Opinion of the Court. solved by Richardson, and never before. His patent of 1869 describes the arrangement and operation of the whole apparatus, with the adjustable ring, thus: When the pressure of the steam lifts the valve, the steam acts against the surface of an annular space between the bevel of the valve-seat and the downward-projecting flange of the cap-plate, to assist in holding up the valve against the increasing resistance of the spring. The aperture between the valve and its seat is always greater than that between the flange and the upward-projecting rim, and thus the steam in the annular space assists in holding up the valve till the boiler pressure falls below that at which the valve opened. The difference between the closing pressure and the opening pressure depends on the distance between the flange and the rim. There is a central aperture in the cap, through which the steam escapes when the valve is lifted, which is surrounded by a projecting cylindrical flange, threaded on the outside, to which is fitted a threaded ring, which can be turned up or down and secured by a set-screw. By this means, the area of the aperture for the escape of steam beyond the valve-seat is adjustable, the space being largest when the ring is down, and smallest when the ring is up." The opinion then considers the prior patents of Ritchie, Webster and Hartley, and holds that they did not anticipate Richardson's invention of 1866. In regard to the Webster patent, it says: "The Webster patent shows a huddling chamber and a stricture. But the evidence shows that valves made with the proportions shown in the drawing of Webster work with so large a loss of boiler pressure, before closing, as to be practically and economically worthless. Webster's patent describes a means of making the area for the escape of steam adjustable, consisting in adjusting up and down, on a smooth valve-stem, a sliding collar or flange, and fixing it in place by a set-screw. But it does not show the screw-ring of Richardson, with its minute delicacy of adjustment and action." Further it says: "Richardson is, therefore, entitled to cover, by the claim of his patent of 1866, under the language, a safety-valve with the circular or annular flange or.lip c c, constructed in the manner, or substantially in the manner, shown, Opinion of the Court. so as to operate as and for the purpose herein described,' a valve in which are combined an initial area, an additional area, a huddling chamber beneath the additional area, and a strictured orifice leading from the huddling chamber to the open air, the orifice being proportioned to the strength of the spring, as directed. The direction given in the patent is, that the flange or lip is to be separated from the yalve-seat by about 4th of an inch for an ordinary spring, with less space for a strong spring, and more space for a weak spring, to regulate the escape of the steam, as required." "The Richardson patents have a disc valve, an annular huddling chamber, an annular stricture at the outer extremity of the radii from the centre of the valve, an additional area which is radially beyond the disc valve, and a cylindrical steam way. But, before 1866, an annular form of safety-valve was well known. Such a valve necessarily requires an annular steam way. In the defendant's valve, complainant's Exhibit A, the same effects, in operation, are produced as in the Richardson valve, by the means described in Richardson's claims. In both structures the valve is held to its seat by a spring, so compressed as to keep the valve there until the pressure inside of the boiler is sufficient to move the valve against the pressure of the spring, so that the steam escapes through the ground joint into a chamber covered by an extension of the valve, in which chamber the steam acts expansively against the extended surface, and increases the pressure in opposition to the increasing pressure of the spring, and assists in opening the valve. wider; this chamber, in the defendant's valve, has, at its ter mination, substantially the same construction as Richardson's valve, namely, a stricture which causes the steam to act, by expansive force, against the extended surface of the valve; and in both valves, after the pressure of the steam has been somewhat reduced in the boiler, the closing movement is quickened, as the valve nears its seat, in consequence of the reduced pressure of the steam on the extended surface, and the valve comes suddenly to its seat. In the Richardson valve, the valve proper is a disc, and the extended surface is an annulus surrounding the disc, while, in the defendant's Opinion of the Court. valve, the valve proper is an annulus, and the extended surface. is a disc inside of the annulus. But this is a mere interchange of form between the valve proper and the extended surface,' within the skill of an ordinary mechanic." It is contended by the defendant that the proof shows that a valve made in the required proportions of the patent of 1866 and in accordance with its drawing and description, without the improvement of 1869, and with the area of escape at the outlet smaller than the area of entrance at the ground joint, is not as economical or as good in action as the earlier Webster valve; that a valve constructed in accordance with the patent of 1866 is not an economical valve, but operates with a large loss of steam; that the valves sold by the plaintiff as Richardson valves, being the same in pattern as those sold by it since it began business, are not constructed so that the area of escape from the huddling chamber is smaller than the area of entrance from the ground joint, but on the contrary, it is about twice as