that it will not reach the switch-box until at least the forward wheels of the car have passed the junction of the main and branch tracks. Thus the switch-box will guide the wheel automatically upon that one of the trolley-wires which corresponds with the track upon which the car has been directed.

The patent contains thirty-five claims, all of which are said to be involved, except those relating to the fender for the trolley-wheel. These so-called "fender claims," numbered 18, 28, 29, and 30, were withdrawn at the argument. The other claims may be divided into groups, as follows:

Claims relating to the construction and attachment of the conductorswitch:

1. The combination, with crossing or branching overhead wires, of a plate along the top of which said wires pass, and deflecting-ribs at the lower side of said plate at its extremities.

2. The combination, with an overhead conductor arranged to receive a traveling underneath contact, of a switching device secured to and depending from the conductor.

3. The combination, with an overhead wire for receiving an underneath contact, of a switch-plate attached to the wire in about the same horizontal plane as the wire.

9. In an electric railway, a switching device for suspended conductors, comprising two or more branching compartments or ways corresponding to the direction of the track, and of the main and branch conductors, and secured to the said suspended conductors, substantially as described.

10. In an electric railway, a switching device for suspended conductors, consist ing of an open-bottom box formed with two or more branching compartments corresponding to the direction of the track and arranged to be secured to the conductor, substantially as described.

11. The combination, with an overhead line-wire, of a grooved contact device pressed against the wire and receiving the wire between the flanges of the groove, and a guiding switch-plate connected to the wire against which the said flanges bear in passing from one line to another.

12. In an electric railway having an electric conductor suspended above the track, a switching device supported by the conductor and formed with downwardly-open compartments or ways corresponding with the direction of the track, said ways being substantially flat at their upper sides to form paths for the flanges of the contact-trolleys, substantially as described.

13. In an electric railway, a switch for suspended conductors, consisting of a box formed with branching compartments corresponding with the branches of the conductor, and of the track-switches and secured to the said suspended conductors, substantially as described.

14. In an electric railway, a switch for suspended conductors, consisting of a box formed with branching compartments corresponding with the branches of the conductor, and of the track-switches, and secured to and depending from the said suspended conductor, substantially as described.

19. In an electric railway, the combination with branching overhead conductors, of an upwardly-pressed contact-arm carrying a grooved wheel embracing the conductor, and a switch-plate at the branching point adapted to receive the tips of the wheel flanges, and provided with depending ribs, between which the wheel is free to move laterally to engage with one of the branch conductors.

23. The combination, with branching overhead conductors, of a vehicle having a laterally-swinging contact-arm pressed upward to engage the conductors and a

switch-plate at the branching point having depending sides, but open at its extremities, the interior width of the plate between the sides being greater than the thickness of the contact-wheel, whereby the wheel is free to move laterally with relation to the main conductor and engage one of the branching conductors.

Claims relating to the centralizing-spring:

21. In an electric railway, the combination, with main and branch overhead conductors, of a vehicle, an intermediate contact-arm thereon movable laterally with respect thereto, a spring tending to return the arm to its normal central position, a guiding-switch at the branching point of the conductor, and a track-switch for the vehicle located so as to operate in advance of the conductor-switch, whereby the lateral tendency of the contact device at the branching point is imparted to it by the vehicle, while its outer extremity is flexibly guided by the overhead switch from main to branch conductor.

24. In an electric railway, the combination, with branching line-conductors, of a track-switch, a vehicle, an intermediate contact-arm swinging laterally with respect to the vehicle, but provided with a spring tending to restore it to its normal central position, and a lateral deflecting-switch at the branching point of the conductors, whereby the extremity of the contact-arm may be flexibly guided from main to branch conductor.

31. In an electric railway, the combination, with an overhead conductor and a vehicle, of an intermediate contact device consisting of a trailing arm having a grooved contact-wheel at its outer end and moving laterally relatively to the vehicle, · but provided with a spring tending to retain it in its normal central position.

32. In an electric railway, the combination, with an overhead conductor and a vehicle, of a trailing contact-arm guided at its outer end by the overhead conductor, and movable laterally relatively to the vehicle, but having a normal centralizing tendency by means of a spring or weight.

