Reporter's Statement of the Case member pivoted on the trigger and projecting through a slot cut in the side of the receiver. A transverse slide member was incorporated into the breechbolt structure in such manner that when the breechbolt was closed and in firing position, one end of the slide was in operative relationship to the trigger element which projected through the slot in the receiver in such manner that when the trigger-motor plunger engaged the triangular trigger member the slide was moved across the face of the bolt provided the breechbolt was in a locked position. The movement of the slide was at right angle to the sear, which it engaged by means of coacting 45-degree cam surfaces. With each impulse transmitted through the oil line of the synchronizing gear the trigger motor actuated the triangular trigger and caused the transverse slide on the breech bolt to coact through the 45-degree cam surfaces with the vertical sliding sear so as to release the firing pin, provided the breechbolt was in locked position. If the impulse was delivered at any other time than when the breechbolt was not in a forward or firing position, the trigger member which projected through the slot in the receiver would not engage the transverse slide member and the movement of the trigger element was, therefore, simply an idling move ment. 15. Subsequently to March 1918 a series of contracts were given by the War Department to the Marlin Rockwell Corporation for the manufacture of 30,000 Browning aircraft machine guns adapted for use with the Constantinesco synchronizing gears. 16. Pursuant to a supplementary contract dated April 23, 1918, the Government advanced to the Marlin Rockwell Corporation the sum of $1,160,000 as a payment on account of the cost of the Marlin aircraft machine guns which the company had contracted to manufacture for the United States. On May 24, 1918, the Government entered into a contract with the Marlin Rockwell Corporation by which the Government agreed to purchase from the Marlin Rockwell Corporation, and thereafter did purchase from it, for the sum of $1,000,000, certain machines, tools, jigs, and Reporter's Statement of the Case dies which the Marlin Rockwell Corporation had been using in the manufacture of the Browning aircraft machine guns and many of which could be used for no other purpose than the manufacture of Browning aircraft machine guns, with or without the invention covered by the patent in suit. After the termination of the contracts for the manufacture of Browning guns, the aforesaid machines, tools, jigs, and dies were delivered by the Marlin Rockwell Corporation to the Government and placed in the Springfield Armory at Springfield, Massachusetts. 17. An application for a patent, serial number 516901, was filed in the United States Patent Office on June 11, 1918, in behalf of Carl G. Swebilius, the same being assigned to the Marlin Rockwell Corporation. The description and the drawings disclosed the breech bolt of an aircraft machine. gun and the trigger motor of the Constantinesco synchronizing gear, the impulses of the trigger motor being transmitted to the sear by means of a transverse slide inserted through a slot in the breech bolt. The application contained sixteen claims. The aforesaid slide was included as an element in all of the claims except claims 9, 12, 13, 14, and 15 which related to the structure of the trigger motor proper and means of attaching it to the gun. The Patent Office required a division and thereupon the applicant canceled claims 12 and 13 and added certain new claims. All of the new claims also included the slide as an element of the combination, except claims 18, 19, 22, and 25 which referred to the structure of the trigger mechanism proper. The examiner then rejected certain claims on prior art. Thereupon the applicant canceled claims 1, 2, and 3 and substituted three other claims in their stead, all of which included as elements a sear slidably mounted on the breechblock, and a slide mounted on the breechblock for reciprocation relative to said sear. The applicant argued that his claims were allowable over the references of record, since the claims recited the fact that the sear and sear slide were both mounted on the breechbolt, whereas in the references the sear alone was slidably mounted on the breechbolt, while the means intermediate the trigger and the sear Reporter's Statement of the Case were carried by the framework of the gun. On August 18, 1920, the application was allowed by the Patent Office. The applicant failed to pay the final fee within the time prescribed by law and the application lapsed. 18. The plaintiff, the Marlin Firearms Corporation, was incorporated under the laws of the State of Delaware in 1921. The Swebilius application was assigned by the Marlin Rockwell Corporation to the Marlin Firearms Corporation on or about August 24, 1921. On or about July 13, 1923, Louis H. Strouse and Eugene S. Bibb were appointed as receivers of the business, property, and assets of the Marlin Firearms Corporation. 19. November 23, 1921, the Marlin Firearms Corporation filed a petition showing that it was the assignee of the applicant's rights and renewing the Swebilius application. Thereafter the Marlin Firearms Corporation filed an amendment adding several new claims which read broadly on a combination, in an automatic gun, of a receiver, a breech bolt reciprocatively mounted therein, a movable sear carried thereby, a housing mounted on a wall of said receiver and means in said housing operatively connected with said sear for moving it in one direction, the slide not being expressly included as an element of the claim. A number of the claims were then rejected on prior art, among the references being the British patent to Maxim, #14047 of 1885. The examiner pointed out that some of the rejected claims recited a sliding sear, while Maxim showed a pivoted sear. The examiner added: "It is held, however, that no invention would be involved in substituting a sliding sear in Maxim, especially so, in view of the known use of sliding sears on breech blocks." The applicant again added new claims, all of which included the slide as an element, and requested a reconsideration of the rejection of the other claims, asserting that "to introduce a sliding sear into Maxim in place of the pivoted sear certainly involves the exercise of the invention faculty even in view of the sliding sears in the other patents." On reconsideration the examiner again repeated his rejection of certain claims and allowed others. The applicant canceled several claims and Reporter's Statement of the Case requested a reconsideration of others, whereupon the application was allowed. On April 3, 1923, patent #1450653 was issued on said application. This is the patent in suit. A copy of the file-wrapper and contents relating to the patent in suit, defendant's exhibit 7, is by reference made a part of this finding. 20. The patent in suit to Swebilius, #1450653, relates to the synchronization of machine guns with respect to propellers of airplanes. As disclosed in the inserted drawings, figs. 1, 2, and 4, a machine gun receiver has a breech bolt mechanism in which a breech bolt is mounted for sliding reciprocating movement, the bolt being bored longitudinally to receive the firing pin 4, fig. 2, which is normally urged forward by a spring 5 housed within the firing pin. As shown in fig. 1, a sear 11 is mounted to slide vertically in grooves formed on the rear face of the breech bolt. The lower end of this sear is so shaped as to engage a shoulder or projection 9 on the underside of the firing pin at its rear end in such manner as to hold the same in its retracted position. A cocking lever 8 is mounted on the breech bolt and extends upwardly therefrom. The upper portion of sear 11 is formed with upwardly faced cam surfaces 15, fig. 4, and a slide member 17, figs. 2 and 4, transversely inserted through a slot in the rear surfaces of the bolts, is adapted for a directional movement at right angle to the movement of sear 11. The cam surfaces 15, fig. 4, of sear 11 are engaged by complemental cam surfaces, 17a, fig. 4, formed on the slide 17 so that when the slide 17 moves transversely the sear 11, fig. 1, would be depressed, thereby releasing the firing pin 4. A trigger motor is mounted on one side of the receiver plates and cooperates with a triangularly formed trigger member 32, fig. 2, mounted on a pin 21a, fig. 2, in the trigger motor housing. A lug or member 28, fig. 2, is pivoted in the forward end of the triangularly formed trigger member 32, the inner end of which lug projects through a slot in the side plate of the receiver. When the breech bolt is in its breeched or locked position, this lug is in line with the sear slide 17 and will act to contact the |