EACOMBE, Circuit Judge.
[1] Judge Mayer has quoted quite fully from the patents and has set forth the eight claims involved; it will not be necessary to restate them here. Van Kannel was apparently a pioneer in the art of “revolving” doors, as distinguished from swinging doors. The revolving door has a series of radiating wings which rotate in a casing; the wings fit snugly in the casing, so as effectually to prevent the entrance of wind, rain, snow, or dust, either when the door is closed or when persons are passing through it. It is noiseless, and cannot be blown open by the wind, as the wind pressure is equal on both sides of the center of motion. It can be moved without noticeable resistance, as it requires no springs or weights to restore it to its closed position or any bumpers to prevent slamming. At it moves in but one direction, there is no possibility of collision when persons are passing both in and out at the same time. These features are all disclosed in an early patent to Van Kannel, No. 387,571, dated August 7, 1888, which has long since expired. That patent also1 provides for hinging one or more of the wings at a point near the central part, so that said wings can be thrown back against the fixed wing, thereby providing a clear opening through the structure to permit the carrying of a long object, like a ladder, in or out through the same, and also to provide for the circulation of air in the event of the occurrence of a suddenly warm day in the spring of fall, after the solid wings have been applied to the door.
There was one difficulty inherent in this structure: It could not move if pressure from one direction were applied simultaneously on both sides of the center of motion. That is the reason no gust of wind could blow it open. In the event, however, of a panic occurring within the building, followed by a rush to the door, pressure would be applied outwards on both sides of the center of motion, the door would not revolve, and egress from the room through the doorway would be blocked. This obvious danger connected with the- use of revolving doors was not overlooked by Van Kannel, who in his 1888 patent undertook to avoid it by making his door and casing independent of the building, being mounted on wheels and held in the doorway by hooks or catches of light structure which would give way under abnormal pressure, allowing door, casing, and the front files of the crowd to roll out into the street together.
The first patent sued upon here discloses an improved method of adapting the door to a condition of panic. Each wing is hinged near the center of rotation and held normally in such relation to the rest of the wing that, when abnormal pressure comes, the holding parts will disengage and the hinged portions will swing forward, making a wide and unobstructed passage on each side of the central post on which the wings revolve. We fully concur with Judge Mayer in the conclusion that this patent (656,062) discloses patentable invention. The panic device of 1888 was crude and manifestly dangerous; the defect of the revolvingdoor (jamming when a panic rush came against it) was obvious ; during the 12 ensuing years patents for various improvements were taken out by Van Kannel and others, but none of them remedied the difficulty, which it must be presumed they were all trying to do, be*747cause, until that was remedied, the revolving door system was seriously handicapped. It is unnecessary to add anything to Judge Mayer’s discussion of this patent and its claims. Defendant is clearly wrong in his contention that the device actually shown in this patent of 1900 is not automatic or self-releasing, as the claims describe it, but is a “weak or breakable device merely.” When the abnormal pressure comes, nothing breaks, the holding devices are merely pulled or pushed out of engagement with other parts, and restoration of conditions is accomplished merely by re-engaging them, uninjured by temporary disengagement.
[2] The second patent in suit is evidently an attempt to extend^ the monopoly of the earlier patent by changing the names of the_ various elements. The District Judge found that its broader claims involved merely a change of location of holding devices, which did not rise to the dignity of invention. The narrower claims (13 and 14) disclose nothing but a combination of old elements which would be evident to an ordinary mechanic.
The decree is modified, so as to reverse as to these two claims and affirm as to all the others. No costs of this appeal to either side, as neither has prevailed as to all the claims in controversy.