John Kay (spinning frame) a spinning machine embodying the ideas which they had been developing. Arkwright patented it 1769 without mentioning Kay, his "workman". Kay learned of this patent from another Nottingham inventor, James Hargreaves, and told Hargreaves that it was he, Kay, who was the real inventor. Arkwright accused Kay of revealing the design to Hargreaves, and the two fell out. Kay left Arkwright's Nottingham house, where he had been living, ending their relationship. Kay subsequently accused Arkwright of stealