will be saved by reference to a set of reliable tables 
 prepared with the accuracy and fulness of those given in this volume.”— Railway News. 
 
 LAND AND MARINE SURVEYING. 
 
 In Reference to the Preparation of Plans for Roads and Railways; Canals, 
 Rivers, Towns’ Water Supplies; Docks and Harbours. With Description 
 and Use of Surveying Instruments. By W. Davis Haskoll, C.E. Second 
 Edition, Revised, with Additions. Large crown 8vo, cloth . . 90 
 
 “ This book must prove of great value to the student. We have no hesitation in recom¬ 
 mending it, feeling assured that it will more than repay a careful study." —Mechanical World. 
 
 “ A most useful and well-arranged book for the aid of the student. We can strongly recom¬ 
 mend it as a carefully-written and valuable text-book. It enjoys a well-deserved repute among 
 surveyors. ”— Builder. 
 
 “This volume cannot fail to prove of the utmost practical utility. It maybe safely recom¬ 
 mended to all students who aspire to become clean and expert surveyors.”— Mining Journal. 
 
 PRINCIPLES AND PRACTICE OF LEVELLING. 
 
 Showing its Application to Purposes of Railway and Civil Engineering in 
 the Construction of Roads ; with Mr. Telford’s Rules for the same. By 
 Frederick W. Simms, F.G.S., M. Inst. C.E. Seventh Edition, with the 
 addition of Law’s Practical Examples for Setting-out Railway Curves, and 
 Trautwine’s Field Practice of Laying-out Circular Curves. With 7 Plates 
 
 and numerous Woodcuts, 8vo, cloth.8 6 
 
 *** Trautwine on Curves may be had separate. 5/0 
 
 “ The text-book on levelling in most of our engineering schools and colleges."— Engineer. 
 “The publishers have rendered a substantial service to the profession, especially to the 
 younger members, by bringing out the present edition of Mr. Simms' useful work.”— Engineering. 
 
 AN OUTLINE OF THE METHOD OF CONDUCTING 
 
 A TRIGONOMETRICAL SURVEY. 
 
 For the Formation of Geographical and Topographical Maps and Plans, Mili¬ 
 tary Reconnaissance, LEVELLING, &c., with Useful Problems, Formulas, 
 and Tables. By Lieut.-General Frome, R.E. Fourth Edition, Revised and 
 partly Re-written by Major-General Sir Charles Warren, G.C.M.G., R.E. 
 With 19 Plates and 115 Woodcuts, royal 8vo, cloth . . . -16 0 
 
 “No words of praise from us can strengthen the position so well and so steadily maintained 
 by this work. Sir Charles Warren has revised the entire work, and made such additions as were 
 necessary to bring every portion of the contents up to the present date ."—Broad Arrow. 
 
 TABLES OF TANGENTIAL ANGLES AND MULTIPLES 
 
 FOR SETTING.OUT CURVES. 
 
 From 5 to 200 Radius. By A. Beazeley, M. Inst. C.E. 4th Edition. 
 Printed on 48 Cards, and sold in a cloth box, waistcoat pocket size. . 3 6 
 
 “ Each table is printed on a small card, which, being placed on the theodolite, leaves the 
 hands free to manipulate the instrument—no small advantage as regards the rapidity of work."— 
 Ejiginecr. 
 
 “ Very handy : a man may know that all his day's work must fall on two of these cards, which 
 he puts into his own card-case, and leaves the rest behind.”— Athenczum. 
 
 HANDY GENERAL EARTH=WORK TABLES. 
 
 Giving the Contents in Cubic Yards of Centre and Slopes of Cuttings and 
 Embankments from 3 inches to 80 feet in Depth or Height, for use with either 
 66 feet Chain or 100 feet Chain. By J. H. Watson Buck, M. Inst. C.E. 
 On a Sheet mounted in cloth case. [Just Published. 3/6 
 
CIVIL ENGINEERING, SURVEYING, &c. 
 
 13 
 
 EARTHWORK TABLES. 
 
 Showing the Contents in Cubic Yards of Embankments, Cuttings, &c., of 
 Heights or Depths up to an average of 80 feet. By Joseph Broadbent, C.E., 
 and Francis Campin, C.E. Crown 8 vo, cloth ... . 5,0 
 
 “ The way in which accuracy is attained, by a simple division of each cross section into three 
 elements, two in which are constant and one variable, is ingenious ."—Athence uni. 
 
 A MANUAL ON EARTHWORK. 
 
 By Alex. J. S. Graham, C.E. With numerous Diagrams. Second Edition. 
 i 8 mo, cloth.. 2/6 
 
 THE CONSTRUCTION OF LARGE TUNNEL SHAFTS. 
 
 A Practical and Theoretical Essay. By J. H. Watson Buck, M. Inst. C.E., 
 Resident Engineer, L. and N. W. R. With Folding Plates, 8 vo, cloth 12 0 
 “ Many of the methods given are of extreme practical value to the mason, and the observa¬ 
 tions on the form of arch, the rules for ordering the stone, and the construction of the templates, 
 will be found of considerable use. We commend the book to the engineering profession.”— 
 Building News. 
 
 “ Will be regarded by civil engineers as of the utmost value, and calculated to save much 
 time and obviate many mistakes .”—Colliery Guardian. 
 
 CAST & WROUGHT IRON BRIDGE CONSTRUCTION 
 
 (A Complete and Practical Treatise on), including Iron Foundations. In 
 Three Parts.—Theoretical, Practical, and Descriptive. By William Humber, 
 A. M. Inst. C.E., and M. Inst. M.E. Third Edition, revised and much im¬ 
 proved, with 115 Double Plates (20 of which now first appear in this edition), 
 and numerous Additions to the Text. In 2 vols., imp. 4 to, half-bound in 
 
 morocco .... . £6 16s. 8d. 
 
 “A very valuable contribution to the standard literature of civil engineering. In addition to 
 elevations, plans, and sections, large scale details are given, v/hich very much enhance the 
 instructive worth of those illustrations .”—Civil Engineer and Architect's journal. 
 
 “ Mr. Humber's stately I'olumes, lately issued—in which the most important bridges 
 erected during the last five years, under the direction of the late Mr. Brunei, Sir W. Cubitt, 
 Mr. Hawkshaw, Mr. Page, Mr. Fowler, Mr. Hemans, and others among our most eminent 
 engineers, are drawn and specified in great detail.”— Engineer. 
 
 ESSAY ON OBLIQUE BRIDGES 
 
 (Practical and Theoretical). With 13 large Plates. By the late George 
 Watson Buck, M.I.C.E. Fourth Edition, revised by his Son, J. H. Watson 
 Buck, M.I.C.E. ; and with the addition of Description to Diagrams for 
 Facilitating the Construction of Oblique Bridges, by W. H. Barlow, M.I.C.E. 
 Royal 8 vo, cloth ........... 1 2 0 
 
 “ The standard text-book for all engineers regarding skew arches is Mr. Buck's treatise, 
 and it would be impossible to consult a better."— Engineer. 
 
 "Mr. Buck's treatise is recognised as a standard text-book, and his treatment has divested 
 the subject of many of the intricacies supposed to belong to it. As a guide to the engineer and 
 architect, on a confessedly difficult subject, Mr. Buck's work is unsurpassed .”—Building News. 
 
 THE CONSTRUCTION OF OBLIQUE ARCHES 
 
 (A Practical Treatise on). By John Hart. Third Edition, with Plates. 
 Imperial 8 vo, cloth ........... 8/0 
 
 GRAPHIC AND ANALYTIC STATICS. 
 
 In their Practical Application to the Treatment of Stresses in Roofs, Solid 
 Girders, Lattice, Bowstring, and Suspension Bridges, Braced Iron Arches and 
 Piers, and other Frameworks. By R. Hudson Graham, C.E. Containing 
 Diagrams and Plates to Scale. With numerous Examples, many taken from 
 existing Structures. Specially arranged for Class-work in Colleges and 
 Universities. Second Edition, Revised and.Enlarged. 8 vo, cloth . 16/0 
 
 "Mr. Graham's book will find a place wherever graphic and analytic statics are used or 
 studied."— Engineer. 
 
 “ The work is excellent from a practical point of view, and has evidently been prepared 
 with much care. The directions for working are simple, and are illustrated by an abundance of 
 well-selected examples. It is an excellent text-book for the practical draughtsman.”— Athenceum. 
 
 WEIGHTS OF WROUGHT IRON & STEEL GIRDERS. 
 
 A Graphic Table for Facilitating the Computation of the Weights of Wrought 
 Iron and Steel Girders, &c., for Parliamentary and other Estimates. By 
 J. H. Watson Buck, M. Inst. C.E. On a Sheet.2/6 
 
14 
 
 CROSBY LOCKWOOD &■ SON'S CATALOGUE. 
 
 HANDY BOOK FOR THE CALCULATION OF STRAINS 
 
 In Girders and Similar Structures and their Strength. Consisting of Formulae 
 and Corresponding Diagrams, with numerous details for Practical Applica¬ 
 tion, &c. By William Humber, A. M. Inst. C.E., &c. Fifth Edition. 
 Crown 8vo, with nearly ioo Woodcuts and 3 Plates, cloth . . -716 
 
 “ The formulae are neatly expressed, and the diagrams good."— Athenaum. 
 
 “We heartily commend this really handy book to our engineer and architect readers."— 
 English Mechanic. 
 
 TRUSSES OF WOOD AND IRON. 
 
 Practical Applications of Science in Determining the Stresses, Breaking 
 Weights, Safe Loads, Scantlings, and Details of Construction. With Complete 
 Working Drawings. By William Griffiths, Surveyor, Assistant Master, 
 Tranmere School of Science and Art. Ohlong 8vo, cloth . . -4-6 
 
 “This handy little book enters so minutely into every detail connected with the con¬ 
 struction of roof trusses that no student need be ignorant of these matters."— Practical Engineer. 
 
 THE STRAINS ON STRUCTURES OF IRONWORK. 
 
 With Practical Remarks on Iron Construction. By F. W. Sheilds, M.I.C.E. 
 Svo, cloth. 5 0 
 
 A TREATISE ON THE STRENGTH OF MATERIALS. 
 
 With Rules for Application in Architecture, the Construction of Suspension 
 Bridges, Railways, &c. By Peter Barlow, F.R.S. A new Edition, revised 
 by his Sons* P. W. Barlow, F.R.S., and W. H. Barlow, F.R.S. ; to which 
 are added, Experiments by Hodgkinson, Fairbairn, and Kirkaldy ; and 
 Formulae for calculating Girders, &c. Arranged and Edited by Wm. Humber, 
 
 A. M. Inst. C.E. Demy 8vo, 400 pp., with 19 large Plates and numerous 
 Woodcuts, cloth . . . . . . . . . -180 
 
 “ Valuable alike to the student, tyro, and the experienced practitioner.it will always rank 
 an future as it has hitherto done, as the standard treatise on that particular subject."— Engineer. 
 
 “As a scientific work of the first class, it deserves a foremost place on the bookshelves of 
 every civil engineer and practical mechanic." —English Mechanic. 
 
 STRENGTH OF CAST IRON AND OTHER METALS. 
 
 By Thomas Tredgold, C.E. Fifth Edition, including Hodgkinson’s Experi¬ 
 mental Researches. 8vo, cloth . . . . . . . -12,0 
 
 SAFE RAILWAY WORKING. 
 
 A Treatise on Railway Accidents, their Cause and Prevention ; with a De¬ 
 scription of Modern Appliances and Systems. By Clement E. Strettox, 
 C.E., Vice-President and Consulting Engineer, Amalgamated Society of 
 Railway Servants. With Illustrations and Coloured Plates. Third Edition, 
 
 Enlarged. Crown 8vo, cloth.3 6 
 
 “A book for the engineer, the directors, the managers; and, in short, all who wish for 
 information on railway matters will find a perfect encyclopaedia in ‘Safe Railway Working. "— 
 Kailway Reviesu. 
 
 “We commend the remarks on railway signalling to all railway managers, especially where 
 a uniform code and practice is advocated. "— Herepath's Railway Journal. 
 
 “ The author may be congratulated on having collected, in a very convenient form, much 
 valuable information on the principal questions affecting the safe working of railways.” —Railway 
 Rngineer. 
 
 EXPANSION OF STRUCTURES BY HEAT. 
 
 By John Keily, C.E., late of the Indian Public Works Department. Crown 
 8 vo, cloth . . . . . . . . . . . . -3, 6 
 
 “ The aim the author has set before him, viz., to show the effects of heat upon metallic and 
 other structures, is a laudable one, for this is a branch of physics upon which the engineer or 
 architect can find but little reliable and comprehensive data in books."— Builder. 
 
 A TREATISE ON FIELD FORTIFICATION. 
 
 The Attack of Fortresses, Military Mining, and Reconnoitring. By Professor 
 Colonel I. S. Macaulay. Sixth Edition, crown 8vo, with separate Atlas of 
 12 Plates, cloth.1 2,0 
 
CIVIL ENGINEERING, SURVEYING, &c. 
 
 i5 
 
 RECORD OF THE PROGRESS OF MODERN 
 
 ENGINEERING. 
 
 Complete in Four Volumes, imperial 4to. half-morocco, price £1 2 1 2 s. 
 
 Each volume sold separately, as follows :— 
 
 First Series, Comprising Civil, Mechanical, Marine, Hydraulic, Railway, 
 Bridge, and other Engineering Works, &c. By William Humber, 
 A. M. Inst. C.E., &c. Imp. 4to, with 36 Double Plates, drawn to a large scale, 
 Photographic Portrait of John Hawkshaw, C.E., F.R.S., &c., and copious 
 descriptive Letterpress, Specifications, &c. Half-morocco . . £3 3 s. 
 
 List of the Plates and Diagrams. 
 
 Victoria Station and roof, L. B. & S. C. R. (8 plates) ; Southport Pier 
 (2 plates) ; Victoria Station and Roof, L. C. & D. and G. W. R. (6 plates) ; Roof 
 of cremorne Music Hall; Bridge over g. N. Railway: roof of Station, 
 Dutch Rhenish Rail. (2 plates); Bridge over the Thames, West London 
 Extension Railway (5 plates); armour plates: Suspension Bridge, Thames 
 
 4 PLATES); THE ALLEN ENGINE; SUSPENSION BRIDGE, AVON (3 PLATES); UNDER¬ 
 GROUND Railway (3 platesi. 
 
 HUMBER’S PROGRESS OF MODERN ENGINEERING. 
 
 Second Series. Imp. 4to, v/ith 3 Double Plates, Photographic Portrait of 
 Robert Stephenson, C.E., M.P., F.R.S., &c., and copious descriptive Letter- 
 
 press, Specifications, &c. Half-morocco. £3 3 s. 
 
 List of the Plates and Diagrams. 
 
 Birkenhead Docks, Low Water Basin (15 plates) ; Charing Cross Station 
 Roof, C. C, Railway (3 plates); Digswell Viaduct, Great Northern Railway; 
 Robbery Wood Viaduct, Great Northern Railway; Iron Permanent way; 
 Clydach Viaduct, Merthyr, Tredegar, and Abergavenny Railway; f.bbw 
 Viaduct, Merthyr, Tredegar, and Abergavenny Railway; College Wood 
 Viaduct, Cornwall railway; Dublin Winter Palace Roof (3 plates); Bridge 
 over the Thames, L. C. & D. Railway (6 plates); Albert Harbour, Greenock 
 (4 PLATES). 
 
 HUMBER’S PROGRESS OF MODERN ENGINEERING. 
 
 Third Series. Imp. 4to, with 40 Double Plates, Photographic Portrait of 
 J. R. M‘Clean, late Pres. Inst. C.E., and copious descriptive Letterpress, 
 Specifications, &c. Half-morocco. £3 3 s. 
 
 List of the Plates and Diagrams. 
 
 Main Drainage, Metropolis.— North Side.— Map showing Interception of 
 Sewers; Middle Level Sewer (2 plates); Outfall Sewer, Bridge over River 
 Lea 13 plates) ; Outfall Sewer, bridge over Marsh Lane, North Woolwich 
 Railway, and bow and Barking Railway Junction ; Outfall Sewer, Bridge over 
 Bow and Barking Railway (3 plates) ; Outfall Sewer, Bridge over East London 
 Water-works' Feeder (2 plates) ; Outfall Sewer reservoir (2 plates) ; Outfall 
 Sewer, tumbling Bay and Outlet ; Outfall Sewer, Penstocks. South Side.— 
 Outfall Sewer, Bermondsey Branch (2 plates) ; Outfall Sewer, Reservoir and 
 Outlet (4 plates) ; Outfall Sewer, Filth Hoist; Sections of Sewers (North and 
 South Sides). 
 
 Thames Embankment.—Section of River Wall ; Steamboat Pier, West¬ 
 minster (2 plates) ; Landing Stairs between Charing Cross and Waterloo 
 bridges ; York Gate (2 plates) ; Overflow and Outlet at Savoy Street Sewer 
 (3 plates); Steamboat Pier, Waterloo bridge (3 plates) ; Junction of Sewers, 
 Plans and Sections; Gullies, Plans and Sections; Rolling Stock; Granite 
 and Iron forts. 
 
 HUMBER’S PROGRESS OF MODERN ENGINEERING. 
 
 Fourth Series. Imp. 4to, with 36 Double Plates, Photographic Portrait of 
 John Fowler, late Pres. Inst. C.E., and copious descriptive Letterpress, Speci¬ 
 fications, &c. Half-morocco. £3 3 s. 
 
 List of the Plates and Diagrams. 
 
 Abbey Mills Pumping Station, Main Drainage, Metropolis (4 plates); 
 Barrow Docks (5 plates); Manquis Viaduct, Santiago and Valparaiso Railway, 
 ,(2 plates); Adam’s Locomotive, St. Helen's Canal Railway (2 plates); Cannon 
 Street Station Roof, Charing Cross Railway (3 plates); Road Bridge over 
 the River Moka (2 plates) ; Telegraphic Apparatus for Mesopotamia ; Viaduct 
 over the River Wye, Midland Railway (3 plates); St. Germans Viaduct, 
 Cornwall Railway (2 plates); Wrought-Iron cylinder for Diving Bell; 
 Millwall Docks (6 plates); Milroy’s Patent Excavator; metropolitan Dis¬ 
 trict Railway (6 plates) ; Harbours, Ports, and Breakwaters (3 plates). 
 
i6 
 
 CROSBY LOCKWOOD & SON'S CATALOGUE. 
 
