The puddling furnace was improved by Henry Cort at Fontley in Hampshire in 1783–84 and patented in 1784. Cort added dampers to the chimney, avoiding some of the risk of overheating and 'burning' the iron. Cort's process consisted of stirring molten pig iron in a reverberatory furnace in an oxidising atmosphere, thus decarburising it. When the iron "came to nature", that is, to a pasty consistency, it was gathered into a puddled ball, shingled, and rolled (as described below). This application of grooved rollers to the rolling mill, to roll narrow bars, was also Cort's invention. Cort was successful in licensing this process and receiving revenue from it, even from ironworks like Cyfarthfa, where the earlier process had been invented previously by their neighbours at Dowlais. Cort is now generally regarded as the 'inventor' of puddling.