33. In an electric railway, the combination, with an overhead conductor and a vehicle, of an intermediate contact device consisting of an upwardly-pressed trailing arm having a grooved contact-wheel at its outer end by which it is guided by the conductor, the said arm being free to swing laterally relatively to the vehicle, but tending to remain in its normal central position by means of a spring or weight. 34. The combination, with a vehicle and an overhead conductor, of a trailing contact-arm guided normally by the conductor, but having a spring-connection with the vehicle tending constantly to maintain it in a definite position, while at the same time it is free to swing laterally with respect to the vehicle against the pressure of the said spring.

35. In an electric railway, the combination, with an overhead conductor and a vehicle, of an intermediate contact device consisting of a rearwardly-extending arm guided at its outer extremity by engagement with the conductor and movable laterally relatively to the vehicle, but having a spring or weight tending to restore it to its normal central position.

Claims relating to the weighted tension-spring:

15. In an electric railway, the combination of a car, a conductor suspended above the line of travel of the car, a contact-carrying arm pivotally supported on top of the car and provided at its outer end with a contact-roller engaging the under side of the suspended conductor, and a weighted spring at or near the inner end of the arm for maintaining said upward contact, substantially as described.

16. In an electric railway, the combination of a car provided with a pivoted arm, as F, having a contact at its outer extremity, a tension-spring, as G, attached at its inner extremity, and a vertically-moving weight connected to said spring for holding the same in operative relation to the arm throughout its entire range of movement, substantially as described.

17. In an electric railway, the combination of the car having suitably-pivoted arm F, carrying a contact-wheel at its outer extremity, a spring G, secured to its lower extremity, and a connection extending from said spring and provided with a weight at its lower end, substantially as described.

Claims relating to the directive action of the track-switch or the combination of the conductor-switch and trolley with the track switch:

4. The combination of a track having switches, an overhead conductor above the track and having switches, and a car on the track provided with a contact-carrying arm arranged to engage the conductor at a point in rear of the front wheels of the

car.

5. In an electric railway, the combination of a track having suitable switches, an electric conductor suspended above said track and having switches located above the track-switches, and a car on said track provided with an upwardly-extending arm carrying a contact-wheel arranged to engage the suspended conductor at a point in rear of the front wheels of the car, substantially as described.

6. In an electric railway, the combination of an electrically-propelled car, a supplyconductor suspended over the line of travel of the car, a swinging arm mounted upon the car and carrying a contact device at its free end, said contact arranged to bear against said conductor, suitable switching devices upon the track traversed by the wheels of the car, and corresponding switches on the suspended conductor located above those on the track and arranged to engage the contact devices, substantially ⚫ as described.

7. In an electric railway, the combination of a track having suitable switches, an electric conductor suspended above said track and having switches located above the track-switches, a car on said track provided with a swinging arm carrying a contact-wheel arranged to engage the suspended conductor, and switches at a point in rear of the front wheels of the car, whereby the contact-wheel is directed through the proper part of the suspended switch, substantially as described.

8. In an electric railway, the combination of a switch or turn-out on the track and a corresponding one on the overhead line, the same being so arranged relatively that the car will reach the switch or turn-out before the trolley does, substantially as described.

20. In an electric railway, the combination, with an overhead switch-plate having depending ribs, but open at its extremities, of main and branch conductors extending from its two extremities, respectively, a vehicle, an upwardly-pressed contactarm attached to the vehicle and tending to move laterally therewith, and a trackswitch for the vehicle located so as to operate in advance of the conductor-switch. 22. In an electric railway, the combination, with main and branch conductors, of a vehicle, a contact-arm thereon having vertical and lateral spring-pressure, a switchplate for the conductors, and a track-switch for the vehicle located so as to operate in advance of the conductor-switch, whereby the lateral tendency of the contact device at the branching point is imparted to it by the vehicle, while its outer extremity is flexibly guided by the overhead switch from main to branch conductor. 25. In a branching electric railway, the combination of a track-switch, an overhead conductor-switch, and a vehicle having a rearwardly-extending contact-arm, whereby the track-switch will operate in advance of the conductor-switch.

26. In a branching electric railway, the combination, with a vehicle, of a trackswitch, an overhead conductor-switch, and a contact-arm extending upward from the vehicle to the conductor, and so located relatively to the length of the vehicle and the two switches that the lateral movement of the vehicle will give a corresponding movement of the contact device on the conductor-switch.

27. In a branching electric railway, the combination, with a vehicle, of a trackswitch, a contact device consisting of a trailing spring-pressed arm having a grooved contact-piece embracing the conductor and guided thereby, the said arm being

jointed to the car and tending to move laterally therewith, and an overhead conductor-switch adapted to engage the contact-piece and whereby the extremity of the arm is flexibly guided from main to branch conductor.

