sodium which they are using, which is cryolite, and because the Hall process contemplated and called for a fusion of the double fluoride by external means of heating, whereas the defendants are using to fuse the bath the heat generated by the resistance of the bath to the elec tric current. The whole defense of infringement is based on a narrow and wholly impossible construction of the Hall patent.

As has been before stated, this patent is a pioneer patent, and its terms will be liberally construed to cover the patentee's real discovery. (Sessions v. Romadka, C. D., 1892, 382; 59 O. G., 938; 145 U. S., 29; Morley Sewing Machine Company v. Lancaster, C. D., 1889, 380; 47 O. G., 267; 129 U. S., 263, 273.) Coming now to consider the claim that the patent does not cover fused cryolite as a bath, it should first be noted that cryolite is a double fluoride of aluminium and sodium, a metal more electropositive than aluminium. It is therefore exactly within the words of both claims here in suit. But the contention is that the patentee has disclaimed any right to the exclusive use of cryolite. It is not denied that the patentee had used cryolite as a bath before he made his application; but it is said that he described its use in his first application and stated in substance that it was not so good as a different proportion of the fluorides, and then subsequently omitted reference to it as a bath altogether in his final specifications. This is said to be a disclaimer of cryolite as a bath material. Hall's description of his bath is as follows:

In the practice of my invention I prepare a bath for the solution of the alumina by fusing together in a suitable crucible, A, the fluoride of aluminium and the fluoride of a metal more electropositive than aluminium-as, for example, the fluoride of sodium, potassium, etc.-these salts being preferably mingled together in the proportions of eighty-four parts of sodium fluoride aud one hundred and sixty-nine parts of aluminium fluoride, represented by the formula Na Al F. A convenient method of forming the bath consists in adding to the mineral cryolite three hundred and thirty-eight four hundred and twenty-firsts of its weight of aluminium fluoride. The object of thus adding aluminium fluoride is to secure in the bath the proper relative proportions of the fluorides of aluminium and sodium.

And again the patentee says:

While I consider the proportions of fluorides of sodium and aluminium herein before stated as best adapted for the purpose, such proportions may be varied within certain limits without materially affecting the operation or function of the bath, as, in fact, any proportions which may be found suitable may be employed.

The patentee states first the proportions of the aluminium fluoride and sodium fluoride which he prefers for his bath. They are eighty-four parts of sodium fluoride and one hundred and sixty-nine parts of aluminium fluoride. Then he proceeds to tell a convenient way for reaching these proportions. Cryolite, as we have said, is an article of commerce. He suggests that the best bath can be made by taking cryolite and adding to it three hundred and thirty-eight four hundred and twenty-firsts of its weight in aluminium fluoride. After this, for the very object of including cryolite, which, as we know, he had used for

the purpose, and all other double fluorides of sodium and aluminium which would work, he says that the proportions may be varied. What proportions does he mean? Why, the proportions of the two fluorides, of course. The labored construction that the proportions to be varied are those of the cryolite and the aluminium fluoride is wholly unten able. How may they be varied? Within certain limits. What does that mean? The patentee goes on to state when he says

that any proportions which may be found suitable may be employed.

Cryolite is now found suitable, and the patentee had found it suitable when he made his application. Could anything be more unlikely than that Hall or his patent solicitor, after they had been successful in an interference controversy with Heroult, whose only bath was one of cryolite, would have framed his specification with the intention of not including a cryolite bath in the monopoly he was seeking? We think the patent very aptly drawn to cover the use of every double fluoride of aluminium and sodium which can be made to produce aluminium when used as a bath in the Hall process. The proportions are immaterial so long as it is a double fluoride of these metals.

Next is the defense based on the use of external heat in Hall's apparatus, as described in his patent, and defendant's use of internal heat. Hall's claims do not say what heat shall be used to fuse the bath. The process is described as beginning with a fused bath. The argument is that because Hall in his specification describes an apparatus for the fusion of the bath by external heat therefore he limits himself to a process in which external heat is used and confers upon the world at large the right to use his process if only some other mode of applying the heat is employed, and this in the face of the words of the patent

nor does this apparatus described herein with more or less particularity form any part of the invention herein.

We do not see how the patentee could have used stronger words to avoid the difficulty in which defendant wishes to involve him. Then, too, we have the refined point that the language of the claim itself excludes the possibility of electric heating, because it speaks of dissolving alumina in a fused bath of the double fluorides

and then passing an electric current by means of a carbonaceous anode through the fused mass.

