tag="{http://www.w3.org/1999/xhtml}a">[5] If the pin-lock was in use in ancient Egypt it was certainly exceptional, as all the sculptures represent the doors as being fastened by simple bolts.

Whether the modern Egyptian lock is a survival of an ancient Egyptian form, or whether it is of Roman origin, it is certain, from the relics of Roman bronze and iron keys and bolts found in various parts of Europe, that the Roman lock was constructed on the same principle. Figs. 15B to 20B, Plate III., may be taken as illustrations of the Roman lock when put together. It is a reproduction from original fragments preserved in the Museum at Mainz. Fig. 20B is the bronze key; it has four teeth which, besides being at variable distances apart, are also of different forms, some being triangular and others square. Fig. 19B is the bronze bolt, made with apertures to fit the key, and also to admit of similarly formed tumblers, shown in fig. 18B. The way in which these are put together is represented in the section of the lock, figs. 16B and 17B. The key a is put into the keyhole d, fig. 15B, with the bar of the key containing the teeth in a vertical position, as represented by the dotted line a, fig. 16B. It is then turned round, and the teeth brought up beneath the bolt b. When pressed up vertically, the tumblers are driven up out of the bolt, and replaced by the teeth of the key, which hold the bolt so that it can be forced back by moving the key to the right. When the bolt is withdrawn, it releases the hasp e, fig. 15B. Of such hasps, fig. 21B is a drawing of an original in my collection, found at Hetternheim. By reference to fig. 16B, it will be seen that the tumblers, f f, are vertical, and would therefore fall into their places in the bolt, like those of the Egyptian and Scandinavian specimens; but being so small, and being probably made of wood, their weight would be insufficient to secure certainty of action, if dependent on weight alone; they are therefore pressed down by a flat plate h, figs. 16B and 17B, acting under the influence of a spring g, figs. 16B and 17B. This is an important addition, for it is evident that as soon as the spring comes into use, the tumblers can easily be made to press into the bolt horizontally, by means of a spring at the side, thereby enabling the lock to be used in any position in which it may be required; and there seems to be little doubt that some of the bolts and tumblers were so constructed in Roman locks. The existence of a spring in Roman locks is determined by the discovery of one with the spring in it, which is figured in M. Liger's work 'La Ferronnerie.'[6]

The teeth of the key of the Roman lock described above, it will be seen, are made to fit exactly the holes in the bolt; and this may perhaps have served to give the first idea of the ward system, which was so greatly depended upon for security in later times; but the same fallacy attaches to the use of these fitting teeth which attached to the ward system generally, for it is evident that any form of tooth small enough to go into the holes, and of the proper length, would have sufficed to lift the tumblers and draw the bolt; and accordingly we find that, in the Roman key usually discovered, the teeth are merely round pins, and have no particular form given to them for fitting purposes.

The distribution of this class of lock may be determined by the localities in which the keys and bolts have been found. Fig. 22B, Plate III., is a bronze bolt of this description in my collection, from Oppenheim, and obtained by me at Mayence. Fig. 23B, Plate III., is another of bronze, also in my collection, from Heddernheim. Similar ones have been found repeatedly in France, Italy, Germany, Switzerland, and England. The keys with teeth are even more widely distributed, and have been found in all those countries which have been occupied by the Romans. Fig. 24B, Plate III., is a large iron key of this description in my collection, found in the Rhine, at Mayence. The earliest known example of a key with teeth, according to M. Liger, is one represented on a coin of the Papia family, dating about the end of the 2nd century B.C.[7]

But the ward system appears to have developed itself still further in connection with these locks and before the revolving key was introduced. Fig. 25B, Plate III., is a specimen of a class of keys frequently discovered with Roman remains, in which a plate is attached at right angles to the pins. This plate is pierced with slits of various forms, apparently intended to admit of the passage of wards placed vertically beneath the bolt to prevent any but the proper key from rising to lift the tumblers. The direction in which these keys were raised is shown by the flat part of the handle of the key being always at right angles to the pins and in the same plane as the ward plate.

Besides the bolts with several tumbler holes in them, others adapted for single tumblers have been discovered. Of these fig. 26B, Plate III., drawn from M. Liger's work, and found in the forest of Compiègne, is an example, and fig. 27B, Plate III., from the same work, and found at Nonfous, in Switzerland (Bonstetten) is a key adapted to fit such a bolt.

Other iron keys are found in England and France, the application of which is more doubtful. They are found chiefly in connection with Celtic remains, and by some have been supposed to be keys for opening doors fastened with a simple latch on the inside.[8] Such latches were certainly employed amongst the earliest systems of door-fastenings, and the keys in question might have served the purpose of opening them, but they might also have been used to open locks with a single wooden tumbler; the simpler kinds resemble somewhat our modern pick-locks, of which fig. 28B, Plate III., is a specimen. Fig. 29B, Plate III., in my collection is from a Germano-Roman tomb near Niderolm, and was obtained at Mayence; its possible use, in the manner represented in fig. 9B, Plate II., is obvious. Figs. 30B and 31B, Plate III., are two Anglo-Saxon keys found at Sarr, in Kent.[9] Figs. 32B, 33B, Plate III., are two keys of the Iron Age from Bornholm, in the Baltic,[10] attributed by M. Videl to the 3rd or 4th century of our era. Fig. 34B, Plate IV., is a somewhat similar one from Caerwent,