roll, B, which is centrally located between the two frames. On the projecting end of driving-shaft, A, I provide a driving-pulley, A', which is connected by a suitable belt with the power-shaft.

Directly above the grinding-roll, B, is mounted a pressing-roll, C, which is of much smaller diameter than the roller, B, and is mounted in the adjustable journal-boxes, d, which are suspended in recesses, d', formed in the side walls of the frame. These boxes, d, are supported in a suspended position and adjusted by means of the threaded bolt, e, which enters a threaded aperture in the upper end of each box and passes through an opening, e', formed in the top plate, f, of the frame. The lock-nuts, e2, e3, are provided above the plate, f, for supporting and adjusting the bolt, e. In each of the side frames of the machine I provide the vertical bolts, g, which support on their upper ends a crossbar, G. the said bolts, g, carrying jam-nuts for supporting and locking the crossbar. In the center of the said crossbar I provide a threaded opening adapted for the reception of the screw, h, which is provided with a shouldered lower end which fits into an aperture provided in the spring, H. The spring, H, is bowed, as illustrated, and bears at each end upon the journal-boxes, d, of the presser-roll, C, for the purpose of keeping the said presser-roll in constant contact with the grinding roll, or, in other words, for the purpose of

keeping the quill during the operation of the machine in close contact with the grinding-roll, while at the same time allowing the said presser-roll to yield upwardly. Each end of the spring, H, is provided with an elongated opening through which the bolts, e, pass. The tension of the spring, H, may be increased or diminished by adjusting the screw, h, carried by the bar, G.

*

In the operation of my machine the feathers are guided by the operator between the feed-rolls, J, K, which are driven rather slowly by means of the driving-pulley, T, carried by the shaft of the upper roller, J. This operation crimps or crushes the thick quill of the feather as it passes between the corrugated rolls and feeds the said quill between the grinding-roll, B, and the yieldingly-mounted presser-roll, C, the said presser roll tending to keep the

quill in close contact with the grinding-roll, which revolves very rapidly and grinds off the underside of the quill, removing everything, including the pith, with the exception of the bone which carries the web or vane of the feather." Two claims are set forth in the patent, with the first of which only we have to do. It is as follows:

"(1) In a quill-grinding machine, the combination with the supporting frame, of a grinding-roll journaled in said frame, a presser-roll, C, bearings for said presser-roll suspended in the machine-frame so as to be capable of moving upwardly, means for adjusting said suspended bearings so as to regulate the distance between the presser-roll and the grinding-roll, a spring, H, adapted to bear at each end on the suspended journal-bearings, means for adjusting the tension of the said spring, and a pair of feeding and crushing rolls arranged in front of the grinding and presser rolls located so as to hold the quills while the grinding-roll is operating to remove the pithy material from the bone of the quill, substantially as described."

The validity of the patent in suit is not here in question. It was sustained by the learned judge of the court below, who, upon the first hearing, held that defendant's machine infringed the first claim of the patent. Upon a rehearing, however, the court was of opinion that defendant's machine did not infringe the patent in suit, for the reason that it did not have means for adjusting the tension of the spring referred to in claim 1, above quoted. The court below, in its opinion delivered after the rehearing, says:

"The patent claims as one of the elements in the combination, 'means for adjusting the tension of the said spring.' The specification shows that the particular means described by the inventor was the screw, h: "The tension of the spring, H, may be increased or diminished by adjusting the screw, h, carried by the bar, G.' Neither this screw nor any equivalent device is to be found in the defendant's machine, but the tension of the springs is adjusted therein by the same means that is used for regulating the distance between the two rollers, namely, by the bolts, e. The defendants have therefore omitted entirely one element of the plaintiff's combination, and accordingly cannot be held to infringe. I think this position is sound, and is supported by the following authorities: Water Meter Co. v. Desper, 101 U. S. 332 [25 L. Ed. 1024]; Wright v. Yuengling, 155 U. S. 47 [15 Sup. Ct. 1, 39 L. Ed. 64]; Pittsburg Meter Co. v. Supply Co. (C. C. A., 3d Circuit) 109 Fed. 644 [48 C. C. A. 580]. As was said in the last-cited case: 'Nothing in the law of patents is better settled than the rule that a claim for a combination is not infringed, if any one of the described or specified elements is omitted without the substitution of any equivalent thereof.'"

