The court below, upon final hearing, dismissed the bill, upon the ground that there was no infringement. The complainant then appealed here.

Mr. Francis Forbes and Mr. Thomas William Clarke for the appellant.

Mr. Benjamin Dean and Mr. J. G. Abbott, contra.

MR. JUSTICE CLIFFORD delivered the opinion of the court. Causes of action arising under the patent laws are originally cognizable, as well in equity as at law, by the circuit courts, or the district courts having the power and jurisdiction of a circuit court, subject to the condition that the final judgment or decree in such a case may be removed here for re-examination.

Improvements were made by William Naylor in steam safetyvalves, for which, on the 16th of October, 1866, he obtained letters-patent of the United States; and it appears that he subsequently assigned the patent to the complainant, and that the complainant, as such assignee, surrendered and obtained the reissued patent which is the foundation of the present suit. Wrongful infringement is charged, and the complainant prays for an account and for an injunction. Service was made; and the respondents appeared and set up certain defences in their answer, as follows: 1. That the reissued patent is not for the same invention as the original. 2. That the assignor of the complainant was not the original and first inventor of the improvement. 3. That the reissued patent does not cover and embrace the safety-valve used by the respondents. 4. That safetyvalves such as are used by the respondents were described and patented in letters-patent granted prior to the patent and supposed invention of the assignor of the complainant, as alleged in the answer.

Proofs were taken, the parties heard, and the Circuit Court entered a final decree dismissing the bill of complaint.

Due appeal was taken by the complainant, and he assigns the following errors: 1. That the court erred in giving weight to the disclaimer of the supposed inventor, as set forth in his English patent. 2. That the court erred in ruling that the patent of the complainant must be limited to claims for a combination of the valve described in the specification, with the annular recess surrounding the central chamber, as explained in the court's opinion. 3. That the court erred in deciding that the assignor of the complainant did not invent the overhanging, downward-curved lip, and that he was not the first to use an annular chamber surrounding the valve-seat, into which a portion of the steam is deflected as it issues between the valve and the seat. 4. That the court erred in deciding that the valve used by the respondents is not within the complainant's reissued patent. 5. That the court erred in deciding that there is a substantial difference between the valve used by the respondents and the valve described in the complainant's reissued patent.

Preliminary to the investigation of the inquiries suggested in

the errors assigned by the appellant, it becomes expedient to ascertain what is the construction of the patent described in the bill of complaint, and whether the same has been infringed by the respondents. Obvious convenience suggests that these two matters be first determined, for the plain reason that, if the proofs fail to establish the charge of infringement, most or all of the errors assigned will become immaterial in disposing of the case.

Persons seeking redress for the unlawful use of letters-patent are obliged to allege and prove that they, or those under whom they claim, are the original and first inventors of the improvement described in the patent, and that the same has been infringed by the party against whom the suit is brought. Both of those allegations must be proved by the party instituting the suit; but where he introduces the patent in evidence, it affords a prima facie presumption that the first allegation is true, and inasmuch as it is not controverted in the answer in this case, the finding in that regard must be in favor of the complainant.

Suppose that is so, still the charge of infringement is denied by the respondents, which issue cannot be satisfactorily determined without first ascertaining the true nature and character of the improvement secured to the complainant in his reissued letters-patent.

Three patents one in England, two in the United States were granted to the complainant or his assignor for the improvement which is the subject of the present controversy. Naylor, it is claimed, was the inventor of the patented improvement, and he took out his first patent in England, where he resided. As the patentee states, the invention relates to certain improvements in safety-valves, and consists, when using a spring for resisting the valve from opening, in the employment of a lever of the first order, one end resting by a suitable pin upon the safety-valve, and the other end of the lever resting upon the spring, the end resting upon the spring being bent downwards to an angle of about forty-five degrees from the fulcrum, so that when the valve is raised by the steam the other end of the lever is depressed upon the spring downwards, and at the same time is moved inwards towards the fulcrum, thus

virtually shortening that end of the lever, and thereby counteracting the additional load upon the valve as it is raised from its seat by the greater amount of compression put upon the spring.

Exceptional modifications in certain features of the improvement are subsequently suggested, and then the patentee proceeds to explain the functions of the different devices by reference to the drawings, in the course of which he states that he prefers to make the valve project over the edges of the exitpassage and to curve the projecting edges of the valve slightly downwards, so that the steam on issuing between the valve and its seat will impinge against the curved projecting part of the valve, which will direct a portion of it downwards into the annular chamber surrounding the central passage, while the other portion of the steam ascends past the edges of the valves. By that means the patentee states that he is enabled to avail himself of the recoil action of the steam against the valve, for the purpose of facilitating the further lifting of the valve when once opened; but he adds, what it is important to notice, that he wishes it to be understood that he lays no claim to such recoil action, nor to the extension of the valve laterally beyond its seat.

Prior to that, a safety-valve of substantially the same mode of operation had been patented in the same country to Samuel Beyer, and the reasonable presumption is that the disclaimer was inserted in the patent subsequently granted, because it had been previously invented by another.

Letters-patent to Charles Beyer were sealed Oct. 16, 1863; and the patentee states that his invention consists in forming a flange round the valve, commencing at the outer edge of the valve-facing, which flange is under-cut and concave in shape, and that the concave side is towards the seating of the valve, which has also a flange upon it, commencing at the outer edge of the valve-seating, but that the upper surface of the flange is convex, and corresponds nearly to the concave surface of the flange upon the valve. There is a slight space between the concave and convex surfaces of the two flanges, which diminishes towards the outer edge of the same. When the steam begins to escape from between the surfaces of the valve, it gets

between the concave and convex surfaces of the two flanges, and thus acts upon a larger area, and reacts upon the concave surface of the valve, and causes it to open to a greater extent than the ordinary safety-valve. Such a valve, the patentee states, will lift promptly when the required pressure is obtained, and will open to a much greater extent than the valve in common use prior to that invention. Extra pressure upon the valve will readily close it after it has lifted, but it does not shut self-acting till the pressure in the boiler has diminished several pounds below the pressure at which the valve was lifted.

Without more, these suggestions are sufficient to show that the Beyer patent, which antedates the invention of the complainant, contains substantially the same mode of operation to produce the recoil action of the steam as that disclaimed in the English patent, and shows that the disclaimer was in all probability made because it was well known to the patentee and to the officials who issued the letters-patent that another was the original and first inventor of the patented valve. Nothing of the kind is embraced in the claims of the English patent granted to the patentee, nor is there any thing in the specification which has any tendency to show that the patentee ever supposed that he invented that feature of the improved valve which he disclaimed.

Two patents for the improvement have been granted in this country, one, the original, to the alleged inventor, and the reissued patent to the complainant, on which the suit is founded. Neither of them contains any disclaimer of the kind mentioned in the English patent, though it is conceded that both the original and the reissued patent were granted for the same invention as the English patent. Nor could that concession properly be withheld, as it is as certain as truth that the feature of the steam-valve in question was fully and clearly described in that specification, and that the patentee stated that he wished it to be understood that he did not lay any claim to the recoil action, nor to the extension of the valve laterally beyond its seat.

Explicit as that disclaimer is, still it is assigned for error by the complainant that the circuit judge erred in giving weight