In 1829 Mr. Gottlieb took out a patent for improvements in locks, which consisted in the application of a piece of paper over the key-hole, so secured as to prevent its being removed without the introduction of a key passing through it ; and hence any attempt to break open the lock would be indicated by the fracture of the paper. The paper is introduced and secured by means of a folding shield with • hole in it, similar to the key-hole, in a lock plate ; this shield is kept down by a spring catch, which cannot be disengaged for the introduction of a fresh piece of paper, except by the proper key, which is furnished with a projecting stud on the side of the key-stem, for the purpose of disengaging the shield catch when turned. As a source of further security, the patentee pro- to employ checque-paper, with some design engraved upon it; and by having this paper bound in a checque-book, leaf torn off when required, so that thepaper found in the key-hole at any time being compared with the edge of the leaf in the book, the substitution of another paper would be discovered. There are few cases in which this plan can be advantageously employed.
Messrs. Carpenter and Young, of Willenhall, in Staffordshire, had a patent in 1830 for improvements in locks. Their object appears, from the specification, to be the production of locks of greater security and stability than the common locks without augmenting the cost; and also to construct a latch-lock, some what more convenient in use. The greater degree of security is obtained by having a double set of tumblers, one set attached to, and movable with, the bolt, and the other attached to the plate of the lock in the usual way. Pro jections from the stationary tumblers fit into slits in the movable ones, when they are simultaneously elevated to a given position ; and in addition to this, there are notches cut in the upper and lower sides of the movable tumblers, to fit fixed pins projecting from the plate, just above the notches on the upper side, and just below those of the under side when the door is locked, so the bolt cannot be withdrawn except by a key, which raises each tumbler to an elevation coinciding precisely with the cuts in the original key, and upon this depends the security. Instead of the usual latch or spring bolt to room-door locks, the patentees cause this part to drop into a notch in the striking plate after it has been elevated by passing over an inclined plane upon it. In con nexion with this latch is a tumbler, by which it is elevated through the instru mentality of a key, by a handle on one side of the door and a key on the other, , or by the key, without using the handle. These contrivances have manifest advantages, and are easily executed by any locksmith.
The application of an inviolable lock to boxes sent by mails or other convey ance, containing money or other valuable property, that can be opened only at stated times, is, of course, an object of desirable attainment in a commercial country like this. For effecting this object a patent was taken out in November, 1831, by William Rutherford, jun. of Jedburgh, in Scotland. This gentleman being a bank agent, had no doubt sensibly felt the importance of having the means of transmitting, from one town to another, bankers' parcels with perfect safety. With this view he introduces against the end of the bolt a circular stop-plate, to prevent the withdrawal of the bolt till the circular plate, which is put in rotation by clock-work, shall have revolved so as to bring a notch oppo site the end of the bolt. Now as this notch can be set at pleasure to any required distance from the end of the bolt, the lock may be secured against being opened by its own or any other key, till any assigned number of hours after it has been locked ; and as the rate of travelling is known, the box can be secured from robbery till it shall have reached its destination. When this fastening is used for portable boxes or packages, it must be put in motion, and its motion regulated by springs ; but when it is to be applied to closets or safes, the most simple mode of giving motion will be by a descending weight, and of regulation by a pendulum ; the actuating weight may then be made to rest upon, and disengage a locking bar in connexion with the bolt of the lock, at any assigned number of hours after the fastening has been effected. In this
case all that is necessary is to cause the weight to descend down a vertical scale, divided into hours, and to raise it to any assigned number when the door is locked. A still farther security is obtained by the locking-bar itself being pre vented from being disengaged by any pressure, except by the descent of the weight, which is made to come, in its descent, into contact with an inclined pro jection from the lower end of the'hour-scale, sending it back and disengaging the locking-bar from a notch therein.
We might extend our descriptive account of locks to numerous others, con taining arrangements of parts differing from the foregoing, and each possessing a certain degree of merit, as respects one or more of the necessary qualifica tions of a lock ; but the detail would be uninteresting and profitless ; we shall, therefore here close our account of locks extraordinary, by giving the reader a summary of those in general use, of which there are full a hundred times as many as of the former. Indeed, by far the greater number of locks in use are not required as a security against the dexterous thief, but principally as a check upon the intrusive curiosity and meddling of children and servants ; and of the numerous tribe of petty pilferers, there are few who have sufficient knowledge of the nature of common-locks to succeed in, or who aro daring enough to attempt the picking of them. We have already noticed, at page 104, that a vast quantity of locks are made without any wards or other securities whatever, but the bolt; and these having been stamped with the public approbation, our own know ledge for nearly half a century,) what need is there to give two guineas, or two shillings for a lock, when a satisfactory one can be obtained for two-pence ? Useful trunk locks are indeed manufactured by thousands of grosses, at a wholesale price not exceeding one each ! They are chiefly the product of the stamping press ; but the malleable-cut-iron-founder is not behind-hand in demonstrating the power of his art in this manufacture. The technical term for wards, m the lock-trade is wheels; thus, they are successively demonstrated according to this point of their quality, 1 wheel, 2 wheels, 3 wheels, 4 wheels; and to these terms there is a prefixture called plain, which means, no wards at all. The wards are simply short pieces of thin plate iron, rivetted en the upper or lower plate, or on both plates, opposite or near to the key hole. If the wards are of a better quality, they are dignified by a higher title, as one ward round, i two wards round, &c.; which is when the wards make an entire circle, or nearly so, of the lock. They are called L ward, or T ward, or z ward, when the sectional form of the wards represents the figure of those letters. Copper wards, signify the employment of that metal, instead of iron, to adapt them for use in cellars, and other damp places. Solid wards are much used, as they are substantial and not dear, being readily made by casting in brass, and turning in the lathe; and they largely assist in making fancy locks. The term fine, in the lock trade, has about the same meaning as the ordinary application of that adjective to smart persons; they are a little glazed on the surface, to dazzle the eye, but are coarse enough underneath; and they have two bright-headed screws, one or both of which are usually loose. The quality of the plates, bridges, staples, springs, bolts, and other parU of the interior of a lock, is made to assimilate with the quality of the wands, unless ordered to the contrary.