“The combustion-chamber is composed of the bottom plate, a, provided with apertures, from which extend the flues, f, f, f, which are mounted on said bottom plate and held in place by flanges, a', a', on the plate and embracing the bases of the flues, as shown in Fig. 2 of the drawing. Upon the bottom plate is seated the shell, e, which is likewise held in place by a circumferential flange a' on said plate. The flues, f, f, are formed with the shoulders, f', a short distance from the upper ends thereof, and upon said shoulders rests the crown-sheet, g, which is also provided with openings, through which the upper ends of the flues, f, f, protrude. Said flues extend above the crown-sheet and terminate within the dome, D, and the shell, e, also extends above the crownsheet, and thereby forms upon the top of the combustion-chamber a bed, b, for sand, which serves to pack all the joints on the crown-sheet. The bottom plate, a, and crown-sheet, g, are tied to the air-flues, f, f, by means of rods, 1, which extend longitudinally through the interior of the air-flues and pass with their lower ends throngh ears, j, on the bottom plate and are provided with nuts under said ears, as shown in Fig. 2 of the drawings. The upper ends of the rods are bent outward and made to bear on the crown-sheet. Said rods are thus protected from soot and rust and obviate obstructions in cleaning the interior of the combustion-chamber." A careful consideration of the prior art discloses nothing which negatives the novelty of the device so described and claimed. It is true that the different elements of it are not new. There is no novelty for instance in a combustion-chamber made up of top and bottom plates, with an encasing shell or jacket, and vertical flues with apertures above and below, extending through it. This is to be found in the Winchester (1869), the Bonnell (1871), the Guettermann (1877), the Godley (1886), and the earlier Kelsey (1889) furnaces, in the last three of which also the flues are held in place by flanges on the bottom plate over which they fit; while in the Guettermann, the Jaques (1878), the Godley, and the Kelsey the flues are provided with shoulders to support the top plate, these shoulders in the Jaques and the Kelsey being external and the fues protruding up through the top plate. In the Jaques, also, the space between the raised edge of the top plate and the projecting ends of the flues is utilized as a bed to be packed with sand or cement so as to make gas-tight joints, a feature, which so far as it enters into the case in hand, is thus not new. Neither is there anything novel in tie-rods, fastening together upper and lower plates; which are shown in the Bryent (1847), the Tillman (1872), the Hemmich (1875), the Boynton (1876), the Guettermann, the Godley, and the Heim (1888). In all of these, moreover, they are located in hot ( air flues, or away from the space given up to fire and smoke, and in the Tillman, also, the advantage of having them so removed and protected against the action of the products of combustion is expressly claimed. It may be that the Tillman is a somewhat different type of furnace or heater, but tie-rods are tie-rods, wherever they are, and the novelty of locating them away from the reach of fire and smoke cannot be maintained upon any such supposed distinction. As already intimated, however, in none of the devices mentioned is a direct anticipation of the present combination to be found. None has all its features, and in none are those, which are made use of, of exactly the same character or put together in just the same way. The most that can be said is that there is a similarity of type; but it does not go far. It is said that no inventive advance is shown, and it must . be confessed that it is not large. But the Patent Office, whether the Tillman patent was before it or not, has put the seal of its approval upon the invention, and it is not to be lightly set aside. The defendants also, prompted as it is charged by a former employé, instead of devising something for themselves, or taking up with one of the other many forms open to them, have been so attracted by the complainants' heater as to appropriate all its essential features, which they have copied slavishly, even to the name—“warm-air generator”—under which it is sold. Affirming as they thus do, in the most pronounced way possible, to its superior merits and their own inability to do better, they cannot well complain if the inventive originality which is claimed for it is held to sufficiently appear. Nor is the question of infringement doubtful. As just stated, except in one small particular, the heater which the defendants were putting out at the time the bill was filed was a complete copy of that of the complainants. Since then a slight change has been made, the rods which tie together the top and bottom plates, against the ends of the flues, instead of being integral, and extending the full length of the flues, are divided up, and two short bolts substituted, which tie to lugs at either end. But the mere splitting up or multiplying of parts, the function remaining the same, does not escape infringement, and that is the case here. The rods still serve as effectively as ever to draw the top and bottom plates against the ends of the flues, tying the structure firmly together which is the point in view; and they are still located within the air flues as before, being thereby protected against soot and rust and leaving the conbustion-chamber