restell’s lock.

597

locking-pin, and in the application of a compoundmotion to the tumblers, the effect of which is, thatby once turning round the key a double or triplelocking may be produced.

Fourthly.—In the adaptation of a dial or indi-cator to tumbler locks, whereby the changes of thetumbler may be varied according to the permuta-tions of a moveable bit-key, or whereby, in com-bination with other apparatus, the positions of theparts of the lock may be so arranged after the actof locking as to prevent the possibility of the lockbeing opened, even with the legitimate key, withoutthe knowledge of the secret arrangement.

Fifthly.—In dispensing with the shackle and eye-bolt of padlocks, or either of them, and in causingthe bolt of the lock to be held, and the lockingeffected by means of pins or projections on, or holesor recesses formed in, a plate of metal to which thelock is attached.

Restell’s Lock, Patent dated December 8th, 1851.

The principal feature in the construction of thislock consists in constructing the keyhole in sucha manner, as that not more than one instrumentcan be introduced into the lock at one time forthe purpose of picking it; and, further, that ifany instrument other than the proper key be intro-duced, and turned partly round, it will meet withan obstruction, as usual in all combination locks,but cannot be withdrawn therefrom until all the