The Circuit Court found that the patent was invalid for lack of invention, and, after an examination of the record, we see no reason to disturb this finding. The important element of the combination of the claims, and the one which produced a real advance in the art, was the transfer of power from the e’enter to the periphery of the moving disk by means of the sprocket-wheel engaging in the apertures near the outer edge of the disk; but this was not new with the patentees. The other elements of the combination are old, and the combination itself, speaking broadly, is old, being differentiated from the prior art by the introduction of the hinged rod, with anti-friction wheels thereon, as a substitute for the devices of the prior aft used to produce similar results. This may be an improvement over the means previously adopted for giving uniform pressure to the disk ; but in view of the prior art, as disclosed by the record, and in view of the very obvious use of anti-friction wheels, in such environments, we are of tlie opinion that the adoption of the hinged rod of the patent did not involve invention. It was the work oí a mechanic familiar with the requirements of the art, and not of an inventor. The decree is affirmed.