large; and that the plaintiff has never put a valve on the market with the orifice of escape from the huddling chamber smaller than the orifice of entrance into that chamber. We see no reason, in the record, for disturbing the conclusions of the master and the Circuit Court, that the entire commercial value of the valves made and sold by the defendant was due to the improvement covered by the patent of 1866, and that the plaintiff's valves of commerce all of them contain the improvements covered by the patent of 1866. Moreover, the master reports profits only, and finds that the plaintiff has suffered no damages in addition to the profits to be assessed against the defendant. If there had been an award of damages, and the loss of trade by the plaintiff, in consequence of the competition by the defendant, had been an element entering into those damages, it would have been a material fact to be shown by the plaintiff that it was putting on the market goods embodying the Richardson invention; but, as the plaintiff recovers only the profits made by the defendant in using in its business the Richardson invention, it is immaterial whether or not the plaintiff itself employed that invention. The Opinion of the Court. profits made by the defendant cannot be increased or diminished by any act on the part of the plaintiff; and the amount of them is not affected by the question whether during the same time the plaintiff did or did not use the patented invention. In regard to the holding by the master and the court that all the profits of the defendant from the valves it made and sold were to be attributed to the employment by it of the improvement covered by the patent of 1866, we hold that, in view of what was determined in the former opinion of this court, and on the whole case, the safety-valves known to the art and open to be used by the defendant would not do the same work as the Richardson invention covered by the patent of 1866, or have any commercial value; and that, within the case of Garretson v. Clark, 111 U. S. 120, it appears, by reliable and satisfactory evidence, that the profits made by the defendant are to be calculated in reference to the entire valve made and sold by it, for the reason that the entire value of that valve, as a marketable article, is properly and legally attributable to the patented feature of the patent of 1866. As to the assignment of error that the master did not ascertain what part of the profits derived by the defendant was due to the patented improvements covered by the two patents to Crosby, the master said, in his report, as before quoted: "The defendants claim that some of the profits which they have made are due to the peculiar form of their valves, but the form which they used in making their valves, was the form in which they clothed the Richardson invention, the life of their valves, and without that life the Crosby form is worthless." The defendant contends, that the master ought to have found, upon the evidence, that, with the exception of an allowance of a nominal sum for profits on account of the Richardson invention, the profits of the defendant accrued from its employment of the Crosby inventions. This contention was made before the master, and was overruled by him. There was some evidence before the master relating to the form of the Crosby valve, to the effect that it had an encased spring, and was readily attached and adjusted, and that those Opinion of the Court. features of its construction were advantageous. The first patent to Crosby does not show any encased spring; and while the second patent to him shows an encased spring, its claims relate solely to the features which produce and regulate the recoil action of the steam. The master was correct, therefore, in saying that the patented improvements of Crosby embodied the form in which the defendant clothed the Richardson invention, the life of the defendant's valve, and without which the Crosby form was worthless. There is no evidence that any of the things patented by Crosby gave any advantage in selling the defendant's valve. It appearing that the defendant's valve derived its entire value from the use of the Richardson invention covered by the patent of 1866, and that the entire value of the defendant's valve, as a marketable article, was properly and legally attributable to that invention of Richardson, the plaintiff is entitled to recover the entire profit of the manufacture and sale of the valves. Elizabeth v. Pavement Company, 97 U. S. 126, 139; Root v. Railway Company, 105 U. S. 189, 203; Garretson v. Clark, 111 U. S. 120; Callaghan v. Myers, 128 U. S. 617, 665, 666; Hurlbut v. Schillinger, 130 U. S. 456, 471, 472. The defendant contends that the master and the Circuit Court erred in disallowing as a credit to the defendant in diminution of the profits reported, the sum of $1978.34, it being contended that that was an expense suffered by the defendant in modifying and reconstructing certain valves to render them more perfect and more salable. These were valves made by the defendant and destroyed by it before sale, or after a sale and an exchange for other valves: which destroyed valves did not appear in the account on either side, thus becoming unsold valves. The expense thus referred to is one incurred in making experimental and defective valves. In regard to this item, the master said in his report: "Item 7 is for modification and reconstruction of iron valves. The costs of the reconstructed valves have already been charged in the costs of valves for the periods in which the reconstruction, so called, took place. The old valves were destroyed and a salvage made of such parts as were of value or could be |