This language is as applicable to electric heating as to any other. The word "then" is used to indicate that the electrolysis is to follow the solution of the alumina in the fused bath. Now, whether the current or a furnace-fire fuses the bath, the current which is passed through the fused mass to perform electrolysis is passed through after the fusion.

The decision of the Supreme Court in the case of Tilghman v. Proctor (C. D., 1881, 163; 19 O. G., 859; 102 U. S., 707) is conclusive on this 10693 PAT- -38

point. There the patent was for a process for the treatment of fats and oils in which the application of heat was one of the necessary steps. Mr. Justice Bradley, speaking for the Court,, said:

Another ground assumed by the defendants to avoid the charge of infringement is that they do not heat the mixed mass in the manner pointed out in Tilghman's specification, but, instead of heating the containing-vessel by an outside application of heat, they heat the contents by the introduction of superheated steam; but we think that this does not alter the essential character of the process. The heating by steam is clearly an equivalent method to that of heating by an external fire: The patent does not prescribe any particular method of applying the heat, except when using the pipe-and-coil apparatus described in the specification, and even in the use of this apparatus the outward application of the heat to the pipe is suggested incidentally and as a matter of convenience rather than as an essential requisite. The patentee showed one method in which the heat could be applied. That was all that was necessary for him to do. If it could be applied in any number of different methods it would not affect the validity of the patent as a patent for a process. The method of heating the mixture by the introduction of steam may be attended with some beneficial results in producing an agitation or an automatic circulation helpful to the perfection of the admixture of the water and fat, and so far it may be an improvement on heating from without. Suppose this to be so, as before said, the introduction of an improvement gives no title to the use of the primary invention upon which the improvement is based.

Finally, it is said the defendant does not infringe because the claim calls for a carbonaceous anode and the defendant uses a carbon anode. Carbonaceous means pertaining to carbon or made of carbon. It includes anodes made partly of carbon and partly of some other substance; but it certainly covers an anode made all of carbon.

A decree will be entered for the complainant finding the complainant's patent is valid and that the defendant infringes both the first and second claims thereof, and perpetually enjoining the defendant from further infringement, with the usual reference to a master to determine the damages.

[U. S. Circuit Court of Appeals-Second Circuit.] WESTINGHOUSE AIR BRAKE COMPANY v. NEW YORK AIR BRAKE COMPANY et al. WESTINGHOUSE et al. v. NEW YORK AIR BRAKE COMPANY et al.

Decided October 15, 1894.

69 O. G., 945.

1. WESTINGHOUSE, JR.-No. 376,837-FLUID-PRESSURE AUTOMATIC BRAKE MECHAN

ISM-INFRINGEMENT.

Claims 1, 2, and 3 of Patent No. 376,837, issued January 24, 1888, to George Westinghouse, Jr., for improvements in fluid-pressure automatic brake mechanism, which consists in actuating the emergency devices by a piston independent of and unconnected with the triple-valve piston and actuated by auxiliary-reservoir pressure, Held to be infringed by a device which uses two pistons, one of which is forced down by auxiliary-reservoir pressure, but does not act directly upon the emergency-valve, and claims 1 and 3, not embracing an additional-valve, as claim 2 does, are also infringed by a device in which the initially check-operat ing piston actuates the emergency-valve directly.

2. SAME-NO. 448,827-AIR-BRAKES-VOID-AS BEING FOR THE SAME INVENTION IN NO. 376,837 TO SAME PATENTER.

Claims 1 and 2 in Patent No. 448,827, issued March 24, 1891, to George Westinghouse, Jr., for improvements in air-brakes, Held to be void, on the ground that, in view of the state of the art, there was no patentable invention in their subject-matter apart from the invention shown in Patent No. 376,837, issued to the same patentee.

3. SAME-NO. 172,064-AIR-Brake Valves-Not INFRINGED.

Claim 3 in Patent No. 172,064, issued January 11, 1876, to George Westinghouse, Jr., for improvements in air-brake valves, which must include a port through the center of the piston, Held not infringed by a combination of old elements which employs a piston with a side port.

4. SAME-No. 222,803-OPERATING COCKS FOR FLUID-Pressure BrakeES—PIONEER

INVENTION-INFRINGED.

Claims 2, 3, and 4 of Patent No. 222,803, issued December 23, 1879, to George Westinghouse, Jr., for improvements in operating cocks for fluid-pressure brakes, which provides for operating both the supply and exhaust valves by a single stem, that only one can be opened at once, that either may be opened separately and both closed simultaneously and automatically, Held to cover a pioneer invention and infringed by a device which accomplishes the same result, though it is specifically different from that shown in the patent.