unobstructed for cleaning. The equivalence of the two constructions is so complete and the attempted evasion so manifest that it would be a reflection upon ordinary intelligence to have it succeed. But another distinction is sought to be made. Both in the form of heater just considered, as well as the one which the defendants were apprehended in making at the time of filing the bill, the upper ends of the flues are provided with interior shoulders for the crown plate to rest upon, the same as in the Guettermann furnace, not to say others; while in the complainants' heater they are on the outside, the ends of the flues protruding above them, and affording opportunity for a cement or sand pack, to tighten the joints, as in the Jaques. But, so far as the claim in suit is concerned, the sand pack is an extraneous incident, which being specially provided for in the fourth claim is not to be implied here. Boyer v. Keller Tool Co., 127 Fed. 130, 62 C. C. A. 244. It is said, however, that the inventor has expressly declared for an exterior shoulder by the reference letter by which it is designated in the claim. The Aues are not described, as it is pointed out, as provided generally with shoulders on which the crown sheet is to rest, which would permit of either kind; but as being formed “with the shoulder, f,” the drawings of the patent, as well as the specifications where this reference is explained, being thus written into the claim. But the use of a reference letter in this way does not necessarily limit the inventor to the exact form or configuration of parts which is thus portrayed and described, without regard to possible equivalents thereto. It may, or it may not, according to circumstances, as the authorities abundantly show. Reed v. Chase (C. C.) 25 Fed. 94; Delemater v. Heath, 58 Fed. 414, 7 C. C. A. 279; Campbell Printing Press v. Marden (C. C.) 64 Fed. 782; McCormick Harvesting Machine Co. v. Aultman, 69 Fed. 371, 393, 16 C. C. A. 259; Muller v. Tool Co., yang Fed. 621, 23 C. C. A. 357; Sprinkler Co. v. Koehler, 82 Fed. 428, 431, 27 C. C. A. 200; Ross Mfg. Co. v. Randall, 104 Fed. 355, 43 C. C. A. 578; National Brake Beam Co. v. Interchangeable Brake Beam Co., 106 Fed. 715, 45 C. C. A. 544. Nor are the cases which are sometimes cited to the contrary (Weir v. Morden, 125 U. S. 98, 8 Sup. Ct. 869, 31 L. Ed. 645; Hendy v. Miners’ Iron Works, 127 U. S. 370;. 8 Sup. Ct. 1275, 32 L. Ed. 207; Lehigh Valley R. R. v. Kearney, 158 U. S. 461, 469, 5 Sup. Ct. 871, 39 L. Ed. 1055), to be differently understood. It is after all a matter of construction, in which, while a reference by letters to the drawings and specifications may be regarded , as a rule, as involving a greater particularity of description than without, the real scope of the invention is nevertheless to be considered and given due weight. No doubt there are cases where, by reason of the limitations imposed by the prior art, it is necessary, in order to distinguish and save the invention, to confine it to a certain form or arrangement of parts, which the use of reference letters may effectively serve to do. But where no such necessity exists, the patent is to be taken as a whole, and effect given to the invention as it is there disclosed and claimed, in which the reference to the drawings merely goes in with the rest. In the present instance, outside of allowing the ends of the flues to protrude above the crown plate so as to provide a bed for the cement or sand pack-which, as already stated, is a mere incident, if, indeed, it at all enters into the form of device in suit—it is of no concern whether the shoulders are outside or inside, the invention consisting in the improved construction of the combustion-chamber and the manner of assembling its different parts. Nor is any limit in this respect imposed by the prior art. The modification from exterior to interior shoulders is one of form, pure and simple, and not of substance, serving no useful purpose, and effecting no change in results. The defendants may thereby forego the opportunity for a sand pack on top of the crown sheet, but the surrender of an incidental and unclaimed advantage in this way, the essential features of the invention being retained, will not enable them to escape. It is their own concern if they have not got all the good out of the device that they might. The case having been thus disposed of in favor of the complainants, upon the question of infringement, it is not necessary to consider the charge of unfair competition which is also made, nor whether it is consistent with the rest. Let a decree we drawn, in the usual form, sustaining the patent and finding infringement, with costs. GORMLEY & JEFFERY TIRE CO. v. PENNSYLVANIA RUBBER.CO. & . No. 5, May Term, 1905. The Jeffery patents, Nos. 454,115, 466,565, 558,956, and 523,314, each for a wheel tire, and covering improvements in pneumatic tires, construed, and held not infringed. In Equity. On final hearing. Ernest Hopkinson (Livingston Gifford, of counsel), for complainant. Christy & Christy (George H. Christy and J. C. Sturgeon, of counsel), for respondent, BUFFINGTON, Circuit Judge. This is a bill in equity, brought by the Gormley & Jeffery Tire Company against the Pennsylvania Rubber Company, charging infringement by it, in the manufacture of pneumatic rubber tires for automobiles, of four patents granted to Thomas B. Jeffery and now owned by complainant. The first patent is No. 454,115, issued July 16, 1891, for a wheel tire, claims 1, 2, 3, 4, 5, and 