The only features of the patented combination which require attention on account of the claim of novelty are: (1) The mortising of the timbers of the supporting framework; (2) the use of wooden wedges between the ends of the transverse binders and the horizontal rails bolted to the shell of the barrel; (3) the floor of perforated lead; and (4) the filtering medium of lead in sheeted form open to the filtering passage of liquid. Aside from these matters there is no substantial controversy requiring consideration. In all other material respects the arrangement and elements of the filter were old in the art. The defenses which need be considered were prior use and description in printed publications and lack of invention. The mortising of the timbers and the use of the wedges was to give rigidity and stability to the framework. It was found in practice that the underlying segments would become bunched together during the revolution of the barrel, thereby tending to cause a collapse of the structure, and that sometimes the framework would break up, because not properly tightened at the top. There was evidence, however, that prior to Sloan's invention wedges had been used for the same purpose, and also to some extent a mortising of the timbers. Prior to Sloan's invention the arrangement most generally employed as a floor for the filtering medium consisted of hardwood boards laid upon the segments, the upper sides of the boards being corrugated and perforated; and the filtering medium laid thereon was generally asbestos cloth held down by the wooden racks, and those in turn by transverse binders, the ends of which, being beveled, were driven under the horizontal rails at the sides of the barrel. In this way the ends of the binders acted as wedges.

There was an earnest contention, supported by substantial testimony, that Sloan had nothing more to do with devising the arrangement of the framework of the filter than to follow the suggestions of his superiors, who superintended and directed the construction during the time he says he conceived his invention; but this feature of the case need not be considered. The use of lead and knowledge of its value in the chlorination process was old. For many years prior to Sloan's invention it had been used for lining chlorine barrels and other receptacles. Sloan's application was filed November 7, 1896, and his patent was dated August 10, 1897. In 1890 and continuously thereafter lead was in general use for lining barrel filters and protecting the exposed portions of iron bolts and rods in the interior. Indeed, it may be said to have been exclusively used for those purposes. Prior to Sloan's invention it had also been used as a coating, by being burned on perforated sheet-steel plates used as the supporting floors of barrel filters and upon iron grating used as holding-down racks. Perforated sheets of lead had been placed upon corrugated and perforated hardwood planks, also used as floors in barrel filters. Perforated sheets of lead had been placed over asbestos cloth as a filtering and retarding medium. As a filtering medium lead had been used in the form of a composite lead wire and asbestos cloth, and also alone in sheeted form with slotted apertures, instead of perforations. Sheets of lead had also been used for floor purposes by Sloan himself more than two years before the date of his application, though not advantageously, because they were not of sufficient weight. Years before lead had been used as a filtering medium in a stationary tank in Canada. An iron grating, covered with lead and used as a floor, was described in the publication "Metallurgy of Gold," published in London in 1894; but it was not durable, because of imperfections in the lead coating. Perforated lead, covered with asbestos, was used as a separating medium between the generating and chlorinating chambers in the Sutton patent, No. 527,899, dated October 23, 1894; and its use in other ways, though perhaps not so pertinent to this case, was described in other patents for improvements in filters.

Leonard E. Curtis and K. R. Babbitt (Rufus C. Thayer, on the brief), for appellant.

C. S. Thomas and Alfred J. O'Brien (A. T. Gunnell, H. N. Hawkins, J. A. Chinn, W. H. Bryant, H. H. Lee, and Ed. F. Richardson, on the brief), for appellee.

Before SANBORN and HOOK, Circuit Judges, and LOCHREN, District Judge.

HOOK, Circuit Judge, after stating the case as above, delivered the opinion of the court.

The result of the application of the common skill and experience of a mechanic, which comes from the habitual and intelligent practice of his calling, to the correction of some slight defect in a machine or combination, or to a new arrangement or grouping of its parts, tending to make it more effective for the accomplishment of the object for which it was designed, not involving a substantial discovery, nor constituting an addition to our knowledge of the art, is not within the protection of the patent laws. Gates Iron Works v. Fraser, 153 U. S. 332, 14 Sup. Ct. 883, 38 L. Ed. 734; Florsheim v. Schilling, 137 U. S. 64, 11 Sup. Ct. 20, 34 L. Ed. 574; Hollister v. Benedict Mfg. Co., 113 U. S. 59, 5 Sup. Ct. 717, 28 L. Ed. 901: Atlantic Works v. Brady, 107 U. S. 192, 2 Sup. Ct. 225, 27 L. Ed. 438; Dunbar v. Meyers, 94 U. S. 187, 24 L. Ed. 34; Hotchkiss v. Greenwood, 11 How. 267, 13 L. Ed. 683; Adams Electric Ry. Co. v. Lindell Ry. Co., 77 Fed. 432, 23 C. C. A. 223; Tiemann v. Kraatz, 85 Fed. 437, 29 C. C. A. 257.

