This is a suit for infringement of letters patent No. 1,-233,107, for a road-building -machine, dated July 10, 1917, issued to Rolla M. Myers, and assigned to appellee; - of patent No. 1,401,-149, for combined spreader and roller, dated December 27, 1921, issued to appellee, as assignee of Harry C. Poster; and of patent No. 1,470,157, for a stone spreader, dated October 9,1923, issued to appellee as assignee -of Joseph L. Pike.

It is alleged in the complaint that the inventions, covered by said letters patent,' are capable of joint use, and are intended to be jointly used in road machines, manufactured and sold by appellee, and in similar machines, manufactured and sold by appellants, and that the appellee is now the sole owner of said letters patent, and all the rights thereunder, including the right to recover for past infringement; that the appellants jointly and severally infringed said letters patent and each of them by making, selling, and using, or causing to be made, sold, and used, machines, containing the inventions of said letters patent and the claims thereof. The bill of complaint contains the usual allegations of irreparable damage and injury to the appellee by reason of said infringement, as well as the usual prayer for injunctive relief and damages. ’

The- appellants have denied the material allegations of the bill of complaint, and have pleaded certain separate #nd alternative defenses, among others that said letters patent, and each of same, are void for aggregation, the subjects of none of same and the claims of none of saíne reflecting or amounting to invention; that such machines or devices, or instrumentalities, as appellants have made and sold, embody and contain and reflect invention and acts of invention totally distinct and different from the inventions of said letters patent, being in part the inventions of the appellant Butler, for which inventions application 'for letters patent of the United States have heretofore been filed by him, and which inventions are to be distinguished patentably from said alleged inventions of said letters patent mentioned in the bill of complaint; and that appellee’s patents were anticipated in and by numerous pribr letters patent of the United States and in foreign countries.

The lower court entered an interlocutory decree in favor of the appellee, plaintiff below, and this ease comes here on appeal from that order.

Appellee began the manufacture of the stone spreader and distributer in the year 1917. The value in money of the machines so manufactured amounts to approximately $320,000. The total number of machines so manufactured, up to the time of the commencement of this suit, is slightly in excess of 1,000 machines.

The evidence shows that, prior to the time appellee’s machine came into general use throughout the United States, the prevailing method of distributing road material on the roadway was to dump it out of the truck or wagon and distribute it over the surface of the road by hand. This method was inefficient, expensive, and unsatisfactory, it being almost impossible to distribute evenly the different grades of material over the road, or to • distribute same to a given thickness; whereas, by the use of appellee’s spreader, which regulated the amount of material to be placed bn the road, the proper amount of such material could be distributed evenly and without any guesswork, and this regardless of the condition of the subgrade. Under proper conditions, 2 men on the spreader did the same work that 14 men did by hand..

Appellee insists that the patents in suit are in themselves prima facie evidence of validity, and of the truth of the facts therein stated. On the other hand, the appellants contend that the issuance of the patents to Butler creates a prima facie presumption of the patentable difference from that of the appellee’s patents. We think it unnecessary to review the many authorities cited in support of these propositions. It will suffice to quote from the opinion of the Supreme Court in the case of Coming et al. v. Burden, 15 How. (56 U. S.) 252, 270 ( 14 L. Ed. 683 ):

The Myers Patent, No. 1,233,107.

The invention as described in this patent is set forth in the second paragraph of the specification:

*18 The patent discloses a structure comprising what is described in the specification as a hopper-shaped casing, consisting of front and rear walls 2 and 3, and end walls 4; the top of the easing, as shown in the drawings, is open so as to permit the flow into it of the material from the dumping truck. Approximately one-half of the rear wall of the casing is omitted, namely, the lower portion of the said wall, and the opening so formed, together with the open bottom, forms the outlet through which the stone passes onto the roadway. This opening is narrower than the opening at the top, due to the fact that the rear wall is practically vertical, while the front wall inclines upward at an angle.

