Within the past two years ('96 and '97) locks made entirely from wrought materials by machinery and interchangeable in all parts have been placed on the market, which appear to mark a new step in the improvement of the ordinary lock.
At the present time the Yale "Vulcan "locks are, to the best knowledge of the author, the only locks that are made entirely of wrought metal, although the new Warner locks are all of wrought metal except the hub and bolt heads.
Fig. 372. - Anti-Friction
In the Vulcan lock (made by the Yale and Towne Manufacturing Co.) the front is formed of a base of wrought steel with beveled edges, over which is drawn a cover of wrought bronze, clinched over the edges and fitted so nicely as to appear like one piece of metal. The bolts also are all of wrought metal, the head consisting of a solid piece of wrought bronze or steel with the tail piece forged into it.
The exterior of the Vulcan lock is shown in Fig. 397, and the action of the dead and latch bolts in Figs. 369 and 371. The cycloid knob action of this lock is an entirely new principle in lock mechanism. These locks are made with great nicety, so that all the parts fit together perfectly, while the bearings are so broad that there can be but little, if any, wear on the various parts, more especially on the hub. The Warner locks are also very nicely made, and although the bearings are not as broad as in the Vulcan locks, they are a great advance over the common cast lock.
It is probable that within a few years machine-made locks, entirely of wrought metal, will wholly take the place of the ordinary cast lock, as with the proper machinery a better quality of lock can be made at no greater, and possibly at less expense.