Rowell v. Lindsay, 113 U.S. 97 (1885), was a bill brought by the appellants, John S. Rowell and Ira Rowell, the plaintiffs in the circuit court. The bill was in equity against Edmund J. Lindsay and William Lindsay, the appellees, to restrain the infringement of reissued letters patent No. 2,909, dated March 31, 1868, granted to the plaintiffs for 'a new and improved cultivator. The answer of the defendants, among other defenses, denied infringement of the letters patent. The plaintiffs contended that infringement of their letters patent was made out by the evidence, which tended to show that the defendants constructed and sold seeding-machines made according to the specification of letters patent granted to John H. Thomas and Joseph W. Thomas, dated June 30, 1874, for 'an improvement in seeding-machines.' This invention related to the drag-bars and shovel standards of broad cast seeders, and consisted mainly in the manner of attaching the standards to the drag-bar. Upon final hearing upon the pleadings and proofs the circuit court dismissed the bill, and the plaintiffs appealed. The evidence showed that the shanks or standards of plows, cultivators, and seeding machines have been used in a great variety of forms. In some, the upper end of the brace entered the beam in the rear, and in others, in front of the shank. In some, the upper end of the shank and the brace were so formed and united as to present an elliptical figure. Many, perhaps the majority, were without braces. In some, the upper end of the shank was made with a head in the form of an elliptical or circular plate, called an enlarged head. This performed the function of a brace. The patent of the plaintiffs stood on narrow ground, and to sustain it, it must be construed as to confine it substantially to the form described in the specification. The patent of the plaintiffs was for a combination only. None of the separate elements which the combination was composed are claimed as the invention of the patentee; therefore none of them, standing alone, are included in the monopoly of the patent. As was said by Mr. Justice BRADLEY in the case of The Corn-Planter Patent, 23 Wall. 224: 'When a patentee, after describing a machine, claims as his invention a certain combination of elements, or a certain device, or part of the machine, this is an implied declaration-as conclusive,