because when it is depressed it does not pass under the lower edge of the plowshare, although it passes below the plane of that edge upon the side of it. In support of this contention, it insists that the invention of Lenhart is so limited by the prior art that, if its machine infringes, his invention is anticipated and the patent is invalid. The principle of Lenhart's invention is the regulation of the tilting of the ordinary walking plow by means of an adjustable sliding plate attached to the under side of the moldboard or share of the plow. Its mode of operation consists in the adjusting of this plate by sliding it up and down by means of the slot, the bolt, and the nut, so that the plow will run level. The patents which counsel for the appellant cites to show that this principle and mode of operation, which the appellant has clearly embodied in its sliding shoe, were disclosed before Lenhart invented his plate, are No. 226,750, to F. Simonds, April 18, 1882; No. 274,491, to W. K. Harrell, March 27, 1883; No. 397,891, to A. F. Bjorkstrom, February 19, 1889; No. 336,946, to F. Reyner, March 2, 1886; and No. 263,637, to W. J. N. Welborn, August 29, 1882. The patents to Simonds and Harrell do not describe sliding plates upon the moldboards of plows, but shoes beneath the plows, upon which they bear when in operation; and these shoes lack the essential principle of Lenhart's invention-its adjustability to the changing tendency of the plows to tilt toward the side of the moldboards. The patent to Bjorkstrom shows a plow provided with two shoes-one under the heel of the landside, and the other under the heel of the moldboard. The shoe under the heel of the moldboard consists of a small, tapered plate, pivoted at its front end to the inner side of the moldboard, with its rear end adjustable vertically by means of a slotted ear which operates upon a bolt in the moldboard of the plow. The forward end of the tapered shoe cannot be raised or depressed without removing the entire shoe from the plow. This device therefore lacks the requisite adjustability which the sliding plates of Lenhart and the appellant possess, by means of which the entire plates may be raised or depressed without detaching them from the plows. Bjorkstrom's device was not conceived or constructed to regulate the tilting of the plow toward the side of the moldboard, but to serve the same purpose that the shoe on the landside of his plow was made to serve the purpose of shoes on a sled. It was made to be what Bjorkstrom calls it-a wear-plate. When the appellant adopts the shoe of Bjorkstrom, it will not infringe the patent to Lenhart, because it will not then accomplish the purpose which his invention was made to attain, and will not avail itself of the principle which Lenhart's device involves. It may be that it is because it seeks to attain that purpose that it has neglected Bjorkstrom's pivoted shoe, and appropriated Lenhart's sliding plate. The patents to Welborn and Reyner have little relevancy to the issue in this case. The former describes a guide, and the latter a stirring attachment to a plow. Neither of the patents discloses an adjustable sliding plate for regulating the tilting of the plow, or any other equivalent means for accom. plishing that purpose. This brief review of the patents cited by counse for the appellant discloses the fact that there is nothing in them which describes or suggests the adjustable sliding plate of Lenhart; no description of any device which will accomplish the purpose of his inven

tion; nothing that places the adjustable, slotted, sliding plate of the appellant, with its blunted, flattened lower edge, beyond the limits of the grant to Lenhart, or that relieves the Lourie Company of the infringement of which the court below found it to be guilty.

But counsel for the appellant persuasively argues that his client does not infringe upon the grant to Lenhart, because the only device secured by the first and second claims of the patent to him is an adjustable plate which slides under the edge of the share to raise or lower it, and which cuts the roots beneath the turning turf, and that the sliding plate of the appellant never projects under the edge of the share, and never cuts the roots beneath the sod. This construction of the two claims of the appellee which have been quoted, however, does not commend itself to our judgment. It is too narrow, refined, and technical. It permits a nullification of the grant by a mere change of the form of the foot of the device from a sharp, turned edge, to a blunted, straight edge, while the changed machine retains the principle and the mode of operation and performs the function sought and secured by the patented device. Grants of letters patent should receive a fair interpretation-one that vitalizes rather than one that paralyzes them. If the sliding, adjustable plate of the appellant had been disclosed in the prior art, and if the only novelty or patentability of Lenhart's device consisted of the special form of its lower edge, whereby it was adapted to pass under the edge of the plowshare and to cut the roots of the grass, his patent might be limited to a slide of that specific form. Sandwich Enterprise Co. v. Joliet Mfg. Co., 33 C. C. A. 491, 493, 91 Fed. 254, 256; Campbell v. Richardson, 76 Fed. 976, 22 C. C. A. 669. This, however, was not the case. No one before Lenhart regulated the tilting of the ordinary walking plow by an adjustable sliding plate on the inner side of the moldLoard or share. He discovered the principle and the mode of operation by which he has effected this regulation. He was the original inventor of the slotted sliding plate, by means of which the desideratum he sought was first attained. The purpose of the plate and of the invention was not to cut the roots of the grass beneath the sod, but to regulate the tilting of the plow. The cutting of the roots was but an incident of the particular form of the plate which Lenhart described. But that form was not the essence of his invention, and it is neither mentioned nor claimed in either of the two claims of the patent which are here in litigation.

