phone to the various switch shanties, where the switch tenders, at phones therein, receive them, and execute them by transmitting them verbally or by signal to the engine or train crews, and by manipulating the switches, so that trains may take their proper tracks without coming in contact with each other or with the various switch engines and cars being switched and moved thereabout. Defendant had a rule requiring trains passing through the yard to reduce speed and proceed only after the way is seen or known to be clear. This use of the telephones by the switch tenders in connection with the movement of the trains was not occasional or exceptional, but was part of their general and usual duties; each train movement so communicated to the crews, or participated in by the switch tender, being preceded by his reception of a telephoned order directing it.

Our decision of August 6, 1915, in Chicago, Rock Island & Pacific Ry. Co. v. United States, reported in 226 Fed. 27, 141 C. C. A. 135, and followed by us in Chicago & Northwestern Ry. Co. v. United States, 226 Fed. 30, 141 C. C. A. 138, is against the proposition, advanced for plaintiff in error, that the 16-hour limit, and not the 9-hour limit, applies; and upon the authority of those cases the judgment of the District Court must be and is affirmed.

(244 Fed. 946)

FOSTER v. T. L. SMITH CO. et al.

(Circuit Court of Appeals, Seventh Circuit. February 1, 1917. Rehearing Denied July 26, 1917.)

No. 2360.

1. PATENTS 328-VALIDITY AND INFRINGEMENT-CONCRETE MIXER. The Smith patent, No. 803,721, for a concrete mixing machine, while for a combination of old elements, covers a new and useful combination, not anticipated, and discloses invention; also held infringed as to a number of claims, but claim 5 held invalid, as a duplication of another claim.

2. PATENTS

27(1)—INVENTION-ADAPTATION TO ANOTHER ART.

It is usually true that the observation and the imagination of the inventor are required to make adaptations from one art to another. 3. PATENTS 234-INFRINGEMENT FORMAL CHANGES.

Infringement is not avoided by changes in the mechanism of the patented device, so as not to literally conform to the language of the claims, if the defendant has appropriated the real substance of the invention.

Appeal from the District Court of the United States for the Eastern Division of the Northern District of Illinois.

Suit in equity by the T. L. Smith Company, the Jaeger Machine Company, and the Waterloo Cement Machinery Corporation against

For other cases see same topic & KEY-NUMBER in all Key-Numbered Digests & Indexes

Edward Foster. Decree for complainants, and defendant appeals. Affirmed in part.

By the decree of the District Court appellant is enjoined from continuing the infringement of claims 5, 16, 17, 18, 28, 30, 31, and 32 of patent No. 803,721, issued on November 7, 1905, to appellee the T. L. Smith Company, as assignee of the applicant, Thomas L. Smith, for a machine to mix concrete. The other appellees are joint, exclusive licensees of the Smith Company. Appellant is the owner and user of a single machine, which was manufactured and sold to him by the Cement Tile Machinery Corporation of Waterloo, Iowa, which is defending this suit.

Figures 1 and 3 of the drawings are as follows:

Smith's specific description of the form which is stated in the patent to be the preferred form discloses a polyhedric mixing receptacle and a tiltable supporting frame which is in a plane at right angles to the receptacle's axis of revolution. To the specific details of this preferred form many claims were addressed, of which claim 24 may be taken as illustrative:

"In a mixing machine, the combination of a polyhedric mixing receptacle, a tiltable frame supporting said receptacle, means for tilting said frame to any position in the entire circle of its revolution, a gear attached to the periphery of said receptacle, said gear having supporting surfaces and guiding surfaces whereby said receptacle is completely centered and guided, and means for applying the power to said gear in any position of said receptacle and tiltable frame."

But the specification pointed out that the form of the mixing receptacle was not of the essence of the general inventive concept, and stated that a receptacle of any desired shape might be employed. Likewise, with respect to the preferred form of frame which entirely surrounds the revolving receptacle and supports it by means of rolls 17 fitting into the U-shaped annulus 22, the specification stated that the invention in its general aspect might be enjoyed by the use of a tiltable frame of "any desired form adapted for supporting the mixing receptacle."

None of the claims counted on in this suit is limited to the specific form of receptacle or tiltable frame or of the annulus on the receptacle.