Shoes 7 and 8 and wheels 14 act as support for the structure and prevent it’ from sinking into the soft ground. The structure is attached to the truck by chains 11, fastened to said shoes. These chains have hooks 12 at their forward ends, and the hooks are adapted to engage eyes 13 on the rear axle of the truck 1. The operation of the device is described as follows:

Patentee claims:

The structure is shown in the drawings:

The Foster Patent, No. 1,401,149.

As stated in the specification:

This patent discloses a hopper-like structure similar to that of the Myers patent. “The present invention, however, embodies improved means for regulating the shape and extent of the deposited mass of material and the use of a pressure roller for preparing the surface to receive such deposits.”

“Pivotally mounted in the skids 4 and extending transversely across the apparatus, and immediately in front of the divergent front wall 2, is a pressure roller 5. As shown in Mg. 2 this pressure roller 5 extends somewhat below the lower edge of the skid. Inasmuch as the roller 5 is located beneath the inclined forward side 2, it approaches quite closely to the vertical plane of the center of gravity of the hopper when loaded. The construction is such that the hopper 1 rides primarily upon the roller 5 with the rear ends of the skids trailing upon the ground. The skids not only limit the tilting movement of the hopper, and prevent it being upturned, but also facilitate the movement of' the device over depressions or ridges and uneven surfaces. The construction is such that the roadbed or receiving surface is compressed by the roller action, as the drag is moved forward. The surfacing action is effected immediately in advance of the deposit of material from the hopper.”

The claims involved herein and the drawings are as follows:

*21 The Fike Patent, Fa 1,470,157.

The specification sets forth:

Neither the Myers nor the Foster patent has any provision for the overhang over a previously distributed course, nor for the lateral discharge opening at the end of the easing.

The claims of this patent involved herein and the drawings are as follows:

*23 The Butler Patent, No. 1,581,784.

As stated in the specifications :

The claims and drawings are set forth in full in the margin. 1

The Butler Patent, No. 1,605,094.

The specification states:

The claims and drawings of the patent are also set forth in the margin. 2

*24 Appellants insist that the three patents in suit are invalid, in view of the prior art. The Circuit Court of Appeal for the Second Circuit has said that the principal question in cases of this character is:

As to the Prior Art.

The British patent to Stone, No. 1,115, is for “an improved system of easting or moulding applicable to ceilings, internal and external-walls, roads, navigable vessels, and *25 other large surface structures.” It was issued in 1872, and describes a traveling hopper, mounted on wheels and operated on rails, and which contains material to be deposited upon the roadway. The specification contains the following statement:

There seems to he a vast difference in this patent and the patents in suit. It does not seem to contemplate the nse of a spreader in connection with a vehicle or truck containing the material to ho used on the roadway, as described in the said throe patente, or either thereof, nor is it capable of such use.

The Sehellenger patent, No. 1,029,894, is for a distributer for dumping wagons and ears, issued June 18, 1912. In this patent provision is, made for the delivery of the road material in advance of the rear wheels of a horse-drawn vehicle, and not from a machine used in combination with a motor truck, which truck delivers the material at the rear.

In the first place, the Sehellenger machine is so constructed that it cannot lay the material in width as great as the width between the wheels of the wagon. Figure 2 of the drawing illustrates this. In the second place, it is not clear how the space or channel between the strips of roadbed is to be filled. The specification provides: “These intervals between the first-named strips of roadbed may be afterward filled to a uniform depth by driving the wagon upon the parallel strips of road-making material first distributed, and by turning up the side boards 38, as previously described. Fig. 2 shows a cross-section of a roadbed with two parallel strips of road-making material, so placed as to leave an interval between the strips, which interval may he afterward filled as above described.”

Such a device could not compare favorably with or anticipate the patents in suit, or provide for a uniform distribution of the road material along the roadway. In the machine of the Myers patent in suit the adjoining layers of material are close together, thus avoiding the necessity of hand laboj-, or of driving the wagon over parallel strips of road-making material as above provided in the Sehellenger patent.

