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PATENT FOR MANUFACTURE OF IRON.--VINTON VS. HAMILTON et al. The bill of complaint alleged that the defendants were infringing certain letters patent, dated October 14, 187:3, granted to the complainant, John J. Vinton, for an improvement in the manufacture of iron from furnace slag, and prayed for an injunction to restrain them fDm further infringement and for damages and an account of profits. The answer of the defendants denied that Vinton was the original or first inventor or discoverer of the improvement in the manufacture of iron from furnace slag or from the slag of blast or smelting furnaces, set out in his patent, and denied infringement. Upon final hearing in the Circuit Court the bill was dismissed because the process described in complainant's letters patent was known and in common use before the complainant's application for his letters patent, and the same were therefore null and void. The complainants, therefore, appealed the case to this court. Mr. Justice Woods delivered the opinion of the court. It is matter of general knowledge that pig iron is made from iron ore in a blast or smelting furnace; that to secure this product the furnace is charged, first, with a layer of coke or charcoal, then with a layer of iron ore mixed with broken limestone, and so on in alternate layers until the proper quantity of these materials is placed in the furnace. The fuel is then ignited, and for the purpose of increasing the heat, streams of air are forced into the furnace by means of blast-pipes, the nozzles of which, called " tuj'eres," are-inserted in openings in the walls of the furnace, usually from four to six feet ab;)ve its bottom. The limestone is used marely as a flux. The ore under this process undergoes a chemical change, and iron is formed and sinks in a molten state to the bottom of the hearth, by which is meant not only the bottom of tlie furnace, but its sides as high up as the foot of the boshes. The refuse left after the melted iron has dropped into the hearth is also in a molten state, and, being lighter than the iron, fioats on its top. This is indifferently called "cinder and slag." About three or four times in every twenty-four hours the melted iron is drawn from the furnace. This is accomplished in the following manner: The furnace is constructed with two holes, one called the "iron "and the other the " cinder" notch. The iron-notch is made at the bottom of the hearth. The cinder-notch is higher up the side of the furnace, just below the level of the tuyeres--so high that the cinder can be drawn through it without letting off the molten iron. These holes are kept habitually closed with clay or other similar material. At frequent intervals, and always just before drawing off the molten iron, or making a " cast," as the ironmongers call it, the cinder notch is opened and the cinder or slag is allowed to escape, and is carried away from the furnace in a trough made of moistened sand. The cinder notch is then closed and the iron notch is opened, and the molten iron is drawn off through a sand trough, and conducted into moulds made in sand beds, called the " sow and pigs," where it is allowed to cool. The result is the pig iron of commerce. In the meantime the furnace is supplied with constant charges of fuel and ore mixed with limestone in alternate layers, dumped in from the top, and this process is kept up without cessation for months arid sometimes for years. The sand trough which connects the pig-beds with the iron notch is usually larger and deeper, but more elevated than the sow or general gutter which condu!ts the iron into the moulds or grooves in the pig-beds. When the metal is first let into the trough it accumulates so as to fill it nearly to the brim. As the flow from the iron notch decreases, the iron and a small quantity of cinder or slag, which has been chilled by coming in contact with the cold surface of the trough, adhere to its sides and bottom. When the molten iron on the hearth is about exhausted the blast is increased, and the material left on the hearth is blown out through the iron notch into the sand trough. This also cools in the trough, and thus is formed what are known as "trough-runners," consisting of iron and slag, which have been forced through the iron notch by letting on the blast, as just mentioned. A cupola furnace is one used for melting pig iron for the purpose of casting it into useful forms and articles. It con. stitutes part of the equipment of a foundry. In shape it is generally a hollow cylinder. The iron is melted by substantially the same process as the ore in a blast furnace. The cupola furnace has an iron notch, but no cinder notch, because there is generally so little cinder or slag in pig iron as to render such an opening unnecessary. In order to reach the merits of the controversy it is necessary to obtain a definite idea of what, if anything, the appellants are entitled to under their patent. The specifications are ambiguous in respect to the particular kind of slag which is to be used in the process therein described--that is to say, whether it is the slag drawn off through the cinder notch or the runners which are left in the trough through which the molten iron is discharged from the iron notch of a blast furnace. It