May the appellant escape liability for infringement because, instead of making the foot of its adjustable plate thin, and bending or turning it toward the plowshare, so that in operation it would pass under it and cut the roots of the grass, it has made it thick and blunt, and extending vertically downward below the plane of the plow seveneighths of an inch distant from, and on the side of the edge of, the plowshare? Mere changes of the form of a patented device, where the principle or mode of operation is adopted, will not avoid infringement, unless the form of the machine is the distinguishing characteristic of the invention. National Hollow Brake Beam Co. v. Interchangeable Brake Beam Co., 106 Fed. 693, 711, 45 C. C. A. 544, 562;

Kinloch Tel. Co. v. Western Electric Co., 51 C. C. A. 362, 365, 113 Fed. 652, 655. The distinguishing characteristic of this invention was not the thinness or bend of the sliding plate, but its position and adjustability upon the moldboard.

A copy of the thing described in a patent, either without variation, or with such variations as are consistent with its being in substance the same thing, is for all the purposes of the patent law the same device as that described in the patent. Burr v. Duryee, 1 Wall. 531, 573, 17 L. Ed. 650. One who claims and secures a patent for a new machine thereby necessarily claims and secures a patent for every mechanical equivalent for that device, because, within the meaning of the patent law, every mechanical equivalent of a device is the same thing as the device itself. A device which is constructed on the same principle, which has the same mode of operation, and which accomplishes the same result as another by the same means, or by equivalent mechanical means, is the same device, and a claim in a patent of one such device claims and secures the other. Machine Co. v. Murphy, 97 U. S. 120, 125, 24 L. Ed. 935. The sliding, slotted, adjustable plate of the appellant, with its thickened, flattened lower edge or foot by the side of, and seven-eighths of an inch distant from, the edge of the share of the plow, involves the same principle, has the same mode of operation, and performs the same function-the regulation of the tilting of the plow-by mechanical means equivalent to the adjustable sliding plate of Lenhart, with its thin edge bent against the plowshare so that it may slide under its edge when it is depressed below it. One may not escape infringement by adding to or subtracting from a patented device, by changing its form, or by making it more or less efficient, while he retains its principle and mode of operation, and attains its result by the use of the same or of equivalent mechanical means. Walker on Patents, §§ 347, 348; Sewall v. Jones, 91 U. S. 171, 183, 23 L. Ed. 275; Coupe v. Weatherhead (C. C.) 16 Fed. 673, 675. The decree below is affirmed.

LETSON et al. v. ALASKA PACKERS' ASS'N.

ALASKA PACKERS' ASS'N v. LETSON et al.

(Circuit Court of Appeals, Ninth Circuit. March 1, 1904.)

No. 944.

1. PATENTS-INFRINGEMENT-CAN-CAPPING MACHINE.

The Jensen patent, No. 376,804, for a can-capping machine, was not for a pioneer invention, in the sense that the machine was the very first to accomplish the heading of filled cans, yet such machine was the first to accomplish that result with any practicable degree of speed or efficacy, and the claims of the patent are entitled to a fairly liberal construction Claims 3, 5, 9, 10, and 11 held infringed by the machine of the Letson & Burpee patent; No. 629,574, and claim 1 held not infringed.

130 F.-9

3. SAME-EQUivalent DevICES.

The fact that an alleged infringing mechanical device lacks one of the functions of the patented device does not avoid infringement, where such function is not claimed in the patent.

Appeal from the Circuit Court of the United States for the Northern Division of the District of Washington.

For opinion below, see 119 Fed. 599.

These are cross-appeals from the decree of the Circuit Court for the District of Washington rendered in a suit brought by the Alaska Packers' Association, hereinafter designated the appellee, against the firm of Letson & Burpee, hereinafter designated the appellants, for infringement of letters patent No. 376,804, dated January 24, 1888, issued to Matthias Jensen, for an improvement in can-capping machines. Claims 1, 3, 5, 9, 10, and 11 were alleged to be infringed. The trial court found that claims 5, 9, and 10 were infringed, and that the other claims were not infringed. The appellee was the assignee of the patent above referred to, and extensively used and manufactured the machines covered thereby. The appellants obtained on July 25, 1899, 11 years after the issuance of the Jensen patent, a patent for a can-capping machine (patent No. 629,574), and thereunder manufactured the machines which are charged to be infringements of the Jensen patent. The validity of all the claims of the Jensen patent is admitted. The sole defense of the appellants is noninfringement.