The evidence in the ease, as well as the specifications and drawings of the Myers and t Sehellenger patents, show a decided structural difference. We therefore conclude that the Sehellenger patent is not pertinent to the Myers disclosure and does not anticipate the same; furthermore, that the teaching of the patents in suit is not carried out in either of these two patents, or in any of the other patents cited as constituting or shown in the prior art.

One of tlie witnesses in the ease has correctly stated: “There is nothing in the prior art which anticipates the fundamental idea of the Myers patent, of a combination of a dumping truck, with a distributing machine located at the rear of the truck, so that the material falling from the truck will fall into it, and in contact with the ground, and as a leveling device or gauge which determines the thickness of the material spread upon the ground.”

This patent does not disclose “the fundamental idea of the Myers patent, of the combination of dump vehicle — whether horse or motor drawn is immaterial — ¡-that discharges at the end of the vehicle, and an intermediary *26 device which is drawn on the ground in the rear of the vehicle, as a discharge gate or end gate, which controls the discharge, and that fixes the level of the layer discharged from the material.”

The supports of the hopper-shaped device of the Schellenger patent are materially different from those of the Myers patent; there is no roller in the Schellenger patent corresponding to the roller of -the Foster patent; neither is there any stepping arrangement corresponding to that of the Fike patent, nor gates at the end of the hopperlike easing that controls or regulates the lateral discharge of material at the ends of the easing.

It is true that Schellenger in his specification states: While I have illustrated my distributer as used with a wagon having a discharge opening disposed about midway of the wagon body, it will be obvious that the distributer might be used with a wagon discharging, in any other manner, as, for instance, from the rear; it only being necessary that the distributer shall be disposed immediately beneath the discharge opening of the wagon, so that the load as it is discharged from the wagon body will pass into the discharging hopper and by said hopper be distributed properly and to an even depth along the roadbed. * * * Neither do I wish to limit myself to any particular form of dumping wagon and gate therefor, as it is obvious that other forms of dumping vehicle than that shown, provided with other forms of discharge gate, might be used without departing from the spirit of the invention.”

It is, however, significant that he fails to amplify his statement by indicating what he had in mind, or to indicate in his drawings definitely the character of the machine or combination he had in mind, for distributing the road material upon the roadway, or its workings. Manifestly such 'a statement is entirely too general and indefinite.

These suggestions of what might be done do not carry conviction. “The claims of his patent limit his exclusive privileges, and his specifications may be referred to, to explain and to restrict, but never to expand, them.” Stirrat v. Excelsior Manuf’g Co. (C. C. A.) 61 F. 980, 984 . We do not think his claims warrant a construction broad enough to cover or anticipate the three patents in suit.

We have given due and careful consideration to the other patents cited as showing prior publication and anticipation, and arrived at the conclusion that the appellee’s structure was not anticipated by the prior art, that the combination involved invention, and that it was a step.forward in the art. The evidence shows that prior to the year 1917 there was nothing known to the art which would perform the functions of the Bui’eh spreader. Even if all the elements of the combination had been used before, and the functions of each were well known to the art, we think they have never been combined for effectuating the purpose accomplished by appellee.

We quote and adopt the testimony of one of the witnesses who testified in the ease as correctly stating the points of similarity between the machine of the three patents in suit and the machine manufactured by the defendants :

The patents in suit, in our opinion, do not describe a structure or machine operating in the same way as those described in the prior art, nor do they accomplish the same purpose by substantially the same means.

We think the inventions of these patents are incorporated in the appellant’s and appellee’s machines, as they are now constructed. While in the Butler machine the appellants do not use precisely all of the parts of the Burch machine, they do use mechanical equivalents for the absent parts, and the result is substantially the same.