We agree with what the learned judge has here said, and think that the complainant below is bound by the limitations imposed by his own language, as used in the first claim of the patent in suit. As said by Mr. Justice Bradley, in delivering the opinion of the Supreme Court, in Water Meter Co. v. Desper, supra:

"It may be observed, before concluding this opinion, that the courts of this country cannot always indulge the same latitude which is exercised by English judges in determining what parts of a machine are or are not material. Our law requires the patentee to specify particularly what he claims to be new, and if he claims a combination of certain elements or parts, we cannot declare that any one of these elements is immaterial. The patentee makes them all material by the restricted form of his claim. We can only decide whether any part omitted by an alleged infringer is supplied by some other device or instrumentality which is its equivalent."

A careful consideration of the device of the patent in suit, convinces us that the element described in the combination of claim 1, to wit, "a spring, H, adapted to bear at each end on the suspended. journal bearings; means for adjusting the tension of said spring," was not only made material by its inclusion in the claim and specifications, but is in fact, a material element of the combination constituting the invention claimed. An inspection of the drawings and models. submitted to the court, makes it perfectly manifest that the plate. spring, H, the ends of which press upon the journal bearings on either side of the presser-roll in connection with the means for adjusting its pressure, furnished by the screw, h, furnishes a not unimportant part of the machine described in the patent. It must be borne in mind that the journal bearings, holding the ends of the shaft of the presser-roll, may be moved up or down by means of the bolts,

e, and the nuts, e2 and e3, as described in the specifications. This vertical movement enables the operator to regulate the distance between the presser-roll and the grinding-roll, and this regulation may be necessary by reason of the varying size of the materials to pass between the rolls. When the presser-roll has been thus raised or lowered to the distance required from the grinding-roll, it is held down, but yieldingly, by the ends of the plate spring, H. It is apparent, that if this plate spring is fixedly placed, its pressure at the ends on the journal bearings, and hence on the presser-roll, will be increased or diminished as the presser-roll is raised or lowered. It is most important, then, that there should be means for preserving just the pressure required, whether the presser-roll is raised or lowered. This can be accomplished by the means of adjustment provided in the screw, h, passing through the top bar of the frame, with its lower end resting on the middle of the arch of the plate spring, H. Thus, if the material to be treated requires that the presser-roll should be raised to a greater distance from the grinding-roll, in order to pass readily between the two, the raising of the presser-roll against the ends of the spring, H, would increase the pressure. It might, however, be desirable that the actual pressure should remain the same as before the spring is raised, and the means of adjustment supplied by the screw, h, would enable the original pressure to be maintained.

We now come to the consideration of the machine of the defendant below, alleged to infringe the patent in suit. It is admitted that the only difference between the combinations constituting the two machines, is in respect to this plate spring, H, and means for adjusting the same. By referring to the drawings of the defendant's machine, here

with reproduced, it will be seen that the journal bearings of the presserroll may be raised or lowered in the sides of the frame by threaded bolts and nuts similar to the device for that purpose, in the patent in suit, and the distance between the presser-roll and the grinding-roll may be thus increased or diminished at will. As in the patent in suit, the journal bearings are suspended by the bolts referred to, but are free to be moved upwards. There is in each side of the defendant's machine, encircling the bolt, a coiled or helical spring, which furnishes a yielding pressure upon each end of the shaft of the presser-roll. It is apparent, that when the presser-roll is raised for any purpose, the compression of these coiled springs must increase the pressure upon the roll, and so conversely, when the presser-roll is lowered, so as to decrease the distance between it and the grinding-roll, the pressure of the helical spring is decreased. It follows that, in any given required position of the presser-roll, with reference to the grinding-roll, the pressure of these springs can neither be increased nor diminished. To increase the pressure, the presser-roll must be raised, thus abandoning the required position, and conversely, to decrease the pressure, the presser-roll must be lowered, which would again abandon the required position; or, if the two rolls were already so close together that no further approach could be made, no decrease in pressure could be obtained. It is thus seen that the defendant's machine lacks the means of adjusting the pressure of the spring, mentioned in claim 1 of the patent in suit, and particularly set forth by reference to letters H and h, both in the claim and specifications.

It is true, that the function of the two ends of the flat spring, in the machine of the patent in suit, is pressure upon the ends of the shaft of