appears, however, from the evidence that the use of the latter only is contemplated, the former containing such a very inconsiderable quantity of iron as to be valueless. We observe, in the first place, that the patent cannot be held to cover the discovery that the slag which is to be used in the process described in the specifications contains so large a percentage of good metallic iron that it can be profitably extracted by again smelting it. The evidence shows beyond controversy that for many years before September 18, 1878 (the earliest date assigned to the discovery or invention of the complainant), it had been well and generally known that the trough runners contained a large proportion of metallic iron, and they were broken up and resmelted in blast furnaces. They were thrown into the furnace with scrap iron and iron ore, and smelted in the same manner. It was formerly a notion among old-fashioned f urnacemen that the use of this material injured the furnace and deteriorated the quality of the iron produced; but this conceit had been exploded long before the date of appeUant's patent, and the runners and other heavy slag were used habitually in many blast furnaces, as above stated. Secondly. The appellant cannot claim as any part of his invention the use of a cupola furnace for the purpose of re-smelting,trough runners and heavy slag. The evidence in the record shows that as early as the year 1844, at the Jack-ion Furnace, in Venango county, Pennsylvania, which was i blast furnace, a cupola furnace was erected and used for ;he purpose of smelting heavy slag, from which was manu-ractured plow points and hollow ware, such as skillets, pots, md Dutch ovens. Sometimes the product was made into pig iron. This cupola furnace was thus used for three or four years. The fact of such use was public; no effort was made to keep it secret, and it was known in the language of ;he witnesses, "all around the furnace." It is therefore abundantly shown in the record that before ;he date of complainant's patent or of his invention the smelting of trough runners and other heavy slag in cupola 'urnaces was practiced and well known. Thirdly. The method of making slag granulous or spongy, jy passing water or air through it when in a molten state, is lot new, nor is it claimed to be new. Besides, there is no evidence that this process is used by the appellees. Fourthly. The method of charging the cupola furnace md of smelting the slag as described in the specification 3f appellant's patent is as old as the art of making pig iron, except, perhaps, the sprinkling of scale or black oxide of ron on the top of the coke, and this is not done by the appellees. Fifthly. The appellant does not claim that his invention : jovers a cupola furnace. A review of the case shows, there-'ore, that appellant did not first discover the value of fur-lace runners or heavy slag for resmelting; that he was not ,he first tosmelt them and use them for running into pigs or castings, either in a blastfurnace or a cupola furnace, and ,hat there is nothing new in his process of smelting which is ised by the appellees. All therefore that is left for his invention to cover, and which appellant can claim as infringed by the appellees, is j ,he employment of a cinder notch or hole in a cupola furnace ; 0 draw off the cinder when the furnace is employed in smelting furnace-runners or heavy slag. But if the testimony 3f unimpeaclied and uncontradicted witnesses is to be be-ieved, as early as June, 1872, at Beaver Falls, Pennsylvania, 1 cinder notch was used by the Beaver Falls Co-operative Association in a cupola furnace when employed in smelting 'urnace-runners. But even if the application of a cinder notch to a cupola furnace was first made by the appellant, the question re-nains whether, standing alone, it implies invention and is patentable. We think this question must be answered in the negative. S'either a cupola furnace nor a cinder notch is new. The use 3f a cinder notch for drawing off cinders from a blast furnace s as old as blast furnaces themselves. The function which ,he cinder-notch performs in the prfcess covered by the ippellant's invention is precisely the same for which it is ised in a blast furnace. In smelting slag in a cupola-furnace t was found that the molten cinder accumulated and floated )n the top of the molten iron. The application to a cupola-'urnace, for the purpose of drawing oft the cinder, of the :inder notch used in the blastfurnace to accomplish the same end, would occur to any practical man. When applied 0 a cupola furnace the same function was performed in the iaoae way by the same means. In making this application here was no invention. {Pea,rce vs. MijJford, 102 U. S., 112.) We are of opinion, therefore, that the application of a cinder notch to a cupola furnace for the purpose designated is neither patentable nor new, and that all the other parts of the process and appliances covered by appellant's patent were old and well known long before tlie date of his alleged invention and the patent therefor. The complainant was not the first inventor, either in fact or in law, of the discovery or invention described in his letters patent. The patent is therefore void, and the decree of the circuit court dismissing the bill was right and must be affirmed.