Unquestionably there is some difference in the structure of the machines, but we think there is no difference in principle. We look more to the substance of things than their forms.

“Where a combination patent marks a distinct advance in the art to which it relates, as does the appellant’s invention here, the term ‘mechanical equivalent’ should have a reasonably broad and generous interpretation, and protection against the use of mechanical equivalents in a combination patent is governed by the same rules as patents for other inventions. Imhaeuser v. Buerk, 101 U. S. 647 , 25 L. Ed. 945 . The fact, if it be a fact, that the infringing machine is superior, more useful, and more acceptable to the public than that of -the appellant, does, not avoid infringement, so long as the essential features of the appellant’s patented machine are used, unless its superiority is due to a difference in function or mode of operation or some essential change in character. Morley Machine Co. v. Lancaster, 129 U. S. 263 , 9 S. Ct. 299 , 32 L. Ed. 715 ; Hoyt v. Horne, 145 U. S. 302 , 12 S. Ct. 922 , 36 L. Ed. 713 ; Lourie Implement Co. v. Lenhart, 130 F. 122 , 64 C. C. A. 456 ; Diamond Match Co. v. Ruby Match Co. (C. C.) 127 F. 341 ; Whitely v. Fadner (C. C.) 73 F. 486 .” Smith Cannery Machines Co. v. Seattle-Astoria I. W. (C. C. A.) 261 F. 85, 88 .

“Defendants therefore cannot escape infringement by adding to or taking from the patented device by changing its form, or even by making it somewhat more or less efficient, while they retain its principle and mode of operation and attain its results by the use of the same or equivalent mechanical means. Lourie v. Lenhart, 130 F. 122 , 64 C. C. A. 456 ; [Leston] Letson v. Alaska Packers’ Association, 130 F. 129 , 64 C. C. A. 463 ; Eck v. Kutz (C. C.) 132 F. 758 . By varying the encircling means, but producing the same results in substantially the same manner, there is infringement. Both physical and mechanical encircling, with centering, are found in defendants’ machine. Union Paper Bag Machine Co. v. Murphy, 97 U. S. 120 , 24 L. Ed. 935 ; Kinloch Telephone Co. v. Western Electric Co., 113 F. 659 , 51 C. C. A. [369] 362; Auto Pneumatic Action Co. v. Kindler & Collins [ (C. C. A.) 247 F. 323 ], supra; Pangbom Corporation v. Sly Mfg. Co. (C. *28 C. A.) 284 F. 217.” Angelus Sanitary Can Mach. Co. v. Wilson (C. C. A.) 7 F.(2d) 314, 318 .

Wé think the construction and mode of operation of the two machines are so similar that the Butler machine cannot be regarded as an independent invention.

Appellee’s title to the three patents in suit, and its right to the exclusive use of the invention, is clear, and there is no room for reasonable doubt as' to the infringement.

All of the assignments of error not herein referred to have been carefully considered. We find no error in the record, and the decree of the lower court is affirmed, with costs.

APPENDIX 1.

Butler Patent, No. 1,581,784.

“1. An apparatus for spreading hot materials, comprising a- receiver for the materials, having a rearwardly inclining bottom and a rear wall at an angle to the vertical, the bottom of said rear wall spaced from the bottom of said receiver to provide a discharge throat, means movable on said rear wall to control the transverse area of said throat, and rollers arranged in pairs supporting said receiver above the surface operated over.

“2. An apparatus for spreading hot materials, comprising a receiver for the materials, having a rearwardly inclining bottom and a rear wall spaced from said bottom, and providing a throat for the discharge of the material, means on and movable relative to said rear wall to control the transverse area of said throat, means on and movable relative to the side walls and said throat to control the width of said throat, strike-off means for the material, said means laterally movable relative to said first named means, and roll- ' ing means supporting said receiver above and free of the ground.