 THE POPULAR WORKS OF MICHAEL REYNOLDS. 
 
 LOCOMOTIVE ENGINE DRIVING. 
 
 A Practical Manual for Engineers in Charge of Locomotive Engines. By 
 Michael Reynolds, Member of the Society of Engineers, formerly Loco¬ 
 motive Inspector, L. B. & S. C. R. Ninth Edition. Including a Key to 
 the Locomotive Engine. With Illustrations and Portrait of Author. 
 
 Crown 8vo, cloth . 46 
 
 “Mr. Reynolds has supplied a want, and has supplied it well. We can confidently recom¬ 
 mend the book not only to the practical driver, but to everyone who takes an interest in the 
 performance of locomotive engines." —The Engineer. 
 
 “ Mr. Reynolds has opened a new chapter in the literature of the day. This admirable 
 practical treatise, of the practical utility of which we have to speak in terms of warm commendation." 
 —A thenezum. 
 
 “ Evidently the work of one who knows his subject thoroughly."— Railway Service Gazette. 
 
 “ Were the cautions and rules given in the book to become part of the every-day working 
 of our engine-drivers, we might have fewer distressing accidents to deplore." — Scotsman. 
 
 STATIONARY ENGINE DRIVING. 
 
 A Practical Manual for Engineers in Charge of Stationary Engines. By 
 Michael Reynolds. Fifth Edition, Enlarged. With Plates and Woodcuts. 
 
 Crown 8vo, cloth.4- 6 
 
 “ The author is thoroughly acquainted with his subjects, and his advice on the various points 
 treated is clear and practical. . . . He has produced a manual which is an exceedingly useful 
 one for the class for whom it is specially intended.”— Engineering. 
 
 “Our author leaves no stone unturned. He is determined that his readers shall not only- 
 know something about the stationary engine, but all about it." — Engineer. 
 
 “An engineman who has mastered the contents of Mr. Reynolds’s book will require but 
 little actual experience with boilers and engines before he can be trusted to look after them."— 
 English Mechanic. 
 
 THE MODEL LOCOMOTIVE ENGINEER, 
 
 Fireman, and Engine-Boy Comprising a Historical Notice of the Pioneer 
 Locomotive Engines and their Inventors. By Michael Reynolds. Second 
 Edition, with Revised Appendix. With numerous Illustrations, and Portrait 
 of George Stephenson. Crown 8vo, cloth. [Just Published. 4/6 
 
 “ From the technical knowledge of the author, it will appeal to the railway man of to-day 
 more forcibly than anything written by Dr. Smiles. . . . The volume contains information of a 
 technical kind, and facts that every driver should be familiar with." —English Mechanic. 
 
 “ We should be glad to see this book in the possession of everyone in the kirtgdom who has 
 ever laid, or is to lay, hands on a locomotive engine.” — Iron. 
 
 CONTINUOUS RAILWAY BRAKES. 
 
 A Practical Treatise on the several Systems in Use in the United Kingdom : 
 their Construction and Performance. With copious Illustrations and numerous 
 Tables. By Michael Reynolds. Large crown 8vo, cloth . . . 9 0 
 
 “ A popular explanation of the different brakes. It will be of great assistance in forming 
 public opinion, and will be studied with benefit by those who take an interest in the brake.” — E?iglish 
 Mechanic. 
 
 “ Written with sufficient technical detail to enable the principal and relative connection of the 
 various parts of each particular brake to be readily grasped.” —Mechanical World. 
 
 ENGINE-DRIVING LIFE. 
 
 Stirring Adventures and Incidents in the Lives of Locomotive Engine- 
 Drivers. By Michael Reynolds. Third Edition. Crown 8vo, cloth . 1 6 
 “ From first to last perfectly fascinating. Wilkie Collins's most thrilling conceptions are 
 thrown into the shade by true incidents, endless in their variety, related in every page."— North 
 British Mail. 
 
 “Anyone who wishes to get a real insight into railway life cannot do better than read 
 ‘ Engine-Driving Life ' for himself, and if he once takes it up he will find that the author’s enthu¬ 
 siasm and real love of the engine-driving profession will carry him on until he has read every page.” 
 —Saturday Review. 
 
 THE ENGINEMAN’S POCKET COMPANION, 
 
 And Practical Educator for Enginemen, Boiler Attendants, and Mechanics. 
 By Michael Reynolds. With 45 Illustrations and numerous Diagrams. 
 Third Edition, Revised. Royal i8mo, strongly bound for pocket wear 3/6 
 “This admirable work is well suited to accomplish its object, being the honest workmanship 
 of a competent engineer.” —Glasgow Herald. 
 
 “A most meritorious work, giving in a succinct and practical form all the information an 
 engine-minder desirous of mastering the scientific principles of his daily calling would require.”— 
 The Miller. 
 
 “ A boon to those who are striving to become efficient mechanics.”— Daily Chronicle. 
 
MARINE ENGINEERING, NAVIGATION, &c. 
 
 i7 
 
 MARINE ENGINEERING, SHIPBUILDING, 
 NAVIGATION, &c. 
 
 THE NAVAL ARCHITECT’S AND SHIPBUILDER’S 
 
 POCKET=BOOK of Formula, Rules, and Tables, and Marine Engineer’s and 
 Surveyor's Handy Book of Reference. By Clement Mackrow, M.I.N.A. 
 Sixth Edition, Revised, 700 pp., with 300 Illustrations. Fcap., leather. 1 2 /© 
 
 Summary of Contents Signs and Symbols, Decimal Fractions.—Trigono¬ 
 metry.—Practical Geometry.—Mensuration.—Centres and Moments of Figures. 
 —Moments of Inertia and Radii of Gyration.—Algebraical Expressions for 
 Simpson's Rules.—Mechanical Principles.—Centre of Gravity.—Laws of Motion. 
 —Displacement, Centre of buoyancy.—Centre of Gravity of Ship's Hull- 
 Stability Curves and Metacentres.—Sea and Shallow-water Waves.—Rolling 
 of ships.—Propulsion and Resistance of Vessels.—Speed Trials.—Sailing, 
 Centre of Effort.—Distances down rivers, Coast Lines. —Steering and 
 Rudders of Vessels.—Launching Calculations and Velocities.—Weight of 
 Material and Gear.—Gun Particulars and Weight.—Standard gauges.— 
 Riveted Joints and Riveting.—Strength and Tests of Materials.—Binding 
 and Shearing Stresses, &c. — Strength of Shafting, Pillars, Wheels, &c. 
 —hydraulic Data, &c. — Conic Sections, Catenarian Curves. — Mechanical 
 Powers, Work.—Board of Trade Regulations for boilers and engines.—Board 
 of Trade Regulations for Ships.—Lloyd's Rules for boilers.—Lloyd's Weight 
 of Chains.—Lloyd's Scantlings for Ships.—Data of engines and Vessels.— 
 Ships’ Fittings and Tests.—Seasoning Preserving Timber.—Measurement of 
 Timber.—Alloys, Paints, Varnishes.—Data for Stowage.—Admiralty Trans¬ 
 port Regulations. —Rules for Horse-power, Screw Propellers, &c.— Per¬ 
 centages for Butt Straps, &c.— Particulars of Yachts.—masting and Rigging 
 Vessels.—Distances of Foreign Ports.—Tonnage Tables.—Vocabulary of 
 French and English Terms. — English Weights and Measures. — Foreign 
 Weights and Measures.—Decimal Equivalents.—Foreign money.—Discount 
 and Wages Tables.—Useful Numbers and Ready Reckoners.—Tables of 
 Circular Measures.—Tables of Areas of and Circumferences of Circles.— 
 Tables of Areas of Segments of Circles.—Tables of Squares and Cubes and 
 Roots of Numbers.—Tables of Logarithms of Numbers.—Tables of Hyper¬ 
 bolic Logarithms. —Tables of Natural Sines, Tangents, &c.—Tables of 
 Logarithmic Sines, Tangents, &c. 
 
 " In these days of advanced knowledge a work like this is of the greatest value. It contains 
 a vast amount of information. We unhesitatingly say that it is the most valuable compilation for its 
 specific purpose that has ever been printed. No naval architect, engineer, surveyor, or seaman, 
 wood or iron shipbuilder, can afford to be without this work."— Nautical Magazine. 
 
 “ Should be used by all who are engaged in the construction or design of vessels. . . . Will 
 be found to contain the most useful tables and formulae required by shipbuilders, carefully collected 
 from the best authorities, and put together in a popular and simple form. The book is one of 
 exceptional merit." — Engineer. 
 
 “ The professional shipbuilder has now, in a convenient and accessible form, reliable data for 
 solving many of the numerous problems that present themselves in the course of his work.”— Iron. 
 
 " There is no doubt that a pocket-book of this description must be a necessity in the ship¬ 
 building trade. . . . The volume contains a mass of useful information clearly expressed and 
 presented in a handy form."— Marine Engineer. 
 
 MARINE ENGINES AND STEAM VESSELS. 
 
 A Treatise on. By Robert Murray, C.E. Eighth Edition, thoroughly 
 Revised, with considerable Additions by the Author and by George 
 Carlisle, C.E., Senior Surveyor to the Board of Trade at Liverpool. 
 i2mo, cloth. 4/6 
 
 “Well adapted to give the young steamship engineer or marine engine and boiler maker a 
 general introduction into his practical work.”— Mechanical World. 
 
 “ We feel sure that this thoroughly revised edition will continue to be as popular in the future 
 as it has been in the past, as, for its size, it contains more useful information than any similar 
 treatise. ”— Industries. 
 
 “The information given is both sound and sensible, and well qualified to direct young sea¬ 
 going hands on the straight road to the extra chief's certificate. . . . Most useful to surveyors, 
 inspectors, draughtsmen, and all young engineers who take an interest in their profession.”— 
 Glasgow Herald 
 
 5 EA TERMS, PHRASES, AND WORDS 
 
 (Technical Dictionary of) used in the English and French Languages 
 (English-French, French-Englis”h). For the Use of Seamen, Engineers, Pilots, 
 Shipbuilders, Shipowners, and Ship-brokers. Compiled by W. Pirrie, late of 
 the African Steamship Company. Fcap. 8vo, cloth limp. [Just Published. 5/0 
 
 “ This volume will be highly appreciated by seamen, engineers, pilots, shipbuilders and ship¬ 
 owners. It will be found wonderfully accurate and complete.” — Scotsman. 
 
 “ A very useful dictionary, which has long been wanted by French and English engineers, 
 masters, officers, and others.”— Shippitig World. 
 
 L. 
 
CROSBY LOCKWOOD & SON'S CATALOGUE. 
 
 ELECTRIC SHIP LIGHTING. 
 
 A Handbook on the Practical Fitting and Running of Ships’ Electrical Plant, 
 for the Use of Shipowners and Builders, Marine Electricians and Sea-goin^ 
 Engineers in Charge. By J. W. Urquhart, Author of “Electric Light, 
 
 “ Dynamo Construction,” &c. With numerous Illustrations. Crown 8vo, 
 cloth. 7/6 
 
 MARINE ENGINEERS’ POCKET=BOOK. 
 
 Consisting of useful Tables and Formula;. By Frank ProctoK, A.I.N.A. 
 Third Edition. Royal 321110, leather, gilt edges, with strap . . . 4/0 
 
 “ We recommend it to our readers as going far to supply a long-felt want."— Naval Science 
 “ A most useful companion to all marine engineers ."—United Service Gazette . 
 
 ELEMENTARY ENGINEERING. 
 
 A Manual for Young Marine Engineers and Apprentices. In the Foi'm of 
 Questions and Answers on Metals, Alloys, Strength of Materials, Construction 
 and Management of Marine Engines and Boilers, Geometry, &c., &c. With 
 an Appendix of Useful Tables. By John Sherren Brewer, Government 
 Marine Surveyor, Hong Kong. Third Edition, small crown 8vo, cloth 1 1 Q 
 14 Contains much valuable information for the class for whom it is intended, especially in the 
 chapters on the management of boilers and engines."— Nautical Magazine. 
 
 “ A useful introduction to the more elaborate text-books."— Scotsman. 
 
 "To a student who has the requisite desire and resolve to attain a thorough knowledge 
 Mr. Brewer offers decidedly useful help."— Athenceum. 
 
 PRACTICAL NAVIGATION. 
 
 Consisting of The Sailor’s Sea-Book, by James Greenwood and W. H. 
 Rosser ; together with the requisite Mathematical and Nautical Tables for 
 the Working of the Problems, by Henry Law. C.E., and Professor J. R. 
 Young. Illustrated. i2mo, strongly half-bound ..... 7/0 
 
 MARINE ENGINEER’S DRAWING=BOOK. 
 
 Adapted to the Requirements of the Board of Trade Examinations. By John 
 Lockie, C.E. With 22 Plates, Drawn to Scale. Royal 8vo, cloth . 3 6 
 
 “The student who learns from these drawings will have nothing to unlearn.”— Engineer. 
 
 44 The examples chosen arc essentially practical, and are such as should prove of service to 
 engineers generally, while admirably fulfilling their specific purpose."— Mechanical JVorld. 
 
 THE ART AND SCIENCE OF SAILMAKING. 
 
 By Samuel B. Sadler, Practical Sailmaker, late in the employment of 
 Messrs. Ratsey and Lapthorne, of Cowes and Gosport. With Plates and 
 other Illustrations. Small 4to, cloth ....... 2/6 
 
 44 This extremely practical work gives a complete education in all the branches of the manu¬ 
 facture, cutting out, roping, seaming, and goring. It is copiously illustrated, and will form a first- 
 rate text-book and guide ."—Portsmouth Times. 
 
 “The author of this work has rendered a distinct service to all interested in the art of 
 sailmaking. The subject of which he treats is a congenial one. Mr. Sadler is a practical sailmaker, 
 and has devoted years of careful observation and study to the subject; and the results of the 
 experience thus gained he has set forth in the volume before us."— Steamship. 
 
 CHAIN CABLES AND CHAINS. 
 
 Comprising Sizes and Curves of Links, Studs, &c., Iron for Cables and Chains, 
 Chain Cable and Chain Making, Forming and Welding Links, Strength of 
 Cables and Chains, Certificates for Cables, Marking Cables, Prices of Chain 
 Cables and Chains, Historical Notes, Acts of Parliament, Statutory Tests, 
 Charges for Testing, List of Manufacturers of Cables, &c., &c. By 
 Thomas W. Traill, F.E.R.N., M.Inst.C.E., Engineer-Surveyor-in-Chief, 
 Board of Trade, Inspector of Chain Cable and Anchor Proving Establishments, 
 and General Superintendent Lloyd’s Committee on Proving Establishments. 
 With numerous Tables, Illustrations, and Lithographic Drawings. Folio, 
 
 cloth, bevelled boards.. £2 2s. 
 
 “It contains a vast amount of valuable information. Nothing seems to be wanting to make it 
 a complete and standard work of reference on the subject .’’—Nautical Magazine. 
 
MINING AND METALLURGY. 
 
 19 
 
 MINING AND METALLURGY. 
 
 COLLIERY WORKING AND MANAGEMENT. 
 
 Comprising the Duties of a Colliery Manager, the Oversight and Arrange¬ 
 ment of Labour and Wages, and the different Systems of Working Coal 
 Seams. By H. F. Bulman and R. A. S. Redmayne. 350 pp., with 
 28 Plates and other Illustrations, including Underground Photographs. 
 Medium Svo, cloth. [Just Published. 1 5/0 
 
 “ This is, indeed, an admirable Handbook for Colliery Managers, in fact it is an indispensable 
 adjunct to a Colliery Manager’s education, as well as being a most useful and interesting work 
 on the subject for all who in any way have to do with coal mining. The underground photographs 
 are an attractive feature of the work, being very lifelike and necessarily true representations of the 
 scenes they depict.”— Colliery Guardian. 
 
 “ Mr. Bulman and Mr. Redmayne, who are both experienced Colliery Managers of great 
 literary ability, are to be congratulated on having supplied an authoritative work dealing with a side 
 of the subject of coal mining which has hitherto received but scant treatment. The authors 
 elucidate their text by 119 woodcuts and 28 plates, most of the latter being admirable reproductions 
 of photographs taken underground with the aid of the magnesium flash-light. These illustrations 
 are excellent.”— Nature. 
 
 INFLAMMABLE GAS AND VAPOUR IN THE AIR 
 
 (The Detection and Measurement of). By Frank Clowes, D.Sc., Lond., 
 F.I.C., Prof, of Chemistry in the University College, Nottingham. With a 
 Chapter on The Detection and Measurement of Petroleum Vapour 
 by Boverton Redwood, F.R.S.E., Consulting Adviser to the Corporation 
 of London under the Petroleum Acts. Crown 8vo, cloth. 
 
 [Just Published. Net. 5/0 
 
 “ Professor Clowes has given us a volume on a subject of much industrial importance . . 
 
 Those interested in these matters may be recommended to study this book, which is easy of compre¬ 
 hension and contains many good things.” —The Engineer. 
 
 “ A convenient summary of the work on which Professor Clowes has been engaged for some 
 considerable time. . . . It is hardly necessary to say that any work on these subjects with these 
 
 names on the title-page must be a valuable one, and one that no mining engineer—certainly no cpal 
 miner—can afford to ignore or to leave unread.”— Mining Journal. 
 
 MACHINERY FOR METALLIFEROUS MINES. 
 
 A Practical Treatise for Mining Engineers, Metallurgists, and Managers of 
 Mines. By E. Henry Davies, M.E., F.G.S. Crown 8vo, 580 pp., with 
 upwards of 300 Illustrations, cloth. [Just Published. 1 2/B 
 
 “Mr. Davies, in this handsome volume, has done the advanced student and the manager of 
 mines good service. Almost every kind of machinery in actual use is carefully described, and the 
 woodcuts and plates are good.”— Athenezuin. 
 
 “From cover to cover the work exhibits all the same characteristics which excite the confi¬ 
 dence and attract the attention of the student as he peruses the first page. • The work may safely 
 be recommended. By its publication the literature connected with the industry v/ill be enriched 
 and the reputation of its author enhanced.” —Mining Journal. 
 
 METALLIFEROUS MINERALS AND MINING. 
 