5. PARK-AIR-BRAKES-INFRINGED.

Claims 1 and 2 in Patent No. 393,784, issued December 4, 1888, to Harvey S. Park, for improvements in air-brakes, which include an emergency piston and valve, the latter being mechanically opened and closed by connection with the piston, Held not to be infringed by a device the piston of which does not hold the valve to its seat nor restore it to its place.

Messrs. Kerr & Curtis, Mr. George H. Christy, Mr. Frederic H. Betts, and Mr. J. Snowden Bell for the appellant.

Mr. J. E. Maynadier, Mr. Fredk. P. Fish, Mr. Esek Cowen, and Mr. Edward C. James for the appellees.

Before WALLACE, LACOMBE, and SHIPMAN, Judges.

SHIPMAN, J.:

The various appeals in these three cases are from decrees of the Circuit Court for the Southern District of New York upon three bills in equity for the alleged infringement of Letters Patent.

No. 4,977 was founded upon Letters Patent No. 376,837, dated January 24, 1888, and Letters Patent No. 172,064, dated January 11, 1876, each issued to George Westinghouse, Jr. The Circuit Court decreed that the defendants should be enjoined against their infringement of the first, second, and third claims of No. 376,837 and that the bill should be dismissed as to No. 172,064.

No. 5,315 was founded upon Letters Patent No. 448,827 to George Westinghouse, Jr., dated March 24, 1891. The Circuit Court decreed that the defendants should be enjoined against the infringement of the first and second claims of this patent.

No. 4,976 was founded upon Letters Patent No. 393,784, dated December 4, 1888, to Harvey S. Park, and No. 222,803, dated December 23, 1879, to George Westinghouse, Jr. The Circuit Court dismissed the

bill as to No. 393,784 and decreed that an injunction should issue against the infringement by the defendants of the second, third, and fourth claims of No. 222,803.

The complainants and defendants have respectively appealed from the decrees which were respectively adverse to them.

These patents are for improvements in railroad-brakes by fluid-pressure, and will be better understood if they are considered in the order of their relation to each other rather than as they are grouped in the bills in equity, and therefore Nos. 376,837 and 448,827, which was originally applied for in the application which resulted in No. 376,837, naturally take precedence.

It is necessary to give the history of the development by the patentee of the automatic "quick-action" air-brake system, because the construction of the important claims of the two patents now under consideration and of the patent to Park-No. 393,784-depends to a great degree upon a knowledge of this history, which was accurately condensed by Judge Townsend as follows:

The first practical air-brake is known as the "plain brake," and is described in Patent No. 88,929, granted to George Westinghouse, Jr., April 13, 1869.

It consisted of a pump, operated by steam from the locomotive-boiler, which compressed air into a reservoir located under the locomotive-cab, which reservoir communicated by a pipe with a cock or valve in said cab called the "engineer's valve," which was so located as to be readily manipulated by the engineer.

From this valve a pipe extended back under the tender and was connected to a similar pipe under the entire length of the first car by a flexible hose. Each of the succeeding cars had a similar pipe similarly connected. This pipe was called the "train-pipe." From the train-pipe of each car a branch pipe communicated with the forward end of a cylinder called the "brake-cylinder." This cylinder was provided with a piston, the stem of which was connected with the brake-levers on the When the engineer wished to apply the brakes, he opened the engineer's valve and the compressed air from the main reservoir flowed back through the train-pipe and branch pipes into the brake-cylinder on each car, pushing the pistons backward, causing the piston-stems to operate the brake-levers and force the brake-shoes against the wheels.

car.

When he wished to release the brakes, he so shifted the valve as to shut off the flow of compressed air from the main reservoir, and to open a port or vent leading from the train-pipe to the open air. Thereupon the compressed air in the brakecylinders escaped into the open air, the pressure of the pistons was removed, and the pistons were forced forward again by means of springs, thus moving the brake shoes away from the wheels.

The validity of this patent was sustained in Westinghouse v. Gardner & Ransom Air Brake Company, (C. D., 1876, 317; 9 O. G., 538.)

The operation of this plain brake was open to certain objections. It was too slow, and was attended by danger of collision in case one part of the train became detached from the other part.

The brake next to be considered is known as the "automatic brake," which appears to have been patented by George Westinghouse, Jr., about 1872 or 1873.

It embodied the addition of an auxiliary reservoir and a triple-valve device to each car. Each reservoir was of sufficient capacity to operate its brakes once, thus to provide for automatic action in case of accident. The triple-valve device was located at the junction of connections between pipes leading to the train-pipe,