“3. An apparatus for spreading hot materials, comprising a receiver having a rearwardly inclining bottom, and a rear wall spaced from said bottom to provide a throat, means movable on said rear wall to control the transverse area of said throat, roller means supporting said receiver above the ground and disposed free of the throat in said receiver, strike-off means on and movable with and laterally to said control means, and means to control the movement of said strike-off means.

“4. An apparatus for spreading hot ma: terials, comprising a receiver, having an inclined bottom and an inclined rear wall spaced from said bottom to provide a throat for the material, roller means supporting said easing entirely above and free of the ground and disposed forward of the throat in said receiver, a blade on said rear wall, movable relative thereto and to the throat, to control the transverse area of said throat, means to operate said blade, partitions connected with said receiver and movable relative thereto and to said throat, to control the width of the throat, a strike-off plate on and movable with and relative to said blade, and means to operate said strike-off plate.

“5. An apparatus for spreading road materials, comprising a receiver for tbe material having a discharge throat in the rear thereof, a means to regulate the transverse area of said throat, to control the depth of material laid, adjustable means within said receiver to regulate the width of the throat, to control the width of the material laid, and means to lock said adjustable means in position of adjustment.

“6. An apparatus for spreading road materials, comprising a receiver for the materials having a discharge throat in the rear thereof, a blade movable on said receiver to control the transverse area of said throat, means to operate said blade, and means on said blade, forming extensions of same, to control the deposit of the material beyond the normal limits of the apparatus, and comprising plates having wings forming end walls for the throat, and means to operate said plates relative to said blade.

“7. An apparatus for spreading hot road materials, comprising a receiver having a rear discharge throat, roller means supporting said receiver entirely above the ground, a blade to control the transverse area of the throat, to regulate the depth of the material laid, plates on said blade, forming extensions thereof, to control the deposit of the material beyond the normal limits of the apparatus, means to agitate said material, and means to heat said agitating means.

“8. An apparatus for spreading hot road materials, comprising a receiver having a rear discharge throat, roller means supporting said receiver entirely above the ground, a blade to control the transverse area of the throat, to regulate the depth of the material laid, means to operate said blade, plates on said blade forming extensions thereof, to control the deposit of material beyond the normal limits of the apparatus, means to operate said plates relative to said blade, and a platform on said apparatus and extending longitudinally of the same and above the surface of the material laid.

“9. An apparatus for spreading hot materials, comprising a receiver for the materi *29 als, having a roarwardly inclining bottom and a rear wall at an angle to the vertical, the bottom of said rear wall spaced from the bottom of said receiver to provide a discharge throat, means on and movable relative to said rear wall, to control the transverse area of said throat, and selective means to control the deposit of material through said throat beyond the sides of the apparatus.

“10. An apparatus for spreading hot materials, comprising a receiver for the materials having a roarwardly inclining bottom and a rear wall spaced from the bottom of said receiver to provide a discharge throat, and means to heat the material in said receiver.

DEA WINGS.

“11. An apparatus for spreading hot materials, comprising a receiver for the materials, having a rearwardly inclining bottom and, a rear wall spaced from said bottom and providing a throat for the discharge of the material, means on and movable relative to said rear wall to control the transverse area of said throat, and means movable relative to-the side walls and said throat to control the width of said throat.

“12. An apparatus for spreading hot ma *30 terials, comprising a receiver having a rearwardly inclining bottom, and a rear wall spaced from said bottom to provide a throat, means movable on said rear wall to control the transverse area of said throat, means movable relative to the side walls to control the width of the throat, roller means supporting said receiver above the ground and disposed free of the throat in said receiver, and strike-off means on and movable with and laterally to said control means.

“13. An apparatus for spreading hot materials, comprising a receiver having a rearwardly inclining bottom, and a rear wall spaced from said bottom to provide a throat, means movable on said rear wall to control the transverse area of said throat, means movable relative to the side walls to control the width of the throat, roller means supporting said receiver above the ground and disposed free of the throat in said receiver, and strike-off means on said control means.