Claim 5: "In a mixing machine, the combination of a receptacle provided with means for charging and discharging the same, a ring or annulus around the receptacle and provided with teeth forming an annular rack, a tiltable frame in which the receptacle is revolubly supported, said frame provided with projecting trunnions mounted rotatably in suitable bearings, one of said trunnions being tubular, a shaft extending through the tubular trunnion and provided on its inner end with a gear-wheel engaging the annular rack bar of the ring or annulus, and means for rotating said shaft."

Claim 16: "In a mixing machine, the combination of a mixing receptacle having one clear and unobstructed opening for feed and discharge, concentric, or substantially so, with the axis of revolution, a tiltable frame in which the receptacle is revolubly supported, means for tilting the frame to any position in the entire circle of its revolution, whereby the receptacle may be filled from any point above it and discharged either from the right-hand side, or the left-hand side of the machine."

Claim 17: "In a mixing machine, the combination of a mixing receptacle, means for imparting to said receptacle a continuous rotation, a tiltable frame revolubly suporting such receptacle, means for tilting said frame to any position in the entire circle of its revolution, and means for holding said frame in any position."

Claim 18: "In a mixing machine, the combination of a mixing receptacle, a tiltable frame revolubly supporting said mixing receptacle, means for tilting said frame to any position in the entire circle of its revolution, and means for continually revolving said receptacle while in any tilted position, or while moving from one position to another."

Claim 28: "In a mixing machine, the combination of a mixing receptacle having one clear and unobstructed opening for feed and discharge, concentric or substantially so, with the axis of revolution, a tiltable frame supporting said receptacle, means for tilting said frame either to the right or to the left of the loading point, a gear on said mixing receptacle, and means for applying power to said gear in any position of said frame and receptacle." Claim 30: "In a mixing machine, the combination of a mixing receptacle having one clear and unobstructed opening for feed and discharge concentric or substantially so, with the axis of revolution, a tiltable frame supporting said receptacle, means for tilting said frame either to the right or to the left of the loading point, a gear disposed around the middle of said receptacle, and means for applying power to said gear in any position of said receptacle and tiltable frame."

Claim 31: "In a mixing machine, the combination of a mixing receptacle having one clear and unobstructed opening for feed and discharge concentric, or substantially so, with the axis of revolution, a tiltable frame supporting said receptacle, means for tilting said frame either to the right or to the left of the loading point, a gear on the largest diameter of said receptacle, and means for applying power to said gear in any position of said frame and receptacle."

Claim 32: "In a mixing machine, the combination of a mixing receptacle having one clear and unobstructed opening for feed and discharge concentric, or substantially so, with the axis of revolution, a tiltable frame supporting said receptacle, means for tilting said frame either to the right or to the left of the loading point, a circular toothed rack disposed around the middle of said receptacle, a bevel pinion engaging said toothed rack and journaled in

the tilting axis, and means for connecting said pinion with the source of power."

The commercial machines of the respective parties are substantially alike. We subjoin a cut of the Waterloo mixer:

George C. Kennedy, of Waterloo, Iowa, and John E. Stryker, of St. Paul, Minn., for appellant.

George L: Wilkinson, of Chicago, Ill., for appellees.

Before BAKER, MACK, and ALSCHULER, Circuit Judges.

BAKER, Circuit Judge (after stating the facts as above). [1] I Utility is presumed; but if we first apprehend the nature and advantages of the machine which Smith conceived, we shall be in a better position to understand and apply the prior art.

Smith's most general conception of his machine as an entirety is probably best stated in claim 32. There, the only limitations upon the form of the mixing receptacle are that it shall have but one opening, which must be clear and unobstructed and substantially concentric with the axis of revolution, and that it shall have a recognizable "middle." The advantages of the one clear and unobstructed opening are that it may be used both for feed and discharge; that the feed may be one side where the materials are gathered and the discharge on the other side where the mixed concrete is being used; and that thereby a form of receptacle is provided wherein more than 50 per cent. of the cubic capacity can be occupied by the ingredients that are being mixed, as against 10 or 15 per cent. in the cylindrical or horizontal drum machines which have openings at each end, one for feeding and the other for discharging. The saving of size and weight, in relation to the capacity of the machine, smaller cost of manufacture, lower selling price, decreased expense of operation, are of advantage both to the maker and the user. By having a "middle" part, as in a pot or jar, the tilting means and likewise the rotating means are applied