The suit is for infringement of United States letters patent No. 437,667, September 30, 1890, to Henry B. Cutter, as joint inventor with and assignee of Lucius T. Stanley, for “improvements in electrical switches.” The specification states that the “main purpose has been to produce a neat and ornamental switch mechanism, which may be applied and used in any‘house or room without disfigurement, and which at the same time shall be complete and effective as a devise for making and breaking a heavy current; and our further object has been to improve the construction and mechanical details of the switch mechanism itself.” It will not be necessary to quote from nor discuss such portions of the specification and drawings as describe the" alleged improvements in. the details of the switch mechanism and the particular arrangement of mechanical parts which makes the device effective when the current is heavy. Such portions of the patent might be quite material in connection with the prior history of the art, if the first three claims were under discussion. But at the very outset of the case, while taking its prima facie testimony, the complainant, by its counsel, expressly stated that “it relies on the fourth and fifth claims * * * as the claims infringed by the defendants,” and those two claims only have been relied upon in argument in this court. These claims are as follows:
“(4) In an electric switch, the combination with a rocking lever constituting a part of the operative parts of a switch mechanism, of a fáce-plate for enclosing said switch mechanism in a suitable receptacle, and push-buttons passing through said face-place, and connected • with opposite ends of said rocking lever, as set forth. (5) A spring-actuated electric switch, adapted to be inserted in a recess in a wall, and" a pivoted lever for operating the same, in combination with a face-plate for covering said recess and inclosing said switch, and push-buttons passing through said face-plate and connected with the lever of the switch mechanism, whereby the switch may be set, in action or operation to make or break circuit by pushing one or the other of said buttons.”
Electric switches spring-actuated and with rocking or pivoted levers had theretofore been inserted in suitable receptacles, such as