The mere use of known equivalents for some of the elements of prior structures; the substitution for one material of another known to possess the same qualities, though not to the same degree; the mere carrying forward or more extended application of the original idea, involving a change only in form, proportions, or degree, and resulting in the doing of the same work in the same way and by substantially the same means-is not patentable, even though better results are secured; and this is the case, although what preceded rests alone in public knowledge and use, and not upon patent. Market Street Cable Ry. Co. v. Rowley, 155 U. S. 621, 15 Sup. Ct. 224, 39 L. Ed. 284; Wright v. Yuengling, 155 U. S. 47, 15 Sup. Ct. 1, 39 L. Ed. 64; Adams v. Stamping Co., 141 U. S. 539, 12 Sup. Ct. 66, 35 L. Ed. 849; Burt v. Eyory, 133 U. S. 349, 10 Sup. Ct. 394, 33 L. Ed. 647; Brown v. District of Columbia, 130 U. S. 87, 9 Sup. Ct. 437, 32 L. Ed. 863; Crouch v. Roemer, 103 U. S. 797, 26 L. Ed. 426; Roberts v. Ryer, 91 U. S. 150, 23 L. Ed. 267; Smith v. Nichols, 21 Wall. 115, 22 L. Ed. 566; Hicks v. Kelsey, 18 Wall. 670, 21 L. Ed. 852; National Hollow Brake-Beam Co. v. Interchangeable, etc., Co., 106 Fed. 693, 45 C. C. A. 544; National Folding Box & Paper Co. v. Lithographic Co., 81 Fed. 395, 26 C. C. A. 448.

The doctrine of equivalents applies to patents for a combination, although the measure of its effect in the particular case depends upon the position of the patent in the art to which it relates. National Hollow Brake-Beam Co. v. Interchangeable, etc., Co., supra.

The mortising of timbers to prevent them from shifting and sliding, and thereby to secure rigidity and stability of the framework, and the use of wooden wedges for a similar purpose, was nothing more than would naturally occur to any carpenter who understood his business. Mortising and the use of wedges are as old as carpentry itself; and, when the contemplated use of the structure precluded the employment of nails or other metallic fastenings, the method adopted by Sloan was but a simple and obvious expedient. It was not invention.

In the use of sheets of perforated lead as a flooring and as a filtering medium in a barrel filter there was on the part of Sloan neither discovery nor such ingenuity of adaptation as entitled him to a patent. No new function was performed by those elements of his filter, acting either singly or in co-operation with the others; nor was there a new method of performing an old one. The use of lead, and its especial value in the interior of barrel filters, were old in the art. In the floor of Sloan's filter the perforated sheets of lead performed in the same way the precise function theretofore performed by the lead-covered steel sheets, and by the perforated hardwood boards, either with or without the superimposed lead sheets; and as a filtering medium their precise function was theretofore performed by asbestos cloth, slotted sheet lead, and woven lead in combination with asbestos. They were, respectively, substitutes for each other, being well known to possess like qualities and to operate in the same way to produce the same results. The sheets of lead, in their relation to the other elements of the combination and their co-operative action, were the mere equivalents of those in prior use. There was no change of function, operation, or result. This seems to have been recognized, in part at least, by Sloan himself. He says in his specifications:

"A woven lead fabric is believed to be a novel filtering medium in this connection, and, while the best results will accrue from its use, the asbestos cloth is a valuable substitute therefor; but quite desirable results will accrue from the use of properly perforated sheet lead.".

In fact, Sloan never used a woven lead fabric as a filtering medium, but in practice confined himself to the perforated sheets, while the use of asbestos cloth was common and extensive before he had any knowledge whatever of barrel filters.

In the briefs of both parties it is said that the real operation of the sheeted lead filtering medium was to support the coarser particles of ore above it, and to cause them to act as the true filtering medium. In other words, the pulp resting upon the diaphragm was the real filtering medium, and the operation of the perforated lead was merely to retard or prevent its passage during the process of filtration. If this view be correct, and there is support for it in the testimony, it would occur to any one that the office of a retarding medium could clearly be as well performed by any durable material susceptible of stable perforation and capable of resistance to the action of chlorine gas.

Were we to exclude from consideration the lead-covered steel plates, the slotted sheets of lead, and the woven lead in combination with asbestos, upon the ground, as claimed, that they were experiments and had been discarded for better devices, there would still remain the flooring of corrugated and perforated hardwood, with and without the cover of lead sheets, and the filtering medium of asbestos, both in combination with perforated sheets of lead and without it, all of which appear in the prior art, and to have been operated successfully before Sloan's invention. We would, therefore, be brought to no different conclusion.

The decree of the Circuit Court is affirmed.

STANDARD ELEVATOR INTERLOCK CO. v. RAMSAY et al.

(Circuit Court, E. D. Pennsylvania. June 28, 1905.)

No. 22.

PATENTS-PRIOR USE-LOCKING DEVICE FOR ELEVATORS.

The Muckle & Teamer patent, No. 555,825, for a locking device for passenger elevators, claims 1 and 2, are void, being so broad as to include a device previously in use by others, and on which that of the patent is an improvement.

In Equity. On final hearing.

See 130 Fed. 151.

