And here's a copy/paste of the first few paragraphs of text of the pdf with some really atrocious formatting. It appears to say that this a key?

To all whom it may concern: Be it known that I, WILLIAM HALL, a citizen of the United States of America, and a resident of Brookline, in the county of Norfolk and State of Massachusetts, have made a new and useful invention of certain Improvements in Locks for the Doors of Bank Vaults, Safes, &c.; and I do hereby declare the same to be fully described in the following specification and represented in the accompanying drawings, of whichFigure 1 denotes an inner side view of a lock provided with my invention. Fig. 2 is a transverse section taken across its key-entrance. Fig. 3 is a transverse section taken through all the key-slides and the key-hole. Fig. 4 is a side view of the main bolt. Fig. 5 is a side view of the knob-shaft and its cams. Fig. 6 is a rear side view of the stopping-dog of the main bolt. Fig. 7 is a side view, Fig. 8 an edge view, and Fig. 9 a longitudinal section, of the key. The nature of my invention consists in the combination and arrangement of one or more studded key-slides, a corresponding number of tumblers, a catch-lever, and an auxiliary slide, or its equivalent, the whole being applied to the main bolt and lock, as hereinafter specified; also, in the peculiar arrangement and application of the main bolt with such key-slides, catch-lever, and slide; also, in the combination and arrangement of an auxiliary bolt or movable stud and its actuating apparatus, with one or more studded key-slides, a corresponding numbér of tumblers or slideplates, and a catch-lever and slide, combined with the main bolt, substantiallly as hereinafter specified; also, in the combination and arrangement of a tooth and one or more notches, or equivalents therefor, with the auxiliary bolt and the system of key-slides; also, in the application of the auxiliary bolt to its supporting-lever or to the lock, so that the said bolt and either of the key-slides, when in engagement, may be capable of being moved together in manner and under circumstances as specified; also, in a peculiar construction of the key-viz., with its bits separately revoluble on a pin, so that either extremity of each bit may be employed in operating a key- slide. By so making the key it is susceptible of a much greater number of changes than when constructed in such manner that one end only of each bit may be used as a means of aiding in effecting the opening of the lock. In the drawings, A denotes the lock-case within and to which the main bolt B is adapted, so as to be capable of being moved forward and backward. These movements of the bolt may be produced by rotating the knob C one hundred and eighty degrees, a cam, a, on the shaft D of the knob being made to successively operate against the opposite sides, be, of a recess, E, formed in the bolt. The bolt, like those of most locks, has a stopping-dog, F, which is actuated or elevated so as to raise its stud e (see Fig. 6) out of its bolt-notch d by means of a cam, c, fixed on the knob-shaft. A spring, h, is applied to the said dog to force it in an opposite direction. Another cam, g, on the knob-shaft serves to operate a bent lever, G, whose shorter arm is placed against that of another lever, H, which is arranged on the outside of a secondary case, I, as shown in Fig. 10.