The parties do not agree as to the grouping of some of these claims; but it is thought that the above arrangement is as convenient as any. The defenses are anticipation, lack of patentability, non-infringe ment, and, as to a part of the defendant's cars, estoppel because of an alleged license.

COXE, J.:

The patent in controversy deals with a comparatively new art. Electricity has so completely supplanted horse-power as a means for propelling street-cars that it is difficult to realize that only about ten years have passed since the first successful electric railroad was installed. At the present time there are more than five hundred roads in operation, employing an immense army of workmen and a vast amount of capital. That this wonderful result was accomplished only after innumerable difficulties and obstacles had been encountered and overcome is manifest. The potentialities of the art attracted a large number of brilliant and ingenious men, who for more than a decade have been laboring to make electric railroading successful. Even after the necessities of the situation had evolved the fundamental principle of taking the electricity from an overhead conductor the difficulties in finding suitable contact and switching devices for a long time prevented commercial success, and the solution of the problem taxed the ingenuity of a large number of inventors. Although the electric road of to-day is a composite organism to which many ingenious and able men have contributed, yet it cannot be denied that to. Van Depoele, more than to any other man, belongs the credit of having made it a practical working success. His contributions to the art rapidly supplanted the crude and tentative prior structures and have continued in use until the present time. No one can read this record without being impressed with the truth of this proposition, and, this being so, the court naturally approaches this controversy in liberal spirit and with an inclination to give the inventor the full fruits of his invention. If there be any deviation from this determination, it is due to the fact that he has obscured his real invention in a multitude of fuliginous and attenuated claims, many of which can only be distinguished when their language is subjected to the most searching analysis. He has particularly pointed out his invention in the description; but, because of this seemingly needless verbosity, he has claimed it indistinctly, to the annoyance of the public, and especially that part of the public which is called upon to construe the patent. A fair amount of tautology and reiteration is prudent and permissible in the claims of a patent; but it is hardly conceivable that it requires thirty five claims to secure a comparatively simple mechanical invention. Where the patentee has taken

pains to cover every shadow of a shade in his claims, the range of construction is limited and he must be held strictly to language which he has adopted with such painstaking deliberation and exactness.

Generally speaking, the patent covers devices and combinations by which electric cars are run automatically upon branches and turn outs, the motor being supplied from an overhead system of wires. This is done by a trailing underrunning trolley mounted on a long pivoted arm supported on the top of the car and pressed up against the wire by a spring or equivalent device. This arm has sufficient horizontal and perpendicular movement to adjust itself automatically to the wire, although the wire may not at all times be directly above the center of the rails or suspended at the same distance above the car. The conductor without leaving the platform of the car has full control of the trolley. The other important device used by the inventor is an overhead switch so mounted on the wire that when the forward wheels of the car take the track-switch a trend or direction is given to the trolley so that when it reaches the overhead switch it is guided to the proper branch automatically without in any manner disturbing the electric current or the running of the car. In this way a system is produced which is well-nigh perfect in its essential details. That it was necessary in order to attain this result to surmount many difficulties and solve many problems might almost be assumed by the court; but it is abundantly proved by the record.

It is argued by the defendant that the patent is void because all of the inventions claimed therein, except claims 15, 16, and 17, which are not infringed, are covered by earlier patents to Van Depoele. There is no dispute as to the law. It is fundamental that two patents cannot be granted for the same invention. Where two patents for the same invention issue to the same person, the second patent is void. The Supreme Court in Miller v. Manufacturing Co. (C. D., 1894, 147; 66 O. G., 845; 151 U. S. 186; 14 Sup. Ct., 310,) lays down no new rule of law. It simply adheres to the old rule, which is well stated in the syllabus, as follows:

No patent can issue for an invention actually covered by a former patent, especially to the same patentee, although the terms of the claims may differ.

The second patent, in such case, although containing a claim broader and more generical in its character than the specific claims contained in the prior patent, is also void.

But where the second patent covers matters described in the prior patent, essentially distinct and separable, and distinct from the invention covered thereby, and claims made thereunder, its validity may be sustained.

The question here is, are the inventions of the patent in suit all covered by prior patents to Van Depoele? The patent chiefly relied upon by the defendant is No. 397,451, dated February 5, 1889, for improvements in "overhead contacts and switches." The application was filed November 12, 1888, while the application for the patent in suit was H. Doc. 354-9