Howson & Howson, for complainant.

Horace Pettit, for respondent.

J. B. MCPHERSON, District Judge. This suit charges the defendants with infringing the first and second claims of letters patent No. 555,825, which were issued to John S. Muckle and William H. B. Teamer in March, 1896, and are now the property of the complainant. The end sought to be attained is thus stated in the specifi

cation:

"The object of our invention is to prevent accidents on passenger-elevators due to the carelessness of the operator in starting the car while the door is open after the car has passed the floor. This object we attain by positively locking the car on the opening of the door, and locking the door on the movement of the mechanism to start the car."

The claims are as follows:

"(1) The combination of an elevator-car, the motor controlling mechanism, a movable well-door at the landing, a latch adapted to lock the door in the closed position, with mechanism on the car adapted to release the door from the latch when the mechanism is operated to stop the car so that the door can be opened, and connections on the car between the last-named mechanism and said motor controlling mechanism, substantially as described.

"(2) The combination of an elevator-car, motor controlling mechanism, a sliding door, a latch adapted to engage with the door when closed, a device secured to the wall of the elevator-well, mechanism on the car connected to the motor-controlling mechanism, said nechanism operating to release the door from the latch, and in turn to be locked by the device secured to the wall of the elevator-well so as to prevent the car from moving when the door is opened, the said device being held clear of the mechanism on the car by the door when it is closed, substantially as described.”

The case has come into my hands at a time of the year when I cannot possibly give it the detailed discussion to which the careful and elaborate briefs of counsel are an invitation. I must content myself, therefore, with merely deciding the case, in order that there may be ample time for review, if this should be desired, and a final decision, at the next term of the Court of Appeals. In my opinion, the claims sued upon cannot be sustained, in view of the prior use at the Bingham House, in the city of Philadelphia, during a part of the year 1895, of a device that accomplished the same result. The testimony upon this subject seems to me to be clear and satisfactory, meeting the stringent requirements of the law, and I accept it as establishing the defendants' position on this branch of the de

fense. The patentees knew of this device, and their own invention was an improvement thereon, which is amply protected by the more specific claims of the patent; but the first and second claims are too broad, as I think, and cannot be construed so narrowly as to save them.

A decree may be entered dismissing the bill at the costs of the complainant.

BOSTON PNEUMATIC POWER CO. v. EUREKA PATENTS CO. et al.

(Circuit Court, D. Massachusetts. July 6, 1905.)

No. 2,022.

PATENTS-INTERFERENCE-SUIT FOR ANNULMENT.

Rev. St. § 4918 [U. S. Comp. St. 1901, p. 3394], providing for suits to annul interfering patents, gives the court jurisdiction only to adjudicate between patents, the claims of which are substantially identical, and, where such identity is not shown, it cannot declare a later patent invalid for want of patentability.

In Equity. Suit to annul patent.

Chas. F. A. Smith and Aldrich & Shurtleff, for complainant.
George N. Goddard, for defendants.

LOWELL, Circuit Judge. This was a bill in equity, brought under Rev. St. § 4918 [U. S. Comp. St. 1901, p. 3394], to annul claims 1, 2, 3, and 4 of letters patent No. 710,291, issued to Moran, as being in interference with claim 1 of Letters patent No. 673,922, to Nolan. The claims are as follows:

Nolan: "(1) In a pumping system for beer or other liquids, a plurality of barrels or receptacles, a source of pneumatic pressure, a main-pressure pipe leading from said source and communicating with all the receptacles in use, an outlet-pipe leading from each receptacle, a supplemental-pressure pipe leading from said source and communicating with each of said outlet-pipes, and a check-valve to control each of such points of communication, whereby the contents of the several receptacles are prevented from entering the supplemental-pressure pipe, substantially as described."

Moran: "(1) In a dispensing apparatus for liquids, a receptacle containing the liquid, a source of pneumatic pressure, a main pressure-pipe from said source of pressure, communicating with said receptacle above the liquid therein, a discharge-pipe from said receptacle, a discharge-faucet on said discharge-pipe, a supplemental pressure-pipe under uniform pressure with that in the main pressure-pipe, said supplemental pressure-pipe located in part above the discharge-pipe, near the discharge-faucet thereon and connected to the discharge-pipe at that place from above said discharge-pipe, and a stopcock above the discharge-pipe and within the supplemental pipe near its connection with the discharge-pipe, whereby the liquid in the discharge-pipe may be allowed to return by gravity to said receptacle by the operating of said stopcock and the liquid be prevented from leaking into the supplemental pressure-pipe from the discharge-pipe.

"(2) In a dispensing apparatus for liquids, a receptacle containing the liquid, a source of pneumatic pressure, a main pressure-pipe from said source of pressure communicating with said receptacle above the liquid therein, a discharge-pipe from said receptacle, a discharge-faucet on said dischargepipe, a supplemental pressure-pipe under uniform pressure at all times with that in the main pressure-pipe, said supplemental pressure-pipe located in part above the discharge-pipe near the discharge-faucet thereon and connected