The operation of the Jensen machine is best illustrated by the cuts which were admitted in evidence. In cut I, "Jensen's Can-Feeding Mechanism," the endless traveling belt is designated by the letter A. The filled cans are placed upon it in a vertical position. The belt passes around drums at each end, the drums being operated by appropriate mechanism. The device marked, j, j, described in the patent as arms, are used as spacing devices for the cans. They allow them to move forward so as to arrive at the feeder in proper time to be received by it and carried forward. The arms which are connected together by the chain, k, have an intermittent motion back and forth in the direction of the belt. The letter E designates the transverse stop, consisting of a stationary bar, which arrests the forward progress of the can. The next element is the feeding device, which receives the can where it is stopped in its forward movement, and transfers it from the belt to the capping mechanism, which is shown in the cut marked II, “Jensen's Feeder," where it is designated by the letter F. It consists of a transverse bar, with four arms at right angles thereto, the arms being marked by the letter H. The capping mechanism of the feeder consists of three cranks, lettered J, J, J, operated by a mechanism which imparts a circular, sweeping motion to the feeder. The can is first received between the first two arms of the feeder, and is swept off the belt by the circular, sweeping motion of the feeder, and is left on the table to be further moved by the second motion of the feeder, which grasps it between the second two arms, and places it on the lower plunger, beneath the capping mechanism. The cut III, "Jensen's Cap Feeding Mechanism," shows the apparatus for feeding the caps. Caps are placed on an angular chute, designated by the letter Q. At the bottom of the chute is a spring arm, P, which stops the caps and prevents their further movement down the chute until the proper time for releasing them. The letter N designates a trigger placed directly within the line of the travel of the moving cans, and attached to an arm, O, projecting upwardly so that, when the trigger is pressed by the can, the arm, O, pushes back the spring arm, P, and releases the cap which rests against it. By this mechanism each can body releases its own cap. The cap is then grasped by other mechanism and carried into the capping mechanism. The capping mechanism consists of a lower plunger, upon which the can is delivered from the feeder; above it, a conical guide, within which the upper end of the can is forced; two slides, adapted to move towards each other transversely, having their ends shaped in a semicircle, so that when they come together they form a complete circular space. An annular rim is cut in the face of these slides, in which the capping fits and rests. When the can is placed on the lower plunger, the plunger rises by appropriate mechanism,

pushes the upper end of the can through the conical guide which serves to size the upper end of the can in perfect alignment for the caps, and inserts the can in the cap. An upper plunger holds the cap in place, and, after the can is capped, descends on top of the can, holding it steady, while the semicircular slides recede and allow the capped can to pass through the conical guide and descend to the table where it is grasped between the last two arms of the feeder and carried to the crimping mechanism. In cut IV, "Jensen's Capping Mechanism," the lower plunger is marked S. Directly above it is the conical guide, marked T', T'. Immediately above the conical guide are the transversely moving slides, T, T. The upper plunger is marked U.

The appellants' machine is described as follows: Cut V, "Letson & Burpee Can-Feeding Mechanism," shows that combination of the machine which de livers the cans to the feeder. 59 is the endless traveling belt. B, B, are the cans resting thereon. The devices marked 79, 79, are the spacing devices separating the cans, and regulating their direction to the feeder. The device marked 36 is a recessed wheel on a spindle, and rotating across the surface of the belt. When the can reaches the wheel, it is caught in one of the recesses of the wheel as it rotates, and is thereby removed from the belt into a circular guideway, shown in the drawing, and is carried along the guideway to a disk which is the upper surface of the lower plunger. Cut VI shows the appellants' mechanism for delivering the caps. The caps are carried by an endless horizontal belt. Letter N represents the trigger in the path of the moving cans. The trigger is connected with a stop which restrains the caps on the carrying belt. When the can strikes the trigger the stop releases the cap, and the carrying belt carries the released cap to a device which places it on the capping mechanism. Cut VII shows the appellants' can-capping mechanism. The feeder, 36, is represented as having placed a can on the lower plunger. The plunger represented by the figure 19 consists of a disk on which the can rests, and a spindle passing loosely through a vertical hole in the rotating arm 14a. The bottom of the spindle moves on the stationary cam face, 46, which is an inclined plane. As the spindle moves on the cam, it is pushed upward through the conical guide, 21. Immediately above the conical guide are three transversely moving slides for holding caps. Above these slides is a second plunger, 26, called a "cap presser."

The claims of the appellee's patent which are alleged to be infringed are the following:

"(1) An endless traveling carrying-belt, a stop, E, extending across it to change the direction of the cans, and arms swinging over the belt, whereby the delivery of the cans from the belt to the feeder is rendered exact, substantially as herein described."

“(3) In combination with a transverse belt, the feeder having the projecting arms between which the cans are received from the belt and the actuating devices by which the motions of the feeder are produced, substantially as herein described."

"(5) The inclined chute into which the caps are placed, and a stop extending across said chute, so as to prevent the caps from moving downwards, in combination with a trigger extending across the path of the cans as they are moved toward the capping table, said trigger being connected with the stop, 30 that, as it is moved backward by the passage of the can, it withdraws the stop to allow a cap to move down the chute, substantially as herein described." "(9) The vertically moving plunger upon which the cans are delivered by the feeder, in combination with the conical guide situated above the cans, and the transversely moving slides upon which the caps are received and held, with a mechanism by which the slides are withdrawn as the can enters the cap, substantially as herein described.

"(10) The vertically moving plunger by which the can is raised to receive the cap, and the guide into which the upper end of the can enters the transversely moving cap-holding slides, in combination with the second plunger moving vertically above the cap, and following it down by gravitation or otherwise, so as to steady the can in its descent after the cap has been applied, substantially as herein described.

"(11) The vertically moving plunger upon which the can is received, a carrier for placing the can upon the plunger, and a mechanism by which this