After stating the facts in the case as above, GROSSGUP, Circuit Judge, delivered the opinion of the court, as follows:
The object of the invention described in the patent in suit is to substitute for cash boys and girls formerly employed in retail stores a simple, efficient, and reliable apparatus, by which cash or small parcels can be conveyed from the sales station to the cashier’s desk, and the change returned to the sales station.
It is not claimed that, in the promotion of the general purpose, the patent is, in any sense, a primary one. It is admitted that the general object in view had been previously realized, and that the patentee came into the art, not as a creator, but as an improver The claim is that his system excels all its predecessors for cheapness, simplicity and efficiency. These constitute the scope of the appellant’s improvement.
But these are results simply. It is somewhat difficult to point out, in the appellant’s apparatus, the mechanical means leading to these results. They may, however, with sufficient accuracy, he summarized as follows: (a) The use of a slender wire, instead of a metal rail, or a wire rail; (b) the use of straining nuts, placed at each end of the wire, so that the wire may be tightened, from time to time, to keep it stretched perfectly taut; (c) the attachment of the car to the wire, so rigidly that oscillation, in the line with the car’s movement, will be prevented, resulting in the car’s being propelled from end to end by a single impulse.
It is plain to ns that the employment of the two features first named, either singly or together, cannot be treated as importing novelty into the appellant’s patent. The use of nuts to stretch the wire is not mentioned, either in the claims or the specifications; and the proceedings in the Patent Office, in connection with the formulation of the claims, exclude the inventor’s selection of wire, as distinguished from some other form of rail, from being considered as a novel feature of the claims of the patent. The inventor first claimed broadly, “wires stretched horizontally from a suitable point or points in the store center, forming suspended ways upon which cars are mounted by means of wheels”; hut this claim, as we have seen, went out before the patent was allowed. The only reference to wire in the claim allowed is in combination with a freely moving car. This, we think, eliminates the selection of a slender wire — as distinguished from a rail or wire rail — from a place, as an independent factor, in the grant to appellant. It may be that *984wire, as a track, was not in nse in that- art formerly, and that its' selection by the patentee was in the nature of a meritorious discovery; but courts will not, in the absence of an inclusive claim, go into the history of the art, to ascertain what was really discovered, and what might have been patented, had the patentee chosen. The patentee will be taken at his word, and protected only according to the terms in which he has himself demanded protection.
The real invention, then, if any, embodied in the patent under discussion is in the attachment of the car to a wire so rigidly, that oscillation is prevented. It is this conception — possibly new — in combination with the old parts of the apparatus, that gives to the claim its validity, if it have any.
It may be assumed that the patentee discovered that the hindrance to the easy propulsion of a car long distances on a wire, by a single impulse, was in the oscillatory movement of the car, where it hung loosely on the wire; but this discovery, however important, is not, as a discovery, included in the patent. The mechanical means of overcoming thé hindrance is the subject-matter of the patent; and these means are described, in the specifications, as a car suspended beneath the wire on wheels, one behind the other, by means of hangers which form a frame for the wheels; and, in the claim, as a freely moving car held below the wire on wheel-hangers. The discovery actually embodied in the patent, therefore, is not that oscillation, in line with the wire, is a hindrance to the propulsion of a car, but that a car hung rigidly under the wire, on two wheels upon the wire, one behind the other, will overcome such oscillation. The scope of the patentee’s grant embraces, not every means of overcoming this apprehended oscillation, but only such as are set forth in the patent.
However the merits of the patentee’s contribution might incline us, we have no power to enlarge his patent. Restricted to the limits already indicated, it cannot, by judicial interpretation, be made to cover the appellee’s device. That device obviates oscillation, and procures rigidity, through mechanical means, different from the patent in suit.
As already stated, appellant’s apparatus consists of a car suspended beneath a wire or way from two wheels running upon the wire, and at opposite ends of the frame, one behind ‘the other, and cooperating equally in sustaining the weight. The frame is rigidly attached to the wheels, for the primary purpose of preventing oscillation, in the line of the car’s travel.
In the appellees’ apparatus the car is suspended beneath the wire or way by one wheel only, upon the wire, and near the middle of the car, which wheel alone sustains the weight. Beneath the wire, and at one end of the car, however, is a second wheel, which Serves the purpose of preventing oscillation, in the line of the car’s travel.
In appellant’s apparatus the weight conveyed is between the wheels, and, since the two wheels cooperate equally in sustaining the load, either may be treated as the fulcrum, the other being, in turn, the motive power, and the preventive against oscillation; while in appellees’ apparatus the weight is on one end of the frame, the *985fulcrum is in the center, and the motive power, and the preventive against oscillation, at the other.
Appellant must employ a frame of sufficient length — for the primary purpose of preventing oscillation — to preclude the forward end of the frame from an upward movement, in response to the initial impulse. This length of frame depends, of course, in each instance, upon the approximate weight of the parcel to he carried. Any undue attempt to shorten the length of frame, thus throwing the wheels close together, would eliminate the advantage against oscillation gained from an appropriate length of frame.
The mechanical construction, on the contrary, of appellees’ apparatus admits of a placing of the wheels as close to each other as may he desired. The one wheel being under the wire and the other above, rigidity — non-oscillation—is preserved, not by length of frame proportionate to the weight and impulse, hut by the fact that flu: position of the wheels is such, that one counteracts the other. In our opinion there is no infringement.
The decree of the Circuit Court will be affirmed.