 By D. C. Davies, F.G.S., Mining Engineer, &c., Author of “A Treatise on 
 Slate and Slate Quarrying.” Fifth Edition, thoroughly Revised and much 
 Enlarged by his Son, E. Henry Davies, M.E., F.G.S. With about 150 
 Illustrations. Crown 8vo, cloth . ....... “| 2/0 
 
 “ Neither the practical miner nor the general reader, interested in mines, can have a better 
 book for his companion and his guide.”— Mining Journal. 
 
 “ We are doing our readers a service in calling their attention to this valuable work.”— 
 Mining World. 
 
 “Asa history of the present state of mining throughout the world this book has a real value, 
 and it supplies an actual want.”— Athenezum. 
 
 EARTHY AND OTHER MINERALS AND MINING. 
 
 By D. C. Davies, F.G.S., Author of “ Metalliferous Minerals,” & c. Third 
 Edition, Revised and Enlarged by his Son, E. Henry Davies, M.E., F.G.S. 
 
 With about 100 Illustrations. Crown 8vo, cloth. 1 2/0 
 
 “ We do not remember to have met with any English work on mining matters that contains 
 the same amount of information packed in equally convenient form.” — Academy. 
 
 “ We should be inclined to rank it as among the very best of the handy technical and trades 
 manuals*which have recently appeared.”— British Quarterly Review. 
 
 B 2 
 
20 
 
 CROSBY LOCKWOOD <S» SON'S CATALOGUE. 
 
 BRITISH MINING. 
 
 A Treatise on the History, Discovery, Practical Development, and Future 
 Prospects of Metalliferous Mines in the United Kingdom. By Robert 
 Hunt, F.R.S., late Keeper of Mining Records. Upwards of 950 pp., with 
 230 Illustrations. Second Edition, Revised. Super-royal 8vo, cloth £2 2s. 
 
 “ The book is a treasure-house of statistical information on mining subjects, and we know of 
 no other work embodying so great a mass of matter of this kind. Were this the only merit of 
 Mr. Hunt’s volume it would be sufficient to render it indispensable in the library of every one 
 interested in the development of the mining and metallurgical industries of this country."— 
 Atheneeum. 
 
 “ A mass of information not elsewhere available, and of the greatest value to those who may 
 be interested in our great mineral industries."— Engineer. 
 
 MINE DRAINAGE. 
 
 A Complete and Practical Treatise on Direct-Acting Underground Steam 
 Pumping Machinery, with a Description of a large number of the best known 
 Engines, their General Utility and the Special Sphere of their Action, the 
 Mode of their Application, and their merits compared with other forms of 
 Pumping Machinery. By Stephen Michell. 8vo, cloth . . 15/0 
 
 “ Will be highly esteemed by colliery owners and lessees, mining engineers, and students 
 generally who require to be acquainted with the best means of securing the drainage of mines. 
 It is a most valuable work, and stands almost alone in the literature of steam pumping machinery." 
 —Colliery Guardian. 
 
 “ Much valuable information is given, so that the book is thoroughly worthy of an extensive 
 circulation amongst practical men and purchasers of machinery." —Mining Journal. 
 
 THE PROSPECTOR’S HANDBOOK. 
 
 A Guide for the Prospector and Traveller in search of Metal-Bearing or other 
 Valuable Minerals. By J. W. Anderson, M.A. (Camb.), F.R.G.S., Author 
 of “ Fiji and New Caledonia.” Seventh Edition, thoroughly Revised and 
 much Enlarged. Small crown 8vo, cloth, 3, 6 ", or, leather, pocket-book form, 
 with tuck. [Just Published. 4 6. 
 
 “ Will supply a much-felt want, especially among Colonists, in whose way are so often thrown 
 many mineralogical specimens the value of which it is difficult to determine."— Engineer. 
 
 “ How to find commercial minerals, and how to identify them when they are found, are the 
 leading points to which attention is directed. The author has managed to pack as much practical 
 detail into his pages as would supply material for a book three times its size." —Mining Journal. 
 
 NOTES AND FORMULA FOR MINING STUDENTS. 
 
 By John Herman Merivale, M.A., Certificated Colliery Manager, Professor 
 of Mining in the Durham College of Science, Newcastle-upon-Tyne. Third 
 Edition, Revised and Enlarged. Small crown 8vo, cloth . . . 2/6 
 
 “ The author has done his work in a creditable manner, and has produced a book that will 
 be of service to students and those who are practically engaged in mining operations."— Engineer. 
 
 THE MINER’S HANDBOOK. 
 
 A Handy Book of Reference on the subjects of Mineral Deposits, Mining 
 Operations, Ore Dressing, &c. For the Use of Students and others interested 
 in Mining Matters. By John Milne, F.R.S., Professor of Mining in the 
 Imperial University of Japan. Revised Edition. Fcap. 8vo, leather . Y/6 
 
 “Professor Milne's handbook is sure to be received with favour by all connected with 
 mining, and will be extremely popular among students."— Athenceum. 
 
 POCKET=BOOK for MINERS and METALLURGISTS. 
 
 Comprising Rules, Formulae, Tables, and Notes for Use in Field and Office 
 Work. By F. Danvers Power, F.G.S., M.E. Fcap. 8vo, leather . 9/0 
 “This excellent book is an admirable example of its kind, and ought to find a large sale 
 amongst English-speaking prospectors and mining engineers.”— Engineering. 
 
 MINERAL SURVEYOR and VALUER’S GUIDE. 
 
 Comprising a Treatise on Improved Mining Surveying and the Valuation of 
 Mining Properties, with New Traverse Tables. By Wm. Lintern. Third 
 Edition, Enlarged. i2ino, cloth. 3/6 
 
MINING AND METALLURGY. 
 
 21 
 
 THE COLLIERY MANAGER’S HANDBOOK. 
 
 A Comprehensive Treatise on the Laying-out and Working of Collieries, 
 Designed as a Book of Reference for Colliery Managers, and for the Use of Coal 
 Mining Students preparing for First-class Certificates. By Caleb Pamely, 
 Mining Engineer and Surveyor ; Member of the North of England Institute of 
 Mining and Mechanical Engineers ; and Member of the South Wales Institute 
 of Mining Engineers. With nearly 700 Plans, Diagrams, and other Illustra¬ 
 tions. Third Edition, Revised and Enlarged, medium 8vo, about 900 pp. 
 
 Strongly bound. 5 s. 
 
 Summary of Contents:—Geology.—Search for Coal.—Mineral Leases 
 
 AND OTHER HOLDINGS.—SHAFT SINKING.—FITTING UP THE SHAFT AND SURFACE 
 
 arrangements.—Steam Boilers and their Fittings.—Timbering and Walling.— 
 Narrow Work and Methods of Working. — Underground Conveyance. — 
 Drainage.—The Gases met with in Mines; Ventilation.—On the Friction of 
 Air in Mines.—The Priestman Oil Engine; Petroleum and Natural Gas.— 
 Surveying and Planning.—Safety Lamps and Firedamp Detectors.—Sundry 
 and Incidental Operations and Appliances.—Colliery Explosions.—Miscel¬ 
 laneous Questions and Answers.'— Appendix: Summary of Report of h.M. 
 Commissioners on Accidents in Mines. 
 
 “ Mr. Pamely has not only given us a comprehensive reference book of a very high order, 
 suitable to the requirements of mining engineers and colliery managers, but has also provided 
 mining students with a class-book that is as interesting as it is instructive.”— Colliery Manager. 
 
 “ Mr. Pamely s work is eminently suited to the purpose for which it is intended, being clear, 
 interesting, exhaustive, rich in detail, and up to date, giving descriptions of the latest machines in 
 every department. A mining engineer could scarcely go wrong who followed this work.”— Colliery 
 Guardian. 
 
 “This is the most complete ‘all-round’ work on coal-mining published in the English 
 language. . . . No library of coal-mining books is complete without it."— Colliery Engineer 
 (Scranton, Pa., U.S.A.). 
 
 COAL & IRON INDUSTRIES of the UNITED KINGDOM. 
 
 Comprising a Description of the Coal Fields, and of the Principal Seams of 
 Coal, with Returns of their Produce and its Distribution, and Analyses of 
 Special Varieties. Also, an Account of the Occurrence of Iron Ores in Veins or 
 Seams; Analyses of each Variety; and a History of the Rise and Progress of 
 Pig Iron Manufacture. By Richard Meade. 8vo, cloth . . £1 8s. 
 
 “ Of this book we may unreservedly say that it is the best of its class which we have ever 
 met. ... A book of reference which no one engaged in the iron or coal trades should omit from 
 his library.”— Iron and Coal Trades Review. 
 
 coal and coal mining. 
 
 By the late Sir Warington W. Smyth, M.A., F.R.S., &c., Chief Inspector 
 of the Mines of the Crown. Seventh Edition, Revised and Enlarged. With 
 numerous Illustrations, i2mo, cloth ....... 3 /© 
 
 “ As an outline is given of every known coal-field in this and other countries, as well as of the 
 principal methods of wc racing, the book will doubtless interest a very large number of readers."— 
 Alining Jourjial. 
 
 ASBESTOS AND ASBESTIC. 
 
 Their Properties, Occurrence, and Use. By Robert H. Jones, F.S.A., 
 Mineralogist, Hon. Mem. Asbestos Club, Black Lake, Canada. With Ten 
 Collotype Plates and other Illustrations. Demy 8vo, cloth. [lust Published. “| B/O 
 “ An interesting and invaluable work ."—Colliery Guardian. 
 
 SUBTERRANEOUS surveying 
 
 (Elementary and Practical Treatise on), with and without the Magnetic Needle. 
 By Thomas Fenwick, Surveyor of Mines, and Thomas Baker, C.E. Illus¬ 
 trated. i2mo, cloth... 2/6 
 
 granites and our granite industries. 
 
 By George F. Harris, F.G.S., Membre de la Soci£t£ Beige de G^ologie, 
 Lecturer on Economic Geology at the Birkbeck Institution, &c. With Illus¬ 
 trations. Crown 8vo, cloth. 2/6 
 
 “ A clearly and well-written manual for persons engaged or interested in the granite industry.” 
 — Scotsman. 
 
22 
 
 CROSBY LOCKWOOD &> SON'S CATALOGUE. 
 
 THE METALLURGY OF GOLD. 
 
 A Practical Treatise on the Metallurgical Treatment of Gold-bearing Ores. 
 Including the Processes of Concentration, Chlorination, and Extraction by 
 Cyanide, and the Assaying, Melting, and Refining of Gold. By M. Eissler, 
 Mining Engineer and Metallurgical Chemist, formerly Assistant Assayer of the 
 U.S. Mint, San Francisco. Fourth Edition, Enlarged. With about 250 Illus¬ 
 trations and numerous Folding Plates and Working Drawings. Large crown 
 8vo, cloth. [Just Published. 16 0 
 
 " This book thoroughly deserves its title of a ‘ Practical Treatise.’ The whole process of gold 
 milling, from the breaking of the quartz to the assay of the bullion, is described in clear and orderly 
 narrative and with much, but not too much, fulness of detail ."—Saturday Rn>inu. 
 
 1 he work is a storehouse of information and valuable data, and we strongly recommend it 
 to all professional men engaged in the gold-mining industry .”—Milling Journal. 
 
 THE CYANIDE PROCESS OF GOLD EXTRACTION. 
 
 Including its Practical Application on the Witwatersrand Gold Fields in South 
 
 Africa. By M. Eissler, M.E., Author of “The Metallurgy of Gold,” &c. 
 
 With Diagrams and Working Drawings. 8vo, cloth. [Just Published. 7 IQ 
 
 "This book is just what was needed to acquaint mining men with the actual working of a 
 process which is not only the most popular, but is, as a general rule, the most successful for the 
 extraction of gold from tailings ."—Mining Journal. 
 
 “ The work will prove invaluable to all interested in gold mining, whether metallurgists or as 
 investors.*”— C/ieniical News. 
 
 THE METALLURGY OF SILVER. 
 
 A Practical Treatise on the Amalgamation, Roasting, and Lixiviation of Silver 
 Ores. Including the Assaying, Melting, and Refining of Silver Bullion. By 
 M. Eissler, Author of “The Metallurgy of Gold,” &c. Third Edition. 
 Crown 8vo, cloth. 10 6 
 
 "A practical treatise, an^, a technical work which we are convinced will supply a long-felt 
 want amongst practical men, and at the same time be of value to students and others indirectly 
 connected with the industries .”—Mining Journal. 
 
 “ From first to last the book is thoroughly sound and reliable .”—Colliery Guardian. 
 
 “ For chemists, practical miners, assayers, and investors alike we do not know of any work 
 on the subject so handy and yet so comprehensive ."—Glasgow Herald. 
 
 THE METALLURGY OF ARGENTIFEROUS LEAD. 
 
 A Practical Treatise on the .Smelting of Silver-Lead Ores and the Refining of 
 Lead Bullion. Including Reports on various Smelting Establishments and 
 Descriptions of Modern Smelting Furnaces and Plants in Europe and America. 
 By M. Eissler, M.E., Author of “ The Metallurgy of Gold,” &c. Crown 8vo, 
 400 pp., with 183 Illustrations, cloth. 1 2/6 
 
 " The numerous metallurgical processes, which are fully and extensively treated of, embrace 
 all the stages experienced in the passage of the lead from the various natural states to its issue from 
 the refinery as an article of commerce .”—Practical Engineer. 
 
 “ The present volume fully maintains the reputation of the author. Those who wish to obtain 
 a thorough insight into the present state of this industry cannot do better than read this volume, and 
 all mining engineers cannot fail to find many useful hints and suggestions in it."— Industries. 
 
 METALLURGY OF IRON. 
 
 By H. Bauerman, F.G.S., A.R.S.M. Sixth Edition, Revised and Enlarged. 
 i2mo, cloth ............ 5/0 
 
 THE IRON ORES of GREAT BRITAIN and IRELAND. 
 
 Their Mode of Occurrence, Age and Origin, and the Methods of Searching for 
 and Working Them. With a Notice of some of the Iron Ores of Spain. By 
 J. D. Kendall, F.G.S., Mining Engineer. Crown 8vo, cloth . . 16/0 
 
 “The author has a thorough practical knowledge of his subject, and has supplemented a 
 careful study of the available literature by unpublished information derived from his own observa¬ 
 tions The result is a very useful volume, which cannot fail to be of value to all interested in the 
 iron industry of the country." — Industries. 
 
ELECTRICITY, ELECTRICAL ENGINEERING, S-c. 23 
 
 ELECTRICITY, ELECTRICAL 
 ENGINEERING, &c. 
 
 SUBMARINE TELEGRAPHS. 
 
 Their History, Construction, ancl Working. By Charles Bright, F.R.S.E. 
 Super-royal 8vo, about 600 pp., fully Illustrated. [In the Press. 
 
 [To Subscribers before publication , £2 2s. net; after publication the price 
 will be raised to £3 3s. net.] 
 
 THE ELECTRICAL ENGINEER’S POCKET-BOOK. 
 
 Consisting of Modern Rules, Formulas, Tables, and Data. By H. R. Kempe, 
 M.Inst.E.E., A.M.Inst.C.E., Technical Officer Postal Telegraphs, Author of 
 “A Handbook of Electrical Testing,” “The Engineer’s Year-Book,” &c. 
 Second Edition, thoroughly Revised, with Additions. With numerous Illus¬ 
 trations. Royal 32mo, oblong, leather . . . . . . . g/O 
 
 “ There is very little in the shape of formulas or data which the electrician is likely to want in 
 a hurry which cannot be found in its pages ."—Practical Engineer. 
 
 “ A very useful book of reference for daily use in practical electrical engineering and its 
 various applications to the industries of the present day."— Iron. 
 
 “ It is the best book of its kind ."—Electrical Engineer. 
 
 “ The Electrical Engineer's Pocket-Book is a good one."— Electrician. 
 
 “ Strongly recommended to those engaged in the electrical industries .”—Electrical Review. 
 
 ELECTRIC LIGHT FITTING. 
 
 A Handbook for Working Electrical Engineers, embodying Practical Notes on 
 Installation Management. By J. W. Urquhart, Electrician, Author of 
 “Electric Light,” &c. With numerous Illustrations. Third Edition, 
 Revised, with Additions. Crown 8vo, cloth. [Just Published. 5/0 
 
 “ This volume deals with what may be termed the mechanics of electric lighting, and Is 
 addressed to men who are already engaged in the work, or are training for it. The work traverses 
 a great deal of ground, and may be read as a sequel to the same author's useful work on ‘ Electric 
 Light.' ”— Electrician. 
 
 “ This is an attempt to state in the simplest language the precautions which should be adopted 
 in installing the electric light, and to give information for the guidance of those who have to run the 
 plant when installed. The book is well worth the perusal of the workman, for whom it is written." 
 —Electrical Review. 
 
 “ Eminently practical and useful. . . . Ought to be in the hands of every one In charge of an 
 electric light plant .”—Electrical Engineer. 
 
 ELECTRIC LIGHT. 
 
 Its Production and Use, Embodying Plain Directions for the Treatment of 
 Dynamo-Electric Machines, Batteries, Accumulators, and Electric Lamps. 
 By J. W. Urquhart, C.E., Author of “Electric Light Fitting,” “Electro¬ 
 plating,” &c. Sixth Edition, carefully Revised, with Additions and 145 Illus¬ 
 trations. Crown 8vo, cloth. [Just Published. 7 IS 
 
 “ The whole ground of electric lighting is more or less covered and explained in a very clear 
 and concise manner ."—Electrical Review. 
 
 “ Contains a good deal of very interesting information, especially in the parts where the author 
 gives dimensions and working costs ."—Electrical Engineer. 
 
 “A vade-inecian of the salient facts connected with the science of electric lighting.”—. 
 Electrician. 
 
 “You cannot for your purpose have a better book than ‘Electric Light’ by Urquhart.”-^ 
 Engineer. 
 
 “ The book is by far the best that we have yet met with on the subject."-^ the)\ceim\. 
 
 DYNAMO CONSTRUCTION. 
 
 A Practical Handbook for the Use of Engineer?Constructor-s and Electricians? 
 in-Charge. Embracing Framework Building, Field Magnet and Armature 
 Winding and Grouping, Compounding, &c. With Examples of leading 
 English, American, and Continental Dynamos and Motors. By J. W. 
 Urquhart, Author of “Electric Light,” &c. Second Edition, Enlarged. 
 With 114 Illustrations. Crown 8vo, cloth . . . . . 7 IS 
 
 “ Mr. Urquhart's book is the first one which deals with these matters in such a way that the 
 engineering student can understand them. The book is very readable, and the author leads his 
 readers up to difficult subjects by reasonably simple tests ."—Engineering Review. 
 
 “ ‘ Dynamo Construction’ more than sustains the high character of the author's previous 
 publications. It is sure to be widely read by the large and rapidly-increasing number of practical 
 electr'cians ."—Glasgow Herald. 
 
 ** A book for which.4 demand has long existed .'"-^-Mechanical World 
 
24 
 
 CROSBY LOCKWOOD &■ SON'S CATALOGUE. 
 
 THE MANAGEMENT OF DYNAMOS. 
 
 A Handy Book of Theory and Practice for the Use of Mechanics, Engineers, 
 Students, and others in Charge of Dynamos. By G. W. Lummis Paterson. 
 With numerous Illustrations. Crown 8vo, cloth . . . . .3/6 
 
 “ An example which deserves to be taken as a model by other authors. The subject is treated 
 in a manner which any intelligent man who is fit to be entrusted with charge of an engine should 
 be able to understand. It is a useful book to all who make, tend, or employ electric machinery.” 
 —A rchitcct. 
 
 THE STANDARD ELECTRICAL DICTIONARY. 
 
 A Popular Dictionary of Words and Terms Used in the Practice of Electrical 
 Engineering. Containing upwards of 3,000 Definitions. By T. O'Conor 
 Sloane, A.M., Ph.D. Crown 8vo, 630 pp., 350 Illustrations, cloth . 7/6 
 
 “ The work has many attractive features in it, and is, beyond doubt, a well put together and 
 useful publication. The amount of ground covered may be gathered from the fact that in the index 
 about 5,000 references will be found .”—Electrical Review. 
 
 ELECTRIC SHI P= LIGHTING. 
 
 A Handbook on the Practical Fitting and Running of Ships’ Electrical Plant. 
 For the Use of Shipowners and Builders, Marine Electricians, and Seagoing 
 Engineers-in-Charge. By J. W. Urquhart, C.E. With 88 Illustrations, 
 
 Crown 8vo, cloth. 7/6 
 
 “The subject of ship electric lighting is one of vast importance, and Mr. Urquhart is to be 
 highly complimented for placing such a valuable work at the service of marine electricians."— The 
 Steamship. 
 
 ELECTRIC LIGHT FOR COUNTRY HOUSES. 
 
 A Practical Handbook on the Erection and Running of Small Installations, 
 with Particulars of the Cost of Plant and Working. By J. H. Knight. 
 Crown 8vo, wrapper . . . . . . . . . . . 1/0 
 
 “ Tfie book contains excellent advice and many practical hints for the help of those who wish 
 to light their own houses ."—Building News. 
 
 ELEMENTARY PRINCIPLES OF ELECTRIC LIGHTING. 
 
 By Alan A. Campbell Swinton, Associate I.E.E. Third Edition, Enlarged 
 and Revised. With 16 Illustrations. Crown 8vo, cloth . . . -1/6 
 
 “ Any one who desires a short and thoroughly clear exposition of the elementary principles of 
 electric lighting cannot do better than read this little work .”—Bradford Observer. 
 
 DYNAMIC ELECTRICITY AND MAGNETISM. 
 
 By Philip Atkinson, A.M., Ph.D., Author of “Elements of Static 
 Electricity,” &c. Crown 8vo, 417 pp., with 120 Illustrations, cloth . 10/6 
 
 THE ELECTRIC TRANSFORMATION OF POWER. 
 
 With its Application by the Electric Motor, including Electric Railway 
 
 r' _ t __ D._ D A A AT DU TV AD.’.U Til____ 
 
 Construction. By P. Atkinson, A.M., Ph.D. With 96 Illustrations. 
 Crown 8vo, cloth. 7/6 
 
 HOW TO MAKE A DYNAMO. 
 
 A Practical Treatise for Amateurs. Containing numerous Illustrations and 
 Detailed Instructions for Constructing a Small Dynamo to Produce the 
 Electric Light. By Alfred Crofts. Fifth Edition, Revised and Enlarged. 
 Crown 8vo, cloth. [Just Published. 2/0 
 
 “ The instructions given in this unpretentious little book are sufficiently clear and explicit to 
 enable any amateur mechanic possessed of average skill and the usual tools to be found in an 
 amateur’s workshop to build a practical dynamo machine.”— Electrician. 
 
 THE STUDENT’S TEXT=BOOK OF ELECTRICITY. 
 
 By H. M. Noad, F.R.S. Cheaper Edition. 650 pp., with 470 Illustrations. 
 Crown 8vo, cloth. 9/0 
 
ARCHITECTURE, BUILDING, &-c. 
 
 2 5 
 
 ARCHITECTURE, BUILDING, &c. 
 
 PRACTICAL BUILDING CONSTRUCTION. 
 
 A Handbook for Students Preparing for Examinations, and a Book of 
 Reference for Persons Engaged in Building. By John Parnell Allen, 
 Surveyor, Lecturer on Building Construction at the Durham College of 
 Science, Nevvcastle-on-Tyne. Second Edition, Revised and Enlarged. 
 Medium 8vo, 450 pp., with 1,000 Illustrations, cloth. [Just Published. 7/6 
 “ The most complete exposition of building construction we have seen. It contains all that is 
 necessary to prepare students for the various examinations in building construction.”— Building; 
 News. 
 
 “ The author depends nearly as much on his diagrams as on his type. The pages suggest 
 the hand of a man of experience in building operations—and the volume must be a blessing to 
 many teachers as well as to students."— The Architect. 
 
 “The work is sure to prove a formidable rival to great and small competitors alike, and 
 bids fair to take a permanent place as a favourite student's text-book. The large number of illus¬ 
 trations deserve particular mention for the great merit they possess for purposes of reference in 
 exactly corresponding to convenient scales."— Journal 0/ the Royal Institute of British Architects. 
 
 PRACTICAL MASONRY. 
 
 A Guide to the Art of Stone Cutting. Comprising the Construction, Setting 
 Out, and Working of Stairs, Circular Work, Arches, Niches, Domes, Penden- 
 tives, Vaults, Tracery Windows, &c., &c. For the Use of Students, Masons, 
 and other Workmen. By William R. Purchase, Building Inspector to the 
 Town of Hove. Royal 8vo, 134 pp., with 50 Lithographic Plates, comprising 
 nearly 400 separate Diagrams, cloth . . . . . . . - 7/6 
 
 “Mr. Purchase’s ‘ Practical Masonry' will undoubtedly be found useful to all interested in 
 this important subject, whether theoretically or practically. Most of the examples given are from 
 actual work carried out, the diagrams being carefully drawn. The book is a practical treatise on 
 the subject, the author himself having commenced as an operative mason, and afterwards acted as 
 foreman mason on many large and important buildings prior to the attainment of his present 
 position. It should be found of general utility to architectural students and others, as well as to 
 those to whom it is specially addressed."— Journal of the Royal Institute of British Architects. 
 
 “The author has evidently devoted much time and conscientious labour in the production of 
 his book, which will be found very serviceable to students, masons, and other workmen, while its 
 value is much enhanced by the capital illustrations, consisting of fifty lithographic plates, com¬ 
 prising about 400 diagrams.”— Illustrated Carpenter and Builder. 
 
 CONCRETE: ITS NATURE AND USES. 
 
 A Book for Architects, Builders, Contractors, and Clerks of Works. By 
 George L. Sutcliffe, A.R.I.B.A. 350 pp., with numerous Illustrations. 
 Crown 8vo, cloth.. . - 7/6 
 
 “ The author treats a difficult subject in a lucid manner. The manual fills a long-felt gap. 
 It is careful and exhaustive ; equally useful as a student’s guide and an architect’s book of 
 reference."— Journal of the Royal Institute of British A rchitects. 
 
 “There is room for this new book, which will probably be for some time the standard work 
 on the subject for a builder’s purpose.”— Glasgoiu Herald. 
 
 THE MECHANICS OF ARCHITECTURE. 
 
 A Treatise on Applied Mechanics, especially Adapted to the Use of Architects. 
 By E. W. Tarn, M.A., Author of “ The Science of Building,” &c. Second 
 Edition, Enlarged. Illustrated with 125 Diagrams. Crown 8vo, cloth 7/0 
 “The book is a very useful and helpful manual of architectural mechanics, and really contains 
 sufficient to enable a careful and painstaking student to grasp the principles bearing upon the 
 majority of building problems. . . . Mr. Tarn has added, by this volume, to the debt of 
 
 gratitude which is owing to him by architectural students for the many valuable works which he has 
 produced for their use."— The Builder. 
 
 “ The mechanics in the volume are really mechanics, and are harmoniously wrought in with 
 the distinctive professional matter proper to the subject. The diagrams and type are commendably 
 clear."— The Schoolmaster. 
 
 LOCKWOOD’S BUILDER’S PRICE BOOK for 1898. 
 
 A Comprehensive Handbook of the Latest Prices and Data for Builders, 
 Architects, Engineers, and Contractors. Re-constructed, Re-written, and 
 Greatly Enlarged. By Francis T. W. Miller. 800 closely-printed pages, 
 
 crown 8vo, cloth.4/0 
 
 “ This book is a very useful one, and should find a place in every English office connected 
 with the building and engineering professions.”— Industries. 
 
 ‘An excellent book of reference.”— Architect. 
 
 “ In its new and revised form this Price Book is what a work of this kind should be—compre¬ 
 hensive, reliable, well arranged, legible, and well bound.”— British Architect. 
 
26 
 
 CROSBY LOCKWOOD <S» SON'S CATALOGUE. 
 
 THE LONDON BUILDING ACT, 1894. 
 
 With the By-Laws and Regulations of the London County Council, and 
 Introduction, Notes, Cases, and Index. By Alex. J. David, B.A., LL.M., of 
 the Inner Temple, Barrister-at-Law. Crown 8vo, cloth . . -36 
 
 “To all architects and district surveyors and builders Mr. David’s manual will be welcome.” 
 —Building Neivs. 
 
 1 he volume will doubtless be eagerly consulted by the building fraternity .”—Illustrated 
 Carpenter and Builder 
 
 THE DESIGN OF BUILDINGS. 
 
 Being Elementary Notes on the Planning, Sanitation, and Ornamentive 
 Formation of Structures, based on Modern Practice. Illustrated with Nine 
 Folding Plates. By W. Woodley. 8vo, cloth.6 0 
 
 THE DECORATIVE PART of CIVIL ARCHITECTURE. 
 
 By Sir William Chambers, F.R.S. With Portrait, Illustrations, Notes, and 
 an Examination of Grecian Architecture, by Joseph Gwilt, F.S.A. 
 Revised and Edited by W. H. Leeds. 66 Plates, 4to, cloth . . 21 /O 
 
 A HANDY BOOK OF VILLA ARCHITECTURE. 
 
 Being a Series of Designs for Villa Residences in various Styles. With 
 Outline .Specifications and Estimates. By C. Wickes, Architect, Author of 
 “The Spires and Towers of England,” &c. 6i Plates, 4to, half-morocco, gilt 
 
 edges. £1 11s. 6 d. 
 
 “ The whole of the designs bear evidence of their being the work of an artistic architect, and 
 they will prove very valuable and suggestive." —Building News. 
 
 THE ARCHITECT’S GUIDE. 
 
 Being a Text-book of Useful Information for Architects, Engineers, Surveyors, 
 Contractors, Clerks of Works, &c., &c. By Frederick Rogers, Architect. 
 
 Third Edition. Crown 8vo, cloth . •. 3/6 
 
 “ As a text-book of useful informa: ion for architects, engineers, surveyors, See., it would be 
 hard to find a handier or more complete little volume.” —Standard 
 
 architectural perspective. 
 
 The whole Course and Operations of the Draughtsman in Drawing a Large 
 House in Linear Perspective. Illustrated by 43 Folding Plates. By F. O. 
 Ferguson. Second Edition, Enlarged. 8vo, boards .... 3/6 
 
 “ It is the most intelligible of the treatises on this ill-treated subject that I have met with."— 
 E. INGRESS Bell, Eso., in the R.I.B.A. Journal. 
 
 practical rules on drawing. 
 
 For the Operative Builder and Young Student in Architecture. By George 
 Pyne. 14 Plates, 4to, boards. 7/6 
 
 MEASURING AND VALUING ARTIFICER’S WORK. 
 
 (The Student’s Guide to the Practice of.) Containing Directions for taking 
 Dimensions, Abstracting the same, and bringing the Quantities into Bill, with 
 Tables of Constants for Valuation of Labour, and for the Calculation of Areas 
 and Solidities. Originally edited by E. Dobson, Architect. With Additions 
 by E. W. Tarn, M.A. Sixth Edition. With 8 Plates and 63 Woodcuts. 
 Crown 8vo, cloth. 7/6 
 
 “ This edition will be found the most complete treatise on the principles of measuring and 
 valuing artificers work that has yet been published.”— Building Ne 7 vs. 
 
 TECHNICAL GUIDE, MEASURER, and ESTIMATOR. 
 
 For Builders and Surveyors. Containing Technical Directions for Measuring 
 Work in all the Building Trades, Complete Specifications for Houses, Roads, 
 and Drains, and an Easy Method of Estimating the parts of a Building 
 collectively. By A. C. Beaton. Eighth Edition. Waistcoat-pocket size. 
 
 gilt edges . . .. 1/6 
 
 "No builder, architect, surveyor, or valuer should be without his ‘Reato x\.'"—Building 
 
 News. 
 
ARCHITECTURE, BUILDING, &-c. 
 
 2 7 
 
 CONSTRUCTIONAL IRON AND STEEL WORK. 
 
 As Applied to Public, Private, and Domestic Buildings. A Practical Treatise 
 for Architects, Students, and Builders. By F. Cam pin. Crown 8vo, cloth. 
 
 [Just Published. 3/6 
 
 “Any one who wants a book on ironwork, as employed in buildings for stanchions, columns, 
 and beams, will find the present volume to be suitable. The author has had long and varied 
 experience in designing this class of work. The illustrations have the character of working 
 drawings. This practical book may be counted a most valuable work .”—British Architect. 
 
 SPECIFICATIONS for PRACTICAL ARCHITECTURE. 
 
 A Guide to the Architect, Engineer, Surveyor, and Builder. With an Essay 
 on the Structure and Science of Modern Buildings. Upon the Basis of the 
 Work by Alfred Bartholomew, thoroughly Revised, Corrected, and greatly 
 added to by Frederick Rogers, Architect. Third Edition, Revised. 8vo, 
 
 cloth. 15/0 
 
 “ The work is too well known to need any recommendation from us. It is one of the books 
 with which every young architect must be equipped.”— Architect. 
 
 THE SCIENCE OF BUILDING. 
 
 An Elementary Treatise on the Principles of Construction. By E. Wyndham 
 Tarn, M.A., Architect. Third Edition, Revised and Enlarged, with 59 
 Engravings. Fcap. 8vo, cloth ......... 3 IQ. 
 
 “A very valuable book, which we strongly recommend to all students. ”— Builder. 
 
 THE HOUSE=OWNER’S ESTIMATOR. 
 
 Or, What will it Cost to Build, Alter, or Repair? A Price Book for Un¬ 
 professional People as well as the Architectural Surveyor and Builder. By 
 J. D. Simon. Edited by F. T. W. Miller, A.R.I.B.A. Fourth Edition. 
 Crown 8vo, cloth . . . . . . . . . . . 3 /S 
 
 “ In two years it will repay its cost a hundred times over.”— Field. 
 
 A BOOK ON BUILDING. 
 
 Civil and Ecclesiastical, including Church Restoration ; with the Theory of 
 Domes and the Great Pyramid, &c. By Sir Edmund Beckett, Bart., LL.D., 
 F.R.A.S. Second Edit. Fcap. 8vo, cloth ...... 4/6 
 
 “ A book which is always amusing and nearly always instructive ."—The Tunes. 
 
 SANITARY ARRANGEMENT OF DWELL!NG = HOUSES. 
 
 A Handbook for Householders and Owners of Houses. By A. J. Wallis- 
 Tayler, A.M.Inst.C.E. With Illustrations. Crown 8vo, cloth . 2/6 
 
 “This book will be largely read; it will be of considerable service to the public. It is well 
 arranged, easily read, and for the most part devoid of technical terms.”— Lancet. 
 
 VENTILATION. 
 
 A Text-book to the Practice of the Art of Ventilating Buildings. By W. P. 
 Buchan, R.P. i2mo, cloth. 3/6 
 
 "Contains a great amount of useful practical information as thoroughly interesting as it is 
 technically reliable .”—British Architect. 
 
 PLUMBING. 
 
 A Text-book to the Practice of the Art or Craft of the Plumber. By W. P. 
 Buchan, R.P. Seventh Edition, Enlarged. Crown 8vo, cloth . . 3/6 
 
 “ A text-book which may be safely put in the hands of every young plumber."— Builder. 
 
 PRACTICAL GEOMETRY. 
 
 For the Architect, Engineer, and Mechanic. Giving Rules for the Delineation 
 and Application of various Geometrical Lines, Figures, and Curves. By 
 E. W. Tarn, M.A., Architect. 8vo, cloth ...... 9/0 
 
 “No book with the same objects in view has ever been published in which the clearness of 
 the rules laid down and the illustrative diagrams have been so satisfactory.”— Scotsman. 
 
 THE GEOMETRY OF COMPASSES. 
 
 Or, Problems Resolved by the mere Description of Circles and the use of 
 Coloured Diagrams and Symbols. By Oliver Byrne. Coloured Plates. 
 Crown 8vo, cloth. , 3/6 
 
28 
 
 CROSBY LOCKWOOD &■ SON'S CATALOGUE. 
 
 CARPENTRY, TIMBER, &c. 
 
 THE ELEMENTARY PRINCIPLES OF CARPENTRY. 
 
 A Treatise on the Pressure and Equilibrium of Timber Framing, the Resistance 
 of Timber, and the Construction of Floors, Arches, Bridges, Roofs, Uniting 
 Iron and Stone with Timber, &c. To which is added an Essay on the Nature 
 and Properties of Timber, &c., with Descriptions of the kinds of Wood used 
 in Building; also numerous Tables of the Scantlings of Timber for different 
 purposes, the Specific Gravities of Materials, &c. By Thomas Tredgold, C.E. 
 With an Appendix of Specimens of Various Roofs of Iron and Stone, Illus¬ 
 trated. Seventh Edition, thoroughly Revised and considerably Enlarged by 
 E. Wyndham Tarn, M.A., Author of “ The Science of Building,” &c. 
 With 61 Plates, Portrait of the Author, and several Woodcuts. In One large 
 
 Vol., 4to, cloth. 25/0 
 
 “Ought to be in every architect's and every builder's library."— Builder. 
 
 “A work whose monumental excellence must commend it wherever skilful carpentry is 
 concerned. The author’s principles are rather confirmed than impaired by time. The additional 
 plates are of great intrinsic value.”— Building News. 
 
 WOODWORKING MACHINERY. 
 
 Its Rise, Progress, and Construction. With Hints on the Management of Saw 
 Mills and the Economical Conversion of Timber. Illustrated with Examples 
 of Recent Designs by leading English, French, and American Engineers. By 
 M. Powis Bale, A.M.Inst.C.E., M.I.M.E. Second Edition, Revised, 
 with large Additions, large crown 8vo, 440 pp., cloth .... 9/0 
 
 “ Mr. Bale is evidently an expert on the subject, and he has collected so much information 
 that his book is all-sufficient for builders and others engaged in the conversion of timber."— Architect. 
 
 “The most comprehensive compendium of wood-working machinery we have seen. The 
 author 'is a thorough master of his subject.”— Building News. 
 
 SAW MILLS. 
 
 Their Arrangement and Management, and the Economical Conversion of 
 Timber. By M. Powis Bale, A.M.Inst.C.E. Second Edition, Revised. 
 Crown 8vo, cloth. '[Just Published. “ 10/6 
 
 “ The administration of a large sawing establishment is discussed, and the subject examined 
 from a financial standpoint. Hencethe size, shape, order, and disposition of saw mills and the like 
 are gone into in detail, and the course of the timber is traced from its reception to its delivery in its 
 converted state. We could not desire a more complete or practical treatise.”— Builder. 
 
 THE CARPENTER’S NEW GUIDE. 
 
 Or, Book of Lines for Carpenters ; comprising all the Elementary Principles 
 essential for acquiring a knowledge of Carpentry. Founded on the late Peter 
 Nicholson’s standard work. A New Edition, Revised by Arthur Ashpitel, 
 F.S.A. Together with Practical Rules on Drawing, by George Pvne. 
 With 74 Plates, 4to, cloth. £1 1 s. 
 
 A PRACTICAL TREATISE ON HANDRAILING. 
 
 Showing New and Simple Methods for Finding the Pitch of the Plank, Drawing 
 the Moulds, Bevelling, Jointing-up, and Squaring the Wreath. By George 
 Collings. Second Edition, Revised and Enlarged, to which is added 
 A Treatise on Stair-building. With Plates and Diagrams . . 2/6 
 
 “ will be found of practical utility in the execution of this difficult branch ofjoinery.''— Builder. 
 " Almost every difficult phase of this somewhat intricate branch ofjoinery is elucidated by 
 the aid of plates and explanatory letterpress."— Furniture Gazette. 
 
 CIRCULAR WORK IN CARPENTRY AND JOINERY. 
 
 A Practical Treatise on Circular Work of Single and Double Curvature. By 
 George Collings. With Diagrams. Second Edition, i2mo, cloth . 2/6 
 
 “ An excellent example of what a book of this kind should be. Cheap in price, clear in 
 definition, and practical in the examples selected. "—Builder. 
 
CARPENTRY , TIMBER , 6-c. 
 
 29 
 
 HANDRAILING COMPLETE IN EIGHT LESSONS. 
 
 On the Square-Cut System. By J. S. Goldthorp, Head of Building 
 Department, Halifax Technical School. With Eight Plates and over 150 
 
 Practical Exercises. 4to, cloth. 3/6 
 
 “ Likely to be of considerable value to joiners and others who take a pride in good work. 
 The arrangement of the book is excellent. We heartily commend it to teachers and students.”— 
 Timber Trades Journal. 
 
 TIMBER MERCHANT’S and BUILDER’S COMPANION. 
 
 Containing New and Copious Tables of the Reduced Weight and Measure¬ 
 ment of Deals and Battens, of all sizes, from One to a Thousand Pieces, and 
 the relative Price that each size bears per Lineal Foot to any given Price per 
 Petersburgh Standard Hundred ; the Price per Cube Foot of Square Timber 
 to any given Price per Load of 50 Feet, &c., &c. By William Dowsing. 
 Fourth Edition, Revised and Corrected. Crown 8vo, cloth . . . 3/0 
 
 “We are glad to see a fourth edition of these admirable tables, which for correctness and 
 simplicity of arrangement leave nothing to be desired.” —Timber Trades Journal. 
 
 THE PRACTICAL TIMBER MERCHANT. 
 
 A Guide for the Use of Building Contractors, Surveyors, Builders, &c., 
 comprising useful Tables for all purposes connected with the Timber Trade, 
 Marks of Wood, Essay on the Strength of Timber, Remarks on the Growth of 
 Timber, &c. By W. Richardson. Second Edition. Fcap. 8vo, cloth . 3/6 
 “ This handy manual contains much valuable information for the use of timber merchants, 
 builders, foresters, and all others connected with the growth, sale, and manufacture of timber.”— 
 Journal 0/Forestry. 
 
 PACKING=CASE TABLES. 
 
 Showing the number of Superficial Feet in Boxes or Packing-Cases, from six 
 inches square and upwards. By W. Richardson, Timber Broker. Third 
 Edition. Oblong 4to, cloth . . 3/6 
 
 “ Invaluable labour-saving tables.”— Ironmonger. 
 
 GUIDE TO SUPERFICIAL MEASUREMENT. 
 
 Tables calculated from 1 to 200 inches in length by 1 to 108 inches in breadth. 
 For the use of Architects, Surveyors, Engineers, Timber Merchants, 
 Builders, &c. By James Hawkings. Fourth Edition. Fcap., cloth . 3/6 
 “ A useful collection of tables to facilitate rapid calculation of surfaces. The exact area of 
 any surface of which the limits have been ascertained can be instantly determined. The book will 
 be found of the greatest utility to all engaged in building operations.”— Scotsman. 
 
 PRACTICAL FORESTRY. 
 
 Its Bearing on the Improvement of Estates. By Charles E. Curtis, F.S.I., 
 F.S.S. Second Edition, Revised. Crown 8vo, cloth. [Just Published. 3/6 
 
 THE ELEMENTS OF FORESTRY. 
 
 Designed to afford Information concerning the Planting and Care of Forest 
 Trees for Ornament or Profit, with suggestions upon the Creation and Care of 
 Woodlands. By F. B. Hough. Large crown 8vo, cloth . 10/0 
 
 THE TIMBER IMPORTER’S, TIMBER MERCHANT’S, 
 
 AND BUILDER’S STANDARD GUIDE* 
 
 By Richard E. Grandy. Comprising :—An Analysis of Deal Standards, 
 Home and Foreign, with Comparative Values and Tabular Arrangements for 
 fixing Net Landed Cost on Baltic and North American Deals, including all 
 intermediate Expenses, freight, Insurance, &c.; together with copious Informa¬ 
 tion for the Retailer and Builder. Third Edition. i2mo, cloth . . 2/0 
 
 “Everything it pretends to be: built up gradually, it leads one from a forest to a treenail, 
 and throws in as a makeweight a host of material concerning bricks, columns, cisterns, &c.”— 
 English Mechanic. 
 
30 
 
 CROSBY LOCKWOOD & SON'S CATALOGUE. 
 
 DECORATIVE ARTS, &c. 
 
 SCHOOL OF PAINTING FOR THE IMITATION OF 
 
 WOODS AND MARBLES. 
 
 As Taught and Practised by A. R. Van der Burg and P. Van der Burg, 
 Directors of the Rotterdam Painting Institution. Royal folio, i8£ by 12^ in., 
 Illustrated with 24 full-size Coloured Plates ; also 12 plain Plates, comprising 
 154 Figures. Second and Cheaper Edition . . £1 11s. 6d. 
 
 List of Plates 1. Various Tools Required for wood Painting.—2,3. Walnut ; 
 Preliminary Stages of Graining and Finished Specimen.—4. Tools Used for 
 Marble Painting and Method of Manipulation.—5, 6. St. Remi Marble; 
 Earlier Operations and Finished Specimen. — 7. Methods of Sketching 
 Different Grains, Knots, &c.—8. 9. Ash: Preliminary Stages and Finished 
 Specimen.—10. Methods of Sketching Marble Grains.—ii, 12. Breche Marble; 
 PRELIMINARY STAGES OF WORKING AND FINISHED SPECIMEN.— 13. MAPLE ; METHODS 
 of Producing the Different Grains.—14. 15. Bird's-Eye Maple; Preliminary 
 Stages and Finished Specimen.—16. Methods of Sketching the Different 
 Species of white Marble.—17, 18. White Marble ; Preliminary Stages of 
 Process and Finished Specimen.—19. Mahogany; Specimens of Various Grains 
 and methods of Manipulation.—20, 21. Mahogany; F.arlier Stages and 
 Finished Specimen.—22, 23, 24. Sienna Marble; Varieties of Grain, Preliminary 
 Stages and Finished Specimen.—25, 26, 27. Juniper Wood; Methods of Pro¬ 
 ducing Grain, &c. ; preliminary Stages and Finished Specimen.—28, 29, 30. Vert 
 de mer Marble; Varieties of Grain and Methods of Working, Unfinished 
 and Finished Specimens.—31, 32, 33. Oak ; Varieties of Grain, Tools Employed 
 and Methods of manipulation, preliminary Stages and Finished Specimen.— 
 34, 35, 36. WAULSORT MARBLE; VARIETIES OF GRAIN, UNFINISHED AND FINISHED 
 SPECIMENS. 
 
 “ Those who desire to attain skill in the art of painting woods and marbles will find advantage 
 in consulting this book. . . . Some of the Working Men's Clubs should give their young men 
 the opportunity to study it ''--Builder. 
 
 “A comprehensive guide to the art. The explanations of the processes, the manipulation 
 and management of the colours, and the beautifully executed plates will not be the least valuable to 
 the student who aims at making his work a faithful transcript of nature.”— Building News. 
 
 " Students ai\d novices are fortunate who are able to become the possessors of so noble a 
 work. ”— The Architect 
 
 ELEMENTARY DECORATION. 
 
 A Guide to the Simpler Forms of Everyday Art. Together with PRACTICAL 
 HOUSE DECORATION. By James W. Facey. With numerous Illus¬ 
 trations. In One Vol., strongly half-bound .... . 5/0 
 
 HOUSE PAINTING, GRAINING, MARBLING, and SIGN 
 
 WRITING. 
 
 A Practical Manual of. By Ellis A. Davidson. Seventh Edition. With 
 Coloured Plates and Wood Engravings. i2mo, cloth boards . . . 6/0 
 
 “ A mass of information of use to the amateur and of value to the practical man ."—English 
 Mechanic . 
 
 THE DECORATOR’S ASSISTANT. 
 
 A Modern Guide for Decorative Artists and Amateurs, Painters, Writers, 
 Gilders, &c. Containing upwards of 600 Receipts, Rules, and Instructions ; 
 with a variety of Information for General Work connected with every Class of 
 Interior and Exterior Decorations, &c. Sixth Edition. 152 pp., cr. 8vo . 1/0 
 “ Full of receipts of value to decorators, painters, gilders, &c. The book contains the gist of 
 larger treatises on colour and technical processes. It would be difficult to meet with a work so full 
 ■ of varied information on the painter's art." —Building News . 
 
 MARBLE DECORATION 
 
 And the Terminology of British and Foreign Marbles. A Handbook for 
 Students. By George H. Blagrove, Author of “ Shoring and its Applica¬ 
 tion,” &c. With 28 Illustrations. Crown 8vo, cloth . . 3/6 
 
 "This most useful and much wanted handbook should be in the hands of every architect and 
 builder ."—Building World . 
 
 “ A carefully and usefully written treatise ; the work is essentially practical. '—Scotsman. 
 
DECORATIVE ARTS, &c. 
 
 3 i 
 
 DELAMOTTE’S WORKS ON ALPHABETS AND 
 ILLUMINATION. 
 
 ORNAMENTAL ALPHABETS, ANCIENT & MEDIEVAL. 
 
 From the Eighth Century, with Numerals; including Gothic, Church-Text,, 
 large and small, German, Italian, Arabesque, Initials for Illumination,. 
 Monograms, Crosses, See., &c., for the use of Architectural and Engineering. 
 Draughtsmen, Missal Painters, Masons, Decorative Painters, Lithographers,, 
 Engravers, Carvers, &c., & c. Collected and Engraved by F. Delamotte, and! 
 printed in Colours. New and Cheaper Edition. Royal 8vo, oblong,. 
 
 ornamental boards .. 2/6 
 
 “ For those who insert enamelled sentences round gilded chalices, who blazon shop legends; 
 over shop-doors, who letter church walls with pithy sentences from the Decalogue, this book will be. 
 useful ."—A thenezum. 
 
 MODERN ALPHABETS, PLAIN AND ORNAMENTAL- 
 
 Including German, Old English, Saxon, Italic, Perspective. Greek, Hebrew,, 
 Court Hand, Engrossing, Tuscan, Riband, Gothic, Rustic, and Arabesque ;; 
 with several Original Designs, and an Analysis of the Roman and Old English 
 Alphabets, large and small, and Numerals, for the use of Draughtsmen* 
 Surveyors, Masons, Decorative Painters, Lithographers, Engravers, Carvers-, 
 &c. Collected and Engraved by F. Delamotte, and printed in Colours. 
 New and Cheaper Edition. Royal 8vo, oblong, ornamental boards . 2/6 
 
 “ There is comprised in it every possible shape into which the letters of the alphabet and 
 numerals can be formed, and the talent which has been expended in the conception of the various 
 plain and ornamental letters is wonderful.”— Standard. 
 
 MEDIAEVAL ALPHABETS AND INITIALS FOR 
 
 ILLUMINATORS. 
 
 By F. G. Delamotte. Containing 21 Plates and Illuminated Title, printed 
 in Gold and Colours. With an Introduction by J. Willis Brooks. Fourth 
 and Cheaper Edition. Small 4to, ornamental boards .... 4/0 
 
 “ A volume in which the letters of the alphabet come forth glorified in gilding and all the 
 colours of the prism interwoven and intertwined and intermingled.”— Sun. 
 
 A PRIMER OF THE ART OF ILLUMINATION. 
 
 For the Use of Beginners ; with a Rudimentary Treatise on the Art, Practical 
 Directions for its Exercise, and Examples taken from Illuminated MSS., 
 printed in Gold and Colours. By F. Delamotte. New and Cheaper 
 Edition. Small 4to, ornamental boards ....... 6/0 
 
 “ The examples of ancient MSS. recommended to the student, which, with much good sense, 
 the author chooses from collections accessible to all, are selected with judgment and knowledge as 
 well as tast z."— A.thcnceum. 
 
 THE EMBROIDERER’S BOOK OF DESIGN. 
 
 Containing Initials, Emblems, Cyphers, Monograms, Ornamental Borders, 
 Ecclesiastical Devices, Mediaeval and Modern Alphabets, and National 
 Emblems. Collected by F. Delamotte, and printed in Colours. Oblong 
 
 royal 8vo, ornamental wrapper . . . . . . . . . 1/6 
 
 “The book will be of great assistance to ladies and young children who are endowed with 
 the art of plying the needle in this most ornamental and useful pretty work ."—East Anglia n Times. 
 
 INSTRUCTIONS IN WOOD-CARVING FOR AMATEURS. 
 
 With Hints on Design. By A Lady. With 10 Plates. New and Cheaper 
 Edition. Crown 8vo, in emblematic wrapper ...... 2/0 
 
 “ The handicraft of the wood-carver, so well as a book can impart it, may be learnt from * A 
 Lady's ’ publication.”— Athenceum. 
 
 PAINTING POPULARLY EXPLAINED. 
 
 By Thomas John Gullick, Painter, and John Times, F.S.A. Including 
 Fresco, Oil, Mosaic, Water-Colour, Water-Glass, Tempera, Encaustic, 
 Miniature, Painting on Ivory, Vellum, Pottery, Enamel, Glass, &c. Fifth 
 Edition. Crown 8vo, cloth. 5/0 
 
 *** Adopted as a Prize Book at South Kensington. 
 
 “ Much may be learned, even by those who fancy they do not require to be taught, from the. 
 careful perusal of this unpretending but comprehensive treatise ."—Art Journal. 
 
32 
 
 CROSBY LOCKWOOD & SON'S CATALOGUE. 
 
 NATURAL SCIENCE, &c. 
 
 THE VISIBLE UNIVERSE. 
 
 Chapters on the Origin and Construction of the Heavens. By J. E. Gore 
 F.R.A.S., Author of “ Star Groups,”&c. Illustrated by 6 Stellar Photographs 
 and 12 Plates. Demy 8vo, cloth.. . . 1 6/0 
 
 " A valuable and lucid summary of recent astronomical theory, rendered more valuable and 
 attractive by a series of stellar photographs and other illustrations.”— The Times. 
 
 “ In presenting a clear and concise account of the present state of our knowledge Mr. Gore 
 has made a valuable addition to the literature of the subject.”— Nature. 
 
 44 Mr. Gore's ' Visible Universe’ is one of the finest works on astronomical science that have 
 recently appeared in our language. In spirit and in method it is scientific from cover to cover, but 
 the style is so clear and attractive that it will be as acceptable and as readable to those who make 
 no scientific pretensions as to those who devote themselves specially to matters astronomical."— 
 Leeds Mercury. 
 
 STAR GROUPS. 
 
 A Student’s Guide to the Constellations. By J. Ellard Gore, F.R.A.S. 
 M.R.I.A., &c., Author of “The Visible Universe,” “The Scenery of the 
 Heavens,” &c. With 30 Maps. Small 4to, cloth ..... 6/0 
 
 “ The volume contains thirty maps showing stars of the sixth magnitude—the usual naked-eye 
 limit— and each is accompanied by a brief commentary adapted to facilitate recognition and bring 
 to notice objects of special interest. For the purpose of a preliminary survey of the 4 midnight 
 pomp ’ of the heavens nothing could be better than a set of delineations averaging scarcely twenty 
 square inches in area and including nothing that cannot at once be identified.”— Saturday Review 
 
 AN ASTRONOMICAL GLOSSARY. 
 
 Or, Dictionary of Terms used in Astronomy. With Tables of Data and Lists 
 of Remarkable and Interesting Celestial Objects. By J. Ellard Gore, 
 F.R.A.S., Author of “ The Visible Universe,” &c. Small crown 8vo, cloth. 
 
 2/6 
 
 “A very useful little work for beginners in astronomy, and not to be despised by more 
 advanced students.”— The Times. 
 
 “ A very handy book . . . the utility of which is much increased by its valuable tables of 
 astronomical data.”— Athenaeum. 
 
 THE MICROSCOPE. 
 
 Its Construction and Management. Including Technique, Photo-micrography, 
 and the Past and Future of the Microscope. By Dr. Henri van Heurck. 
 Re-Edited and Augmented from the Fourth French Edition, and Translated 
 by Wynne E. Baxter, F.G.S. 400 pp., with upwards of 250 Woodcuts, 
 imp. 8vo, cloth ........... 1 S O 
 
 “ A translation of a well-known work, at once popular and comprehensive.”— Times. 
 
 44 The translation is as felicitous as it is accurate.”— Nature. 
 
 PHOTOMICROGRAPHY. 
 
 By Dr. H. van Heurck. Extracted from the above Work. Royal 8vo, with 
 Illustrations, sewed. 1/0 
 
 ASTRONOMY* 
 
 By the late Rev. Robert Main, M.A., F.R.S. Third Edition, Revised by 
 William Thynne Lynn, B.A., F.R.A.S., formerly of the Royal Observatory, 
 Greenwich. i2mo, cloth .......... 2/0 
 
 “A sound and simple treatise, very carefully edited, and a capital book for beginners."— 
 Knowledge. 
 
 44 Accurately brought down to the requirements of the present time by Mr. Lynn.”— 
 Educational Times. 
 
 A MANUAL OF THE MOLLUSCA. 
 
 A Treatise on Recent and Fossil Shells. By S. P. Woodward, A.L.S., 
 F.G.S. With an Appendix on Recent and Fossil Conchological 
 Discoveries, by Ralph Tate, A.L.S., F.G.S. With 23 Plates and 
 upwards of 300 Woodcuts. Reprint of Fourth Edition (1880). Crown 8vo, 
 cloth .. • 7/6 
 
 44 A most valuable storehouse of conchological and geological information. ’— Science Gossip. 
 
 THE TWIN RECORDS OF CREATION. 
 
 Or, Geology and Genesis, their Perfect Harmony and Wonderful Concord. 
 By G. W. V. le Vaux. 8vo, cloth ...... SI O 
 
 44 A valuable contribution to the evidences of Revelation, and disposes very conclusively of 
 the arguments of those who would set God’s Works against God's Word No real difficulty is 
 shirked, and no sophistry is left unexposed. "—The Rock. 
 
NATURAL SCIENCE, &c. 
 
 33 
 
 HANDBOOK OF MECHANICS. 
 
 By Dr. Lardner. Enlarged and re-written by Benjamin Loewy, F.R.A.S. 
 
 378 Illustrations. Post 8vo, cloth. 6/0 
 
 “ The perspicuity of the original has been retained, and chapters which had become obsolete 
 have been replaced by others of more modern character. The explanations throughout are 
 studiously popular, and care has been taken to show the application of the various branches of 
 physics to the industrial arts, and to the practical business of life.”— Mining Journal. 
 
 HANDBOOK OF HYDROSTATICS AND PNEUMATICS. 
 
 By Dr. Lardner. New Edition, Revised and Enlarged by Benjamin Loewy, 
 F.R.A.S. With 236 Illustrations. Post 8vo, cloth. . . . . 5/0 
 
 “For those ‘who desire to attain an accurate knowledge of physical science without the 
 profound methods of mathematical investigation,’ this work is well adapted.”— Chemical News. 
 
 HANDBOOK OF HEAT. 
 
 By Dr. Lardner. Edited and re-written by Benjamin Loewy, F.R.A.S., &c. 
 
 117 Illustrations. Post 8vo, cloth.. 0/0 
 
 “The style is always clear and precise, and conveys instruction without leaving any cloudiness 
 or lurking doubts behind.”— Engineering. 
 
 HANDBOOK OF OPTICS. 
 
 By Dr. Lardner. New Edition. Edited by T. Olver Harding, B.A. Lond. 
 With 298 Illustrations. Small 8vo, 448 pp., cloth ..... 5/0 
 
 “ Written by one of the ablest English scientific writers, beautifully and elaborately illustrated.” 
 — Mechanics' Magazine. 
 
 ELECTRICITY, MAGNETISM, AND ACOUSTICS. 
 
 By Dr. Lardner. Edited by Geo. Carey Foster, B.A., F.C.S. With 
 400 Illustrations. Small 8vo, cloth ..... ... 5/0 
 
 “The book could not have been entrusted to any one better calculated to preserve the terse 
 and lucid style of Lardner, while correcting his errors and bringing up his work to the present 
 state of scientific knowledge."— Popular Science Review. 
 
 HANDBOOK OF ASTRONOMY. 
 
 By Dr. Lardner. Fourth Edition. Revised and Edited by Edwin Dunkin, 
 F.R.A.S., Royal Observatory, Greenwich. With 38 Plates and upwards of 
 100 Woodcuts. 8vo, cloth ......... 0/0 
 
 “Probably no other book contains the same amount of information in so compendious and 
 well arranged a form—certainly none at the price at which this is offered to the public.”— Athcnceum. 
 
 “ We can do no other than pronounce this work a most valuable manual of astronomy, and 
 we strongly recommend it to all who wish to acquire a general—but at the same time correct— 
 acquaintance with this sublime science.”— Quarterly Journal ojScience. 
 
 MUSEUM OF SCIENCE AND ART. 
 
 Edited by Dr. Lardner. With upwards of 1.200 Engravings on Wood. In 
 Six Double Volumes, £1 Is. in a new and elegant cloth binding ; or hand¬ 
 somely bound in half-morocco ...... £1 11s. 60. 
 
 “ A cheap and interesting publication, alike informing and attractive. The papers combine 
 subjects of importance and great scientific knowledge, considerable inductive powers, and a popular 
 style of treatment,"— Spectator. 
 
 Separate books formed from the above. 
 
 Common Things Explained. 
 The Microscope. 2 s. cloth. 
 Popular Geology. 2 s. 6 d. cloth 
 Popular Physics. 2 s. 6 d. cloth. 
 
 55 - 
 
 Steam and its Uses. 2s. cloth. 
 Popular Astronomy. 4s. 6 d. cloth. 
 The Bee and White Ants. 2s. cloth. 
 The Electric Telegraph, is. 6 ci. 
 
 NATURAL PHILOSOPHY FOR SCHOOLS. 
 
 By Dr. Lardner. Fcap. 8vo. 3/0 
 
 “ A very convenient class book for junior students in private schools.”— British Quarterly 
 Review. 
 
 ANIMAL PHYSIOLOGY FOR SCHOOLS. 
 
 By Dr. Lardner. Fcap. 8vo. 3/0 
 
 “ Clearly written, well arranged, and excellently illustrated.”— Gardener's Chronicle. 
 
 THE ELECTRIC TELEGRAPH. 
 
 By Dr. Lardner. Revised by E. B. Bright, F.R.A.S. Fcap. 8vo. 2/0 
 “One of the most readable books extant on the Electric T elegraph.”— English Mechanic. 
 
 L C 
 
34 CROSBY LOCKWOOD &■ SON'S CATALOGUE. 
 
 CHEMICAL MANUFACTURES, 
 CHEMISTRY, &c. 
 
 WATER AND ITS PURIFICATION. 
 
 A Handbook for the Use of Local Authorities, Sanitary Officers, and others 
 interested in Water Supply. By S. Rideal, D.Sc. Lond., F.I.C. With 
 numerous Illustrations and Tables. Crown 8vo, cloth. [ Just Published. 7 IS 
 “ Dr. Rideal's book is both interesting - and accurate, and contains a most useful resume of 
 the latest knowledge upon the subject of which it treats. It ought to be of great service to all who 
 are connected with the supply of water for domestic or manufacturing purposes.” —The Engineer. 
 
 “ Dealing as clearly as it does with the various ramifications of such an important subject as 
 water and its purification it may be warmly recommended. Local authorities and all engaged in 
 sanitary affairs, and others interested in water supply, will read its pages with profit ”— Lancet. 
 
 ENGINEERING CHEMISTRY. 
 
 A Practical Treatise for the Use of Analytical Chemists, Engineers, Iron 
 Masters, Iron Founders, Students and others. Comprising Methods of Analysis 
 and Valuation of the Principal Materials used in Engineering Work, with 
 numerous Analyses, Examples and Suggestions. By H. J. Phillips, F.I.C., 
 F.C.S. Second Edition, Enlarged. Crown 8vo, 400 pp., with Illustrations, 
 
 cloth.1 0 IS 
 
 “In this work the author has rendered no small service to a numerous body of practical 
 men. . . . The analytical methods may be pronounced most satisfactory, being as accurate as the 
 despatch required of engineering chemists permits.”— Chemical News. 
 
 “A handy and concise resume of approved methods of analysing and valuing metals, oils, 
 fuels, &c. It is, in fact, a work for chemists, a guide to the routine of the engineeringlaboratory. . . . 
 The book is full of good things. As a handbook of technical analysis, it is very welcome."— Builder. 
 
 “The analytical methods given are, as a whole, such as are likely to give rapid and trust¬ 
 worthy results in experienced hands. . . . There is much excellent descriptive matter in the work, 
 the chapter on ‘Oils and Lubrication’ being specially'noticeable in this respect.”— Engineer. 
 
 NITRO=EXPLOSIVES. 
 
 A Practical Treatise concerning the Properties, Manufacture, and Analysis 
 of Nitrated Substances, including the Fulminates, Smokeless Powders, and 
 Celluloid. By P. G. .Sanford, F.I.C., Consulting Chemist to the Cotton Powder 
 Company, &c. With Illustrations. Crown 8vo, cloth. [ Just Published. O/Q 
 “ Any one having the requisite apparatus and materials could make nitro-glycerine or gun¬ 
 cotton, to say nothing of other explosives, by the aid of the instructions contained in this volume. 
 This is one of the very few text-books in which can be found just what is wanted. Mr. Sanford 
 goes steadily through the whole list of explosives commonly used, he names any given explosive, 
 and tells us of what it is composed and how it is manufactured. The book is excellent throughout.” 
 — The Engineer. 
 
 “ A thoroughly practical account of the manufacture, properties, &c., of nitro-explosives It 
 is an admirable work, which reflects the highest credit on the author." —Colliery Guardian. 
 
 A HANDBOOK ON MODERN EXPLOSIVES. 
 
 A Practical Treatise on the Manufacture and Use of Dynamite, Gun-Cotton, 
 Nitro-Glycerine and other Explosive Compounds, including Collodion-Cotton. 
 With Chapters on Explosives in Practical Application. By M. Eissler, 
 Mining Engineer, and Metallurgical Chemist. Second Edition, Enlarged. 
 With 150 Illustrations. Crown 8vo, cloth. [Just Published. J 2/6 
 
 “ Useful not only to the miner, but also to officers of both services to whom blasting and the 
 use of explosives generally may at any time become a necessary auxiliary.” — Nature. 
 
 “ A veritable mine of information on the subject of explosives employed for military, mining, 
 and blasting purposes.”— slr?7iy and Navy Gazette. 
 
 DANGEROUS GOODS. 
 
 Their Sources and Properties, Modes of Storage and Transport. With Notes 
 and Comments on Accidents arising therefrom, together with the Government 
 and Railway Classifications, Acts of Parliament, &c. A Guide for the Use of 
 Government and Railway Officials, Steamship Owners, Insurance Companies 
 and Manufacturers, and Users of Explosives and Dangerous Goods. By 
 H. Joshua Phillips, F.I.C., F.C.S. Crown 8vo, 374 pp., cloth . . 9/0 
 
 “We can with justice compliment the author upon the very satisfactory work he has 
 produced, and can recommend it with confidence to all who have to handle, store, or ship any of the 
 very large c!a;s of materials comprised in the heading of dangerous goods."— Mining Journal 
 “Meiits a wide circulation, and an intelligent, appreciative study."— Chemical News. 
 
CHEMICAL MANUFACTURES, CHEMISTRY, &-c. 35 
 
 A MANUAL OF THE ALKALI TRADE. 
 
 Including the Manufacture of Sulphuric Acid, Sulphate of Soda, and Bleaching 
 Powder. By John Lomas, Alkali Manufacturer, Newcastle-upon-Tyne and 
 London. 390 pp. of Text. With 232 Illustrations and Working Drawings. 
 Second Edition, with Additions. Super-royal 8vo, cloth . . £1 Os. 
 
 “ This book is written by a manufacturer for manufacturers. The working details of the most 
 approved forms of .apparatus are given, and these are accompanied by no less than 232 wood 
 engravings, all of which may be used for the purposes of construction. Every step in the manu¬ 
 facture is very fully described in this manual, and each improvement explained.”— Athenceum. 
 
 “ We find not merely a sound and luminous explanation of the chemical principles of the 
 trade, but a notice of numerous matters which have a most important bearing on the successful 
 conduct of alkali works, but which are generally overlooked by even experienced technological 
 authors.”— Chemical Rernew. 
 
 THE BLOWPIPE in CHEMISTRY, MINERALOGY, and 
 
 GEOLOGY. 
 
 Containing all known Methods of Anhydrous Analysis, many Working 
 Examples, and Instructions for Making Apparatus. By Lieut.-Colonel W. A. 
 Ross, R.A., F.G.S. With 120 Illustrations. Second Edition, Enlarged. 
 
 Crown 8vo, cloth. BIO 
 
 “ The student who goes conscientiously through the course of experimentation here laid down 
 will gain a better insight into inorganic chemistry and mineralogy than if he had ‘got up’ any of the 
 best text-books of the day, and passed any number of examinations in their contents."— Chemical 
 News. 
 
 COMMERCIAL HANDBOOK OF CHEMICAL ANALYSIS. 
 
 Or, Practical Instructions for the Determination of the Intrinsic or Commercial 
 Value of Substances used in Manufactures, in Trades, and in the Arts. By 
 A. Normandy. New Edition by H. M. Noad, Ph.D., F.R.S. Crown 8vo, 
 
 cloth.. . . . 12/6 
 
 “ We strongly recommend this book to our readers as a guide, alike indispensable to the 
 housewife as to the pharmaceutical practitioner.”— Medical Times. 
 
 THE MANUAL OF COLOURS AND DYE=WARES. 
 
 Their Properties, Applications, Valuations, Impurities and Sophistications. 
 
 For the Use of Dyers, Printers, Drysalters, Brokers, &c. By J. W. Slater. 
 
 Second Edition, Revised and greatly Enlarged. Crown 8vo, cloth . 7/6 
 
 “ A complete encyclopaedia of the materia tinctoria. The information given respecting each 
 article is full and precise, and the methods of determining the value of articles such as these, so 
 liable to sophistication, are given with clearness, and are practical as well as valuable.”— Chemist 
 and Druggist. 
 
 “There is no other work which covers precisely the same ground. To students preparing 
 for examinations in dyeing and printing it will prove exceedingly useful."— Chemical News. 
 
 A HANDY BOOK FOR BREWERS. 
 
 Being a Practical Guide to the Art of Brewing and Malting. Embracing the 
 Conclusions of Modern Research which bear upon the Practice of Brewing. 
 By Herbert Edwards Wright, M.A. Second Edition, Enlarged. Crown 
 8vo, 530 pp., cloth. [Just Published. 12/6 
 
 “ May be consulted with advantage by the student who is preparing himself for examinational 
 tests, while the scientific brewer will find in it a rffsumJ of all the most important discoveries of 
 modern times. The work is written throughout in a clear and concise manner, and the author 
 takes great care to discriminate between vague theories and well-established facts."— Brewers' 
 Journal. 
 
 “ We have great pleasure in recommending this handy book, and have no hesitation in saying 
 that it is one of the best—if not the best—which has yet been written on the subject of beer-brewing 
 in this country ; it should have a place on the shelves of every brewer’s library.”— Brewer s 
 Guardian. 
 
 “ Although the requirements of the student are primarily considered, an acquaintance of half- 
 an-hour's duration cannot fail to impress the practical brewer with the sense of having found a 
 trustworthy guide and practical counsellor in brewery matters."— Chemical Trade Journal. 
 
 FUELS: SOLID, LIQUID, AND GASEOUS. 
 
 Their Analysis and Valuation. For the Use of Chemists and Engineers. By 
 H. J. Phillips, F.C.S., formerly Analytical and Consulting Chemist to the 
 G.E. Rlwy. Third Edition, Revised and Enlarged. Crown 8vo, cloth 2/0 
 “ Ought to have its place in the laboratory of every metallurgical establishment and wherever 
 fuel is used on a large scale."— Chemical News . 
 
 C 2 
 
36 CROSBY LOCKWOOD & SON'S CATALOGUE . 
 
 THE ARTISTS’ MANUAL OF PIGMENTS. 
 
 Showing their Composition, Conditions of Permanency, Non-Permanency, and 
 Adulterations; Effects in Combination with Each Other and with Vehicles ; 
 and the most Reliable Tests of Purity. By H. C. Standage. Third Edition, 
 
 crown 8vo, cloth. 2/6 
 
 “ This work is indeed multum-in-parvo , and we can, with good conscience, recommend it to 
 all who come in contact with pigments, whether as makers, dealers, or users ."—Chemical Review. 
 
 A POCKET=BOOK OF MENSURATION AND GAUGING. 
 
 Containing ‘Tables, Rules, and Memoranda for Revenue Officers, Brewers, 
 Spirit Merchants, &c. By J. B. Mant, Inland Revenue. Second Edition, 
 Revised. i8mo, leather .......... 4/0 
 
 “This handy and useful book is adapted to the requirements of the Inland Revenue Depart¬ 
 ment, and will be a favourite book of reference. The range of subjects is comprehensive, and the 
 arrangement simple and clear.”— Civilian, 
 
 “Should be in the hands of every practical brewer."— Brewers' Journal. 
 
 INDUSTRIAL ARTS, TRADES AND 
 MANUFACTURES. 
 
 MODERN CYCLES. 
 
 A Practical Handbook on their Construction and Repair. By A. J. Wallis- 
 Tayler, A. M. Inst. C. E. Author of “ Refrigerating Machinery,” &c. With 
 upwards of 300 Illustrations. Crown 8vo, cloth. [Just Published. 10/6 
 
 “The large trade that is done in the component parts of bicycles has placed in the way of 
 men mechanically inclined extraordinary facilities for building bicycles for their own use. . . . The 
 book will prove a valuable guide for all those who aspire to the manufacture or repair of their own 
 machines."— The Field. 
 
 “ A most comprehensive and up-to-date treatise."— The Cycle. 
 
 “ A very useful book, which is quite entitled to rank as a standard work for students of cycle 
 construction. ’ Wheeling. 
 
 TEA PLANTING AND MANUFACTURE. 
 
 (A Text Book of.) Comprising Chapters on the History and Development of 
 the Industry, the Cultivation of the Plant, the Preparation of the Leaf for the 
 Market, the Botany and Chemistry of Tea, &c. With some Account of the 
 Laws affecting Labour in Tea Gardens in Assam and elsewhere. By David 
 Crole, late of the Jokai Tea Company, &c. With Plates and other Illustra¬ 
 tions. Medium 8vo, cloth. [Just Published. 16/0 
 
 " The author writes as an expert, and gives the result of his personal experiences. The work 
 can hardly fail to be of practical interest to tea growers and tea manufacturers."— British Trade 
 Journal. 
 
 COTTON MANUFACTURE. 
 
 A Manual of Practical Instruction of the Processes of Opening, Carding, 
 Combing, Drawing, Doubling and Spinning of Cotton, the Methods of 
 Dyeing, &c. For the Use of Operatives, Overlookers, and Manufacturers. 
 By John Lister, Technical Instructor, Pendleton. Svo, cloth . . *7/6 
 
 “This invaluable volume is a distinct advance in the literature of cotton manufacture.”— 
 Machinery. 
 
 “ It is thoroughly reliable, fulfilling nearly all the requirements desired. '— Glasgcnu Herald. 
 
 FLOUR MANUFACTURE. 
 
 A Treatise on Milling Science and Practice. By Friedrich Kick, Imperial 
 Regierungsrath, Professor of Mechanical Technology in the Imperial German 
 Polytechnic Institute, Prague. Translated from the Second Enlarged and 
 Revised Edition with Supplement. By H. H. P. Powles, Assoc. Memb. 
 Institution of Civil Engineers. Nearly 400 pp. Illustrated with 28 Folding 
 Plates, and 167 Woodcuts. Royal 8vo, cloth. £1 6 s. 
 
 “ This valuable work is, and will remain, the standard authority on the science of milling. . . . 
 The miller who has read and digested this work will have laid the foundation, so to speak, of a 
 successful career ; he will have acquired a number of general principles which he can proceed to 
 apply. In this handsome volume we at last have the accepted text-book of modem milling in good, 
 sound English, which has little, if any, trace of the German idiom.”— The Miller. 
 
 “ The appearance of this celebrated work in English is very opportune, and British millers 
 will, we are sure, not be slow in availing themselves of its pages."— Millers' Gazette. 
 
INDUSTRIAL AND USEFUL ARTS. 
 
 37 
 
 CEMENTS, PASTES, GLUES AND GUMS. 
 
 A Practical Guide to the Manufacture and Application of the various Aggluti- 
 nants required in the Building, Metal-Working, Wood-Working, and Leather- 
 Working Trades, and for Workshop, Laboratory or Office Use. With upwards 
 of 900 Recipes and Formulae. By H. C. Standage, Chemist. Third Edition. 
 Crown 8vo, cloth. [Just Published. 2/0 
 
 “We have pleasure in speaking favourably of this volume. So far as we have had 
 experience, which is not inconsiderable, this manual is trustworthy.” — Atheiuzinn. 
 
 “As a revelation of what are considered trade secrets, this book will arouse an amount of 
 curiosity among the large number of industries it touches.”— Daily Chronicle. 
 
 THE ART OF SOAP=MAKING. 
 
 A Practical Handbook of the Manufacture of Hard and Soft Soaps, Toilet 
 Soaps, See. Including many New Processes, and a Chapter on the Recovery of 
 Glycerine from Waste Leys. By Alx. Watt. Fifth Edition, Revised, with 
 an Appendix on Modern Candlemaking. Crown Svo, cloth . . . 7/6 
 
 “The work will prove very useful, not merely to the technological student, but to the 
 practical soap boiler who wishes to understand the theory of his art.”— Chemical News. 
 
 " A thoroughly practical treatise on an art which has almost no literature in our language. 
 We congratulate the author on the success of his endeavour to fill a void in English technical 
 literature."— Nature. 
 
 PRACTICAL PAPER=MAKING. 
 
 A Manual for Paper-Makers and Owners and Managers of Paper-Mills. With 
 Tables, Calculations, See. By G. Clapperton, Paper-Maker. With Illus¬ 
 trations of Fibres from Micro-Photographs. Crown 8vo, cloth . . S/0 
 
 “ The author caters for the requirements of responsible mill hands, apprentices, &c., whilst 
 his manual will be found of great service to students of technology, as well as to veteran paper- 
 makers and mill owners. The illustrations form an excellent feature."— The World's Paper Trade 
 Revierc. 
 
 “ We recommend everybody interested in the trade to get a copy of this thoroughly practical 
 book.”— Paper Making. 
 
 THE ART OF PAPER=MAKING. 
 
 A Practical Handbook of the Manufacture of Paper from Rags, Esparto, 
 Straw, and other Fibrous Materials. Including the Manufacture of Pulp from 
 Wood Fibre, with a Description of the Machinery and Appliances used. To 
 which are added Details of Processes for Recovering Soda from Waste Liquors. 
 By Alexander Watt, Author of “The Art of Soap-Making.” With Illus¬ 
 trations. Crown Svo, cloth . . . . . . . . 7 IS 
 
 “It may be regarded as the standard work on the subject. The book is full of valuable 
 information. The ‘Art of Paper-Making’ is in every respect a model of a text-book, either for a 
 technical class, or for the private student.” —Paper and Printing Trades Journal. 
 
 THE ART OF LEATHER MANUFACTURE. 
 
 Being a Practical Handbook, in which the Operations of Tanning, Currying, 
 and Leather Dressing are fully Described, and the Principles of Tanning 
 Explained, and many Recent Processes Introduced ; as also Methods for the 
 Estimation of Tannin, and a Description of the Arts of Glue Boiling, Gut 
 Dressing, See. By Alexander Watt, Author of “ Soap-Making,” See. 
 
 Fourth Edition. Crown Svo, cloth .. 9/0 
 
 “ A sound, comprehensive treatise on tanning and its accessories. The book is an eminently 
 valuable production, which redounds to the credit of both author and publishers.”— Chemical 
 Review. 
 
 THE ART OF BOOT AND SHOE MAKING. 
 
 A Practical Handbook, including Measurement, Last-Fitting, Cutting-Out, 
 Closing and Making, with a Description of the most approved Machinery 
 Employed. By John B. Leno, late Editor of St. Crispin , and The Boot and 
 Shoe-Maker. i2mo, cloth. 2/0 
 
 MECHANICAL DENTISTRY. 
 
 A Practical Treatise on the Construction of the various kinds of Artificial 
 Dentures. Comprising also Useful Formulae, Tables, and Receipts for Gold 
 Plate, Clasps, Solders, Sec., Sec. By C. Hunter. Third Edition. With 
 100 Wood Engravings. Crown Svo, cloth. 3/6 
 
38 CROSBY LOCKWOOD &■ SON'S CATALOGUE. 
 
 WOOD ENGRAVING. 
 
 A Practical and Easy Introduction to the Study of the Art. By W. N. Brown. 
 i2mo, cloth.g 
 
 "The book is clear and complete, and will be useful to any one wanting to understand the 
 first elements of the beautiful art of wood engraving.”— Graphic. 
 
 MODERN HOROLOGY, IN THEORY AND PRACTICE. 
 
 Translated from the French of Claudius Sauniek, ex-Director of the School 
 of Horology at Macon, by Julien Tripplin, F.R.A.S., Besancon Watch 
 Manufacturer, and Edward Rigg, M.A., Assayer in the Royal Mint. With 
 Seventy-eight Woodcuts and Twenty-two Coloured Copper Plates. Second 
 Edition. Super-royal 8vo, cloth, £2 2s. i half-calf . . . £2 1 Os. 
 
 " There is no horological work in the English language at all to be compared to this produc¬ 
 tion of M. Saunier’s for clearness and completeness. It is alike good as a guide for the student and 
 as a reference for the experienced horologist and skilled workman ."—Horological Journal. 
 
 “ The latest, the most complete, and the most reliable of those literary productions to which 
 continental watchmakers are indebted for the mechanical superiority over their English brethren 
 —in fact, the Book of Books, is M. Saunier s ‘ Treatise.’ ”— IVatchmaker, Jeweller , and Silversmith. 
 
 THE WATCH ADJUSTER’S MANUAL. 
 
 A Practical Guide for the Watch and Chronometer Adjuster in Making, 
 Springing, Timing and Adjusting for Isochronism, Positions and Temperatures. 
 By C. E. Fritts. 370 pp., with Illustrations, 8vo, cloth . . . 16 0 
 
 THE WATCHMAKER’S HANDBOOK. 
 
 Intended as a Workshop Companion for those engaged in Watchmaking and 
 the Allied Mechanical Arts. Translated from the French of Claudius 
 Saunier, and enlarged by Julien Tripplin, F.R.A.S., and Edward 
 Rigg, M.A., Assayer in the Royal Mint. Third Edition. 8vo, cloth. 9 0 
 
 “ Each part is truly a treatise in itself. The arrangement is good and the language is clear 
 and concise. It is an admirable guide for the young watchmaker."— Engineering. 
 
 "It is impossible to speak too highly of its excellence. It fulfils every requirement in a 
 handbook intended for the use of a workman. Should be found in every workshop .”—Watch and 
 Clockmaker. 
 
 A HISTORY OF WATCHES & OTHER TIMEKEEPERS. 
 
 By James F. Kendal, M.B.H. Inst. Boards, 1/6; or cloth, gilt . 2/6 
 
 " The best which has yet appeared on this subject in the English language.”— Industries. 
 "Open the book where you may, there is interesting matter in it concerning the ingenious 
 devices of the ancient or modern horologer ."—Saturday Review. 
 
 ELECTRO=DEPOSITION. 
 
 A Practical Treatise on the Electrolysis of Gold, Silver, Copper, Nickel, and 
 other Metals and Alloys. With Descriptions of Voltaic Batteries, Magneto 
 and Dynamo-Electric Machines, Thermopiles, and of the /Materials and 
 Processes used in every Department of the Art, and several Chapters on 
 Electro-Metallurgy. By Alexander Watt, Author of “ Electro- 
 Metallurgy, ” &c. Third Edition, Revised. Crown 8vo, cloth . 9/0 
 
 “Eminently a book for the practical worker in electro-deposition. It contains practical 
 descriptions of methods, processes and materials, as actually pursued and used in the workshop."— 
 Engi)ieer. 
 
 ELECTRO=METALLURGY. 
 
 Practically Treated. By Alexander Watt. Tenth Edition, including the 
 most recent Processes. i2mo, cloth . . . . . . -3/6 
 
 " From this book both amateur and artisan may learn everything necessary for the successful 
 prosecution of electroplating."— Iron. 
 
 JEWELLER’S ASSISTANT IN WORKING IN GOLD. 
 
 A Practical Treatise for Masters and Workmen, Compiled from the Experience 
 of Thirty Years’Workshop Practice. By George E. Gee, Author of “The 
 
 Goldsmith’s Handbook,” &c. Crown 8vo, cloth. 7/6 
 
 " This manual of technical education is apparently destined to be a valuable auxiliary to a 
 handicraft which is certainly capable of great improvement ."—The Times. 
 
INDUSTRIAL AND USEFUL ARTS. 
 
 39 
 
 ELECTROPLATING. 
 
 A Practical Handbook on the Deposition of Copper, Silver, Nickel, Gold, 
 Aluminium, Brass, Platinum, &c., &c. By J. W. Urquhart, C.E. Third 
 
 Edition, Revised. Crown 8vo, cloth.5/0 
 
 “ An excellent practical manual."— Engineering. 
 
 “ An excellent work, giving the newest information."— Horo’.ogical Journal. 
 
 ELECTROTYPING. 
 
 The Reproduction and Multiplication of Printing Surfaces and Works of Art 
 by the Electro-Deposition of Metals. By J. W. Urquhart, C.E. Crown 8vo, 
 
 cloth. 5/0 
 
 “ The book is thoroughly practical; the reader is, therefore, conducted through the leading 
 laws of electricity, then through the metals used by electrotypers, the apparatus, and the depositing 
 processes, up to the final preparation of the work."— Art Journal. 
 
 GOLDSMITH’S HANDBOOK. 
 
 By George E. Gee, Jeweller, &c. Fourth Edition. i2mo, cloth. . 3/6 
 “A good, sound educator, and will be generally accepted as an authority."— Horological 
 Journal. 
 
 SILVERSMITH’S HANDBOOK. 
 
 By George E. Gee, Jeweller, &c. Third Edition, with numerous Illustra¬ 
 tions. i2mo, cloth.3/6 
 
 “The chief merit of the work is its practical character. . . . The workers in the trade will 
 speedily discover its merits when they sit down to study it.”— English Mechanic. 
 
 *** The above two works together , strongly half-bound, price 7s. 
 
 SHEET METAL WORKER’S INSTRUCTOR. 
 
 Comprising a Selection of Geometrical Problems and Practical Rules for 
 Describing the Various Patterns Required by Zinc, Sheet-Iron, Copper, and 
 Tin-Plate Workers. By Reuben Henry Warn. New Edition, Revised and 
 greatly Enlarged by Joseph G. Horner, A.M.I.M.E. Crown 8vo, 254 pp., 
 with 430 Illustrations, cloth. [Just Published. J/Q 
 
 BREAD & BISCUIT BAKER’S & SUGAR=B01LER’S 
 
 ASSISTANT. 
 
 Including a large variety of Modern Recipes. With Remarks on the Art of 
 Bread-making. By Robert Wells. Third Edition. Crown 8vo, cloth . 2/0 
 “ A large number of wrinkles for the ordinary cook, as well as the baker.”— Saturday Review. 
 
 PASTRYCOOK & CONFECTIONER’S GUIDE. 
 
 For Hotels, Restaurants, and the Trade in general, adapted also for Family 
 Use. By R. Wells, Author of “ The Bread and Biscuit Baker.” Crown 8vo, 
 
 cloth.2/0 
 
 “ We cannot speak too highly of this really excellent work. In these days of keen competition 
 our readers cannot do better than purchase this book."— Baker s Times. 
 
 ORNAMENTAL CONFECTIONERY. 
 
 A Guide for Bakers, Confectioners and Pastrycooks ; including a variety of 
 Modern Recipes, and Remarks on Decorative and Coloured Work. With 129 
 Original Designs. By Robert Wells. Second Edition. Crown 8vo . 5/0 
 “A valuable work, practical, and should be in the hands of every baker and confectioner. 
 The illustrative designs are alone worth treble the amount charged for the whole work.” — Baker's 
 Times. 
 
 THE MODERN FLOUR CONFECTIONER, WHOLESALE 
 
 & RETAIL. 
 
 Containing a large Collection of Recipes f o Cheap Cakes, Biscuits, &c. With 
 remarks on the Ingredients Used in their Manufacture. By Robert Wells, 
 Author of “ The Bread and Biscuit Baker,” &c. Crown 8vo, cloth . 2/0 
 
 “ The work is of a decidedly practical character, and in every recipe regard is had to economical 
 working."— North British Daily Mail. 
 
 LAUNDRY MANAGEMENT. 
 
 A Handbook for Use in Private and Public Laundries. By the Editor of 
 
 “ The Laundry Journal.” Third Edition. Crown 8vo, cloth.2/0 
 
 “ This book should certainly occupy an honoured place on the shelves of all housekeepers 
 who wish to keep themselves au courant of the newest appliances and methods."— The Queen. 
 
4 ° 
 
 CROSBY LOCKWOOD &■ SON'S CATALOGUE. 
 
 HANDYB00K8 FOR HANDICRAFTS. 
 
 BY PAUL N. HASLUCK. 
 
 Editor of “ Work ” (New Series), Author of “ Lathe Work,” “ Milling Machines,” &c. 
 Crown 8vo, 144 pp., cloth, price is. each. 
 
 QfST~ These Handvbooks have been written to supply information for Workmen. 
 Students, and Amateurs in the several Handicrafts, on the actual Practice of 
 the Workshop, and are intended to convey in plain language Technical Know¬ 
 ledge of the several Crafts. In describing the processes employed, and the manipu¬ 
 lation of material, workshop terms are used ; workshop practice is fully explained ; 
 and the text is freely illustrated with drawings of modern tools, appliances, and 
 processes. 
 
 THE METAL TURNER’S HANDYBOOK. 
 
 A Practical Manual for Workers at the Foot-Lathe. With over 100 Illus¬ 
 trations. .10 
 
 “ The book will be of service alike to the amateur and the artisan turner. It displays 
 thorough knowledge of the subject."— Scotsman. 
 
 THE WOOD TURNER’S HANDYBOOK. 
 
 A Practical Manual for Workers at the Lathe. With over ioo Illustrations 
 
 1 o 
 
 “ We recommend the book to young turners and amateurs. A multitude of workmen have 
 hitherto sought in vain for a manual of this special industry.” —Mechanical IVorld. 
 
 THE WATCH JOBBER’S HANDYBOOK. 
 
 A Practical Manual on Cleaning, Repairing, and Adjusting. With upwards of 
 100 Illustrations . . . . . . . . - 1/0 
 
 “ We strongly advise all young persons connected with the watch trade to acquire and study 
 this inexpensive work." —Clerkemvell Chronicle. 
 
 THE PATTERN MAKER’S HANDYBOOK. 
 
 A Practical Manual on the Construction of Patterns for Founders. With 
 
 upwards of ioo Illustrations . . . . . . -1,0 
 
 “ A most valuable, if not indispensable manual for the pattern maker."— Knowledge. 
 
 THE MECHANIC’S WORKSHOP HANDYBOOK. 
 
 A Practical Manual on Mechanical Manipulation, embracing Information 
 on various Handicraft Processes. With Useful Notes and Miscellaneous 
 Memoranda. Comprising about 200 Subjects ...... 1 O 
 
 “A very clever and useful book, which should be found in every workshop; and it should 
 certainly find a place in all technical schools."— Saturday Review. 
 
 THE MODEL ENGINEER’S HANDYBOOK. 
 
 A Practical Manual on the Construction of Model Steam Engines. With 
 
 upwards of 100 Illustrations. ......... 1 O 
 
 “ Mr. Hasluck has produced a very good little book."— Builder. 
 
 THE CLOCK JOBBER’S HANDYBOOK. 
 
 A Practical Manual on Cleaning, Repairing, and Adjusting. With upwards of 
 100 Illustrations ............ 1/0 
 
 “ It is of inestimable service to those commencing the trade."— Coventry Standard. 
 
 THE CABINET MAKER’S HANDYBOOK. 
 
 A Practical Manual on the Tools, Materials, Appliances, and Processes 
 employed in Cabinet Work. With upwards of 100 Illustrations . - 1/0 
 
 “Mr. Hasluck's thorough-going little Handybook is amongst the most practical guides we 
 have seen for beginners in cabinet-work.”— Saturday Rcvinu. 
 
 THE WOODWORKER’S HANDYBOOK OF MANUAL 
 
 INSTRUCTION. 
 
 Embracing Information on the Tools, Materials, Appliances and Processes 
 Employed in Woodworking. With 104 Illustrations. . . . - 1/0 
 
 Opinions of the Press. 
 
 " Written by a man who knows, not only how work ought to be done, but how to do it, and 
 how to convey his knowledge to others."— Engineering. 
 
 “ Mr. Hasluck writes admirably, and gives complete instructions.”— Engineer. 
 
 “ Mr. Hasluck combines the experience of a practical teacher with the manipulative skill and 
 scientific knowledge of processes of the trained mechanician, and the manuals are marvels of what 
 can be produced at a popular price.”— Schoolmaster. 
 
 “ Helpful to workmen of all ages and degrees of experience." —Daily Chronicle. 
 
 “ Practical, sensible, and remarkably cheap.” —Journal 0/Education. 
 
 “Concise, clear, and practical.” —Saturday Review. 
 
COMMERCE , COUNTING-HOUSE WORK , TABLES, &c. 41 
 
 COMMERCE, COUNTING-HOUSE WORK, 
 TABLES, &c. 
 
 LESSONS IN COMMERCE. 
 
 By Professor R. Gambaro, of the Royal High Commercial School at Genoa. 
 Edited and Revised by James Gault, Professor of Commerce and Commercial 
 Law in King’s College, London. Second Edition, Revised. Crown 8vo . 3/6 
 “ The publishers of this work have rendered considerable service to the cause of commercial 
 education by the opportune production of this volume. . . . The work is peculiarly acceptable to 
 English readers and an admirable addition to existing class books. In a phrase, we think the work 
 attains its object in furnishing a brief account of those laws and customs of British trade with which 
 the commercial man interested therein should be familiar.” —Chamber of Commerce Journal. 
 
 “An invaluable guide in the hands of those who are preparing for a commercial career, and, 
 in fact, the information it contains on matters of business should be impressed on every one."— 
 Counting House. 
 
 THE FOREIGN COMMERCIAL CORRESPONDENT. 
 
 Being Aids to Commercial Correspondence in Five Languages—English, 
 French, German, Italian, and Spanish. By Conrad E. Baker. Second 
 Edition. Crown 8vo, cloth . . . . . . . . .3/6 
 
 “ Whoever wishes to correspond in all the languages mentioned by Mr. Baker cannot do 
 better than study this work, the materials of which are excellent and conveniently arranged. They 
 consist not of entire specimen letters, but—what are far more useful- short passages, sentences, or 
 phrases expressing the same general idea in various forms."— Athenceum. 
 
 “ A careful examination has convinced us that it is unusually complete, well arranged and 
 reliable. The book is a thoroughly good one."— Schoolmaster. 
 
 A NEW BOOK OF COMMERCIAL FRENCH. 
 
 Grammar — Vocabulary — Correspondence — Commercial Documents — Geo¬ 
 graphy—Arithmetic—Lexicon. By P. Carroue, Professor in the City High 
 School J.—B. Say (Paris). Crown 8vo, cloth ...... 4/6 
 
 “ M. Carroue's book is a -jade me cum of commercial French, and would be distinctly in its 
 place in every merchant's office. Nothing better could be desired."— Educational Times. 
 
 FACTORY ACCOUNTS: their PRINCIPLES & PRACTICE. 
 
 A Handbook for Accountants and Manufacturers, with Appendices on the 
 Nomenclature of Machine Details; the Income Tax Acts; the Rating of 
 Factories; Fire and Boiler Insurance ; the Factory and Workshop Acts, &c., 
 including also a Glossary of Terms and a large number of Specimen Rulings. 
 By Emile Garcke and J. M. Fells. Fourth Edition, Revised and Enlarged. 
 Demy 8vo, 250 pp., strongly bound ........ 6/0 
 
 " A very interesting description of the requirements of Factory Accounts. . . . The principle 
 of assimilating the Factory Accounts to the general commercial books is one which we thoroughly 
 agree with."— Accountants' Journal. 
 
 “Characterised by extreme thoroughness. There are few owners of factories who would not 
 derive great benefit from the perusal of this most admirable work."— Local Government Chronicle 
 
 MODERN METROLOGY. 
 
 A Manual of the Metrical Units and Systems of the present Century. With 
 an Appendix containing a proposed English System. By Lowis D. A. 
 Jackson, A. M. Inst. C. E., Author of “Aid to Survey Practice,” &c. Large 
 
 crown 8vo, cloth.12/6 
 
 “ We recommend the work to all interested in the practical reform of our weights and 
 measu res."— Nature. 
 
 A SERIES OF METRIC TABLES. 
 
 In which the British Standard Measures and Weights are compared with those 
 of the Metric System at present in Use on the Continent. ByC. H. Dowling, 
 C.E. 8vo, strongly bound .. 10/6 
 
 “ Mr. Dowling's Tables are well put together as a ready reckoner for the conversion of one 
 system into the other."— Athenceum. 
 
 THE IRON AND METAL TRADES’ COMPANION. 
 
 For Expeditiously Ascertaining the Value of any Goods bought or sold by 
 Weight, from is. per cwt. to 112s. per cwt., and from one farthing per pound to 
 one shilling per pound. By Thomas Downie. 396 pp., leather . . 9/0 
 
 “ A most useful set of tables, nothing like them before existed." —Building News. 
 
 " Although specially adapted to the iron and metal trades, the tables will be found useful in 
 every other business in which merchandise is bought and sold by weight ."—Railway News. 
 
42 
 
 CROSBY LOCKWOOD &> SON'S CATALOGUE. 
 
 NUMBER, WEIGHT, AND FRACTIONAL CALCULATOR. 
 
 Containing upwards of 250,000 Separate Calculations, showing at a Glance the 
 Value at 422 Different Rates, ranging from y^th of a Penny to 20s. each, or per 
 cwt., and £20 per ton, of any number of articles consecutively, from 1 to 470. 
 Any number of cwts., qrs., and lbs., from 1 cwt. to 470 cwts. Any number of 
 tons, cwts., qrs., and lbs., from 1 to 1,000 tons. By William Chadwick, 
 Public Accountant. Third Edition, Revised. 8vo, strongly bound . 18 0 
 
 “It is as easy of reference for any answer or any number of answers as a dictionary. For 
 making up accounts or estimates the book must prove invaluable to all who have any considerable 
 quantity of calculations involving price and measure in any combination to do.”— Engineer. 
 
 “ The most perfect work of the kind yet prepared ."—Glasgow Herald. 
 
 THE WEIGHT CALCULATOR. 
 
 Being a Series of Tables upon a New and Comprehensive Plan, exhibiting at 
 one Reference the exact Value of any Weight from 1 lb. to 15 tons, at 300 
 Progressive Rates, from id. to 168s. per cwt., and containing 186,000 Direct 
 Answers, which, with their Combinations, consisting of a single addition 
 (mostly to be performed at sight), will afford an aggregate of 10,266,000 
 Answers ; the whole being calculated and designed to ensure correctness and 
 promote despatch. By Henry Harden, Accountant. Fifth Edition, carefully 
 Corrected. Royal 8vo, strongly half-bound. £1 5 S . 
 
 “ A practical and useful work of reference for men of business generally.”— Iro7imonger. 
 
 “Of priceless value to business men. It is a necessary book in all mercantile offices.”— 
 Sheffield Independent. 
 
 THE DISCOUNT GUIDE. 
 
 Comprising several Series of Tables for the Use of Merchants, Manufacturers, 
 Ironmongers, and Others, by which maybe ascertained the Exact Profit arising 
 from any mode of using Discounts, either in the Purchase or Sale of Goods, and 
 t)ie method of either Altering a Rate of Discount, or Advancing a Price, so as 
 to produce, by one operation, a sum that will realise any required Profit after 
 allowing one or more Discounts : to which are added Tables of Profit or 
 Advance from i\ to 90 per cent., Tables of Discount from i| to 98^ per cent., 
 and Tables of Commission, &c., from § to 10 per cent. By Henry Harben, 
 Accountant. New Edition, Corrected. Demy 8vo, half-bound . £1 5s. 
 
 “ A book such as this can only be appreciated by business men, to whom the saving of time 
 means saving of money. The work must prove of great value to merchants, manufacturers, and 
 general traders .”—British Trade Journal. 
 
 DIRECT CALCULATORS. 
 
 A Series of Tables and Calculations varied in Arrangement to Suit the Needs 
 of Particular Trades. By M. B. Cotsworth. The Series comprises 13 
 distinct Books, at prices ranging from 2/6 to 1 0/6- (Detailed prospectus on 
 application.) 
 
 TABLES OF WAGES. 
 
 At 54, 52, 50 and 48 Hours per Week. Showing the Amounts of Wages from 
 One-quarter-of-an-hour to Sixty-four hours, in each case at Rates of Wages 
 advancing by One Shilling from 4s. to 55s. per week. By Thos. Garbutt, 
 Accountant. Square crown 8vo, half-bound. 6/0 
 
 IRON = PLATE WEIGHT TABLES. 
 
 For Iron Shipbuilders, Engineers, and Iron Merchants. Containing the 
 Calculated Weights of upwards of 150,000 different sizes of Iron Plates from 
 I foot by 6 in. by J in. to 10 feet by 5 feet by 1 in. Worked out on the Basis of 
 40 lbs. to the square foot of Iron of 1 inch in thickness. By H. Burlinson 
 and W. H. Simpson. 4to, half-bound . £1 5s. 
 
 MATHEMATICAL TABLES (ACTUARIAL). 
 
 Comprising Commutation and Conversion Tables, Logarithms, Cologarithms, 
 Antilogarithms and Reciprocals. By J. W. Gordon. Royal 8vo, mounted 
 on canvas, in cloth case. [Just Published. 5/0 
 
AGRICULTURE, FARMING, GARDENING, &c. 
 
 43 
 
 AGRICULTURE, FARMING, 
 GARDENING, &c. 
 
 THE COMPLETE GRAZIER AND FARMER’S AND 
 
 CATTLE BREEDER’S ASSISTANT. 
 
 A Compendium of Husbandry. Originally Written by William Youatt. 
 Thirteenth Edition, entirely Re-written, considerably Enlarged, and brought 
 up to the Present Requirements of Agricultural Practice, by William 
 Fream, LL.D., Steven Lecturer in the University of Edinburgh, Author of 
 “The Elements of Agriculture,” &c. Royal 8vo, 1,100 pp., with over 
 450 Illustrations, strongly and handsomely bound . . . £1 11 s. Gd. 
 
 Extract from Publishers’ Advertisement. 
 
 “A treatise that made its original appearance in the first decade of the century, and that 
 enters upon its Thirteenth Edition before the century has run its course, has undoubtedly 
 established its position as a work of pennanent value. . . . The phenomenal progress of the 
 
 last dozen years in the Practice and Science of Farming has rendered it necessary, however, that 
 the volume should be re-written, . . . and for this undertaking the Publishers were fortunate 
 
 enough to secure the services of Dr. FREAM, whose high attainments in all matters pertaining to 
 agriculture have been so emphatically recognised by the highest professional and official authorities. 
 In carrying out his editorial duties, Dr. FREAM has been favoured with valuable contributions by 
 Prof. J. Wortlev AXE. Mr. E. BROWN, Dr. BERNARD DYER, Mr. W. J. MALDEN, Mr. R. H. 
 Rew, Prof. Sheldon. Mr. J. Sinclair, Mr. Sanders Spencer, and others. 
 
 "As regards the illustrations of the work, no pains have been spared to make them as 
 representative and characteristic as possible, so as to be practically useful to the Farmer and 
 Grazier.” 
 
 Summary of Contents. 
 
 Book I. On the Varieties, Breeding, 
 Rearing, Fattening and Manage¬ 
 ment of Cattle. 
 
 Book II. On the Economy and Man¬ 
 agement of the Dairy. 
 
 Book hi. On the Breeding, Rearing, 
 and Management of Horses. 
 
 Book IV. On the Breeding, Rearing, 
 and Fattening of Sheep. 
 
 Book V. On the Breeding, Rearing, 
 and Fattening of Swine. 
 
 Book VI. on the Diseases of Live 
 Stock. 
 
 Book vii. On the Breeding, Rearing, 
 and Management of Poultry. 
 
 Book viii. On Farm Offices and 
 Implements of Husbandry. 
 
 Book IX. On the Culture and Man¬ 
 agement of Grass Lands. 
 
 Book X. On the Cultivation and 
 Application of Grasses, pulse and 
 Roots. 
 
 Book XI. On Manures and their 
 Application to Grass Land and 
 Crops. 
 
 Book xii. monthly Calendars of 
 Farmwork. 
 
 *** Opinions of the Press on the New Edition. 
 
 “ Dr. Fream is to be congratulated on the successful attempt he has made to give us a work 
 which will at once become the standard classic of the farm practice of the country. We believe 
 that it will be found that it has no compeer among the many works at present in existence. . . 
 
 The illustrations are admirable, while the frontispiece, which represents the well-known bull, 
 New Year's Gift, bred by the Queen, is a work of art.”— The Times 
 
 “ The book must be recognised as occupying the proud position of the most exhaustive work 
 of reference in the English language on the subject with which it deals.”— Athenceujn. 
 
 “ The most comprehensive guide to modern farm practice that exists in the English language 
 to-day. ... The book is one that ought to be on every farm and in the library of every land 
 owner."— Mark Lane Express. 
 
 “In point of exhaustiveness and accuracy the work will certainly hold a pre-eminent and 
 unique position among books dealing with scientific agricultural practice. It is, in fact, an agricul¬ 
 tural library of itself.”— North British Agriculturist. 
 
 “ A compendium of authoritative and well-ordered knowledge on every conceivable branch of 
 the work of the live stock farmer; probably without an equal in this or any other country."— 
 Yorkshire Post. 
 
 “ The best and brightest guide to the practice of husbandry: one that has no superior—no 
 equal we might truly say—among the agricultural literature now before the public. . . . In every 
 
 section in which we have tested it, the work has been found thoroughly up to date.”— Bell's Weekly 
 Messenger 
 
 FARM LIVE STOCK OF GREAT BRITAIN. 
 
 By Robert Wallace, F.L.S., F.R.S.E., &c., Professor of Agriculture and 
 Rural Economy in the University of Edinburgh. Third Edition, thoroughly 
 Revised and considerably Enlarged. With over 120 Phototypes of Prize 
 Stock. Demy 8vo, 384 pp., with 79 Plates and Maps, cloth. . . 1 2/G 
 
 “A really complete work on the history, breeds, and management of the farm stock of Great 
 Britain, and one which is likely to find its way to the shelves of every country gentleman’s library.” 
 — The Times. 
 
 “The latest edition of ‘ Farm Live Stock of Great Britain ’ is a production to be proud of, and 
 its issue not the least of the services which its author has rendered to agricultural science.”— 
 Scottish Farmer. 
 
 “The book is very attractive, . . . and we can scarcely imagine the existence of a 
 
 farmer who would not like to have a copy of this beautiful and useful work.”— Mark Lane Express. 
 
 “A work which will long be regarded as a standard authority whenever a concise history 
 and description of the breeds of live stock in the British Isles is required— Bell's Weekly 
 Messenger. 
 
44 
 
 CROSBY LOCKWOOD & SON'S CATALOGUE, 
 
 BRITISH DAIRYING. 
 
 A Handy Volume on the Work of the Dairy-Farm. For the Use of Technical 
 Instruction Classes, Students in Agricultural Colleges and the Working Dairy- 
 Farmer. By Prof. J. P. Sheldon. With Illustrations. Second Edition, 
 Revised. Crown 8vo, cloth. [ Just Published. 2/6 
 
 " Confidently recommended as a useful text-book on dairy farming ."—Agricultural Gazette, 
 “ Probably the best half-crown manual on dairy work that has yet been produced .”—North 
 British Agricultu rist. 
 
 "It is the soundest little v/ork we have yet seen on the subject ."—The Times. 
 
 MILK, CHEESE, AND BUTTER. 
 
 A Practical Handbook on their Properties and the Processes of their Produc¬ 
 tion. Including a Chapter on Cream and the Methods of its Separation from 
 Milk. By John Oliver, late Principal of the Western Dairy Institute, 
 Berkeley. With Coloured Plates and 200 Illustrations. Crown 8vo, cloth. 
 
 7/6 
 
 " An exhaustive and masterly production. It may be cordially recommended to all students 
 and practitioners of dairy science ."—North British Agriculturist. 
 
 " We recommend this very comprehensive and carefully-written book to dairy-farmers and 
 students of dairying. It is a distinct acquisition to the library of the agriculturist ."—Agricultural 
 Gazette 
 
 NOTE = BOOK OF AGRICULTURAL FACTS & FIGURES 
 
 FOR FARMERS AND FARM STUDENTS. 
 
 By Primrose McConnell, B.Sc. Fifth Edition. Royal 32mo, roan, gilt 
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