6 of which are alleged to be infringed. The respondent contends the patent is invalid and denies infringement. All the patents here involved antedated the automobile art and contemplated use on bicycles. In pneumatic wheels for vehicles there is an inner inflatable elastic tube. This in turn is protected against external injury and internal overinflation by a flexible outer sheath. The patents all concern the engagement of such external sheath to the tire of the vehicle. This particular one recognized the prior conjoint use of these two devices as follows: "This invention is designed to provide improved means for protecting a rubber wheel tire, and is particularly designed and adapted for an inflation-tire; that is to say, a tire having a core composed of an elastically-expansible tube, which is inflated by air or gas and distended thereby to some extent, the air or gas being under such tension that but for a restraining or inclosing sheath such core would be liable to burst." As the patentee does not specifically aver what his "improved means” or particular invention was, we turn to the description of his device for light in that regard. Now a study of such description and the claims based thereon satisfies us that the improvement which Jeffery disclosed was a double or intermeshing hook connection of sheath and tire edges. Thus he says, “The rim, A, is provided with hooked edges, a', a'," and the figure referred to shows hooks on the rim, doubled back, U-shaped, on the tire, so as to form recesses and permit engagement in such recesses of corresponding hook point on the hooks of the sheath. For these provision is made: “The tire-sheath, C, is provided with correspondingly hooked edges, C', C'.” In the specification alone the word "hook," or "hooked,” is found some 17 times, and other than double-hooked connection no other method is stated or suggested. If the patentee or his device contemplated the use of any other means or form of engagement, he did not disclose it to the public. The only variation suggested was the minor detail of making the hooks bend in or out. "On some accounts," says the patentee, "the hooks on the rim are preferably turned outward, chiefly because the center of the body or inflatable core, B, is thereby rendered free from the irregularity which the hooks form when they are turned inward. On the other hand, the liability of the sheath-hooks to be pulled out from the rim-hooks by the expansive tendency of the core when inflated is somewhat less when the hooks are turned inward; but practically the two methods are about equally desirable. In either case it should be observed that the hook is open toward the axis, and it is preferably approximately in the direction of a tangent to the inflatable core, so that the expansible tendency of the core will tend to draw the hooks into close engagement." This combination of sheath and tire in the various modifications of this double-hook engagement constitutes the claims in question and the hooks on both, in some form, are elements of every claim, of which the first, for brevity's sake, will serve to illustrate, viz.: “In combination with the rim having recesses open toward the axis of the wheel, the tire sheath having its edges reversed and engaged in such recesses, and the elastic expansible core between the rim and sheath, substantially as set forth." Now, in the light of this specification, we are clear the respondent's tire does not infringe. The respondent uses other means to hold its tire in place, and its method is not disclosed or suggested in the patent in suit. If the disclosure of that patent comprised all the instruction the tire maker of to-day possessed, it is evident the art would not teach the method followed by both respondent and complainant in the manufacture of a modern automobile tire. The patentee showed a hook pure and simple. His hook was such that the hooked edges of the rim “may be turned inward or outward.” His are genuine hooks, so shaped that, by virtue of the form and use of their recesses, increase of disruptive force, whether the hook or the rim is bent outward or inward, lessens the possibility of detachment of the interlocked edges. On the other hand, if the edge of respondent's rim is turned outward, no pneumatic connection can be made with a sheath, showing that the connections used in the two methods are essentially different. Respondent's device has no hook open towards the axis, nor one in the direction of a tangent to the inflatable core. While air pressure increases the adhesion of its engaging surfaces, yet its method of doing it is not the process of increasing engagement by the catch ends of the patentee's hooks mutually interlocked in holding recesses. In our judgment it would be a miscarriage of the patent system to so construe this Jeffrey patent with its specific form of hook connection as to make it cover respondent's device, which is so different from the hook of the patent that even the complainant who owns that patent uses the same method, and not the hooked engagement of the patent. Indeed, to so construe it would be to retard, not to stimulate, inventive advance. The second patent is No. 558,956, issued April 28, 1896, for a wheel tire, claims 5 and 10 of which are alleged to be infringed. Respondent defends on the ground of noninfringement. We are of opinion the defense is sustained. The subject-matter of this patent, its late date in the art, and the close differentiations required to obtain the narrowly |