spinning machine constructed in Nottingham by Kay and Arkwright was powered by horses, and apparently was not commercially viable. But it did prove the feasibility of the new machine, known as a "spinning frame". Arkwright was thereby able to finance a more elaborate mill using water power, built in 1771 on the River Derwent at Cromford. The new machine, called a "water frame", would revolutionize the textile manufacturing industry and enrich Arkwright and his partners – but not Kay. Disputes over patents Arkwright obtained a "Grand Patent" covering the spinning frame and other inventions in 1775. Subsequent infringements by mill-owners led him to take legal action to assert his rights. A series of trials began in 1781, and in the last of them (1785), Arkwright's claims as an inventor were called into question, Highs, Kay and Kay's wife Sarah all testifying that Arkwright had stolen High's invention of the rollers "by the medium of Mr Kay". Subsequently it was variously claimed that Arkwright had envisaged the design before meeting Kay, that Kay had stolen High's ideas, or that Kay conceived the machine as well as building it. The case did not settle the question of authorship, but was notable for clarifications of patent law in the instructions given by the judge to the jury: they must find the patent null, regardless of authorship, if they considered it insufficiently novel, or if Arkwright had failed to adequately specify the technology in the patent documents. Presumably on these grounds, the jury set aside the patents—a loss for Arkwright, as well as for Highs and Kay. References Notes Citations Bibliography People of the Industrial Revolution English inventors English clockmakers Textile workers Year of birth missing Year of death missing Cotton industry in England People from Warrington