“14. An apparatus for spreading road materials, comprising a receiver for the material having a discharge throat in the rear thereof, a means to regulate the transverse area of said throat to control the depth of material laid, and means within said receiver to regulate the width of the throat to control the width of the material laid, and means to control the deposit of material through said throat beyond the sides of the apparatus.

“15. An apparatus for spreading road materials, comprising a receiver for the material having a discharge throat in the rear thereof, means to regulate the transverse area of the throat to control the depth of material laid, means to regulate the longitudinal area of the throat to control the width of the material laid, roller means supporting the receiver above the ground, and means laterally movable relative to the receiver to strike off deposited material.

“16. An apparatus for spreading hot materials, comprising a receiver having a discharge throat in the rear thereof, a blade to regulate the transverse area of said throat to control the depth of material laid, roller means supporting said receiver above the ground and free of the throat therein, and means on and laterally movable relatively to said blades to strike off deposited material.

“17. An apparatus for spreading hot materials, comprising a receiver having a discharge throat in the rear thereof, a means to regulate the transverse area of said throat to control the depth of material laid, roller means supporting said» receiver entirely above the surface operated over, means to heat the material, and a platform longitudinally of said receiver and above the surface of the material laid.

“18. An apparatus for spreading hot materials, comprising a receiver having a discharge opening therein, a means to regulate the transverse area of said opening to control the depth of material laid, and means on said receiver to strike off deposited material.

“19. An apparatus for spreading road materials, comprising a receiver having a discharge opening therein, a means to regulate the transverse area of said opening to control the depth of material laid, and a platform longitudinally of the receiver and above the surface of the material laid.

“20. An apparatus for spreading hot materials, comprising a receiver having a discharge opening therein, a means to regulate the transverse area of said opening to control the depth of material laid, roller means supporting said receiver above the ground and free of the opening therein, and a platform longitudinally of the receiver and above the surface of the material laid.”

APPENDIX 2.

Butler Patent, No. 1,605,094.

“1. In an apparatus for laying material, a casing having a rearwardly inclining bottom terminating in a downwardly extending apron, and a rear wall, a blade on said rear wall co-operating with said apron to form a chute having open sides, means to move said blade relative to said apron to control the transverse area of said chute, and roller means arranged in pairs and disposed in advance of the chute for supporting said casing entirely above the surface of the ground.

“2. In an apparatus for laying material, a easing having a rearwardly inclining bottom formed with an apron extending below said bottom, and a rear wall, a blade on said rear wall co-operating with said apron to form an open-sided chute below said bottom means to move said blade relative to said apron to control the transverse area of said chute, and means selectively operable to control the discharge of material through the sides of said chute.

“3. In an apparatus for laying material, a casing having a rearwardly inclining bottom formed with a downwardly extending’ apron, and a rear wall, a blade on said rear wall forming with said apron an open-sided chute below said easing, means to move said blade relative to said apron to control the transverse area of said chute, and means to control the passage of material through the *31 sides of said chute, said means movable with and independently of said blade.

DRAWINGS.

“4. In an apparatus for laying material, easing rollers arranged in pairs to support the easing entirely above the surface operated over, said casing having an inclined bottom terminating below said' casing, and a rear wall spaced from said bottom, a blade on said rear wail co-operating with the portion of the bottom terminating below the casing to form an open-sided chute, means to operate said blade on said rear wall to control the transverse area of said chute and means operable relative to the open sides of the chute to control the passage of material there-through.

“5. In an apparatus for laying material, a casing having a rearwardly inclining bottom formed with an apron extending below said casing, and a rear wall spaced from said bottom, a blade on said rear wall co-operating with said apron to form an open-sided chute below said casing, means for selectively moving said blade to control the quantity of material passing through said chute, and means for selectively controlling the quantity of material passing through the sides of said chute.”

.See Appendix 1 at end of case.

See Appendix 2 at end of case.