Rudimentary Treatise on the Construction of Locks

by A. C. Hobbs; George Dodd

“To John Weale, Esq., 59 High Holborn.”

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 Construction 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 establishments, 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 ‘plant,’ as it is termed, is made upon a house or a bank, precise information is gained, if possible, as to the depository of the valuables; 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 inmates 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 employers 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 initiated 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 carefully re-locked, and not until the bank is opened for business next morning is the robbery discovered.”

In an article in Frazer’s Magazine for November 1852 the following observations were made on the Exhibition Jury Report on Locks: “This jury seems to have consisted of the only persons in England who did not hear of the famous ‘lock controversy’ of last year; for one can hardly imagine that, if they had heard of a matter of so much consequence to the subject they were appointed to investigate, they would have altogether abstained from saying any thing about it. They may be excused 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 which the transatlantic Hobbs gained so much glory, was suggested and explained in the Encyclopædia 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 impregnable.’ 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 discrimination 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 account, 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 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 bank-lock 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 Palace; he had at a previous period been in the employ of Messrs. Bramah. We mention these facts only on account of an erroneous 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. Thomson, and Mr. W. F. Shattuck,—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 during that time the privilege of introducing one associate, and the arbitrators reserving to themselves the right of inspecting the seals placed by them on the box; that, in order to afford every information concerning the internal arrangement 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 proper 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 200l. should be paid to him by Mr. Hobbs.

In accordance with the above agreement, Mr. Hobbs produced a parautoptic lock, with ten tumblers, marked No. 8560. 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 arrangement 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 uninjured, 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 access 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 unopened 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 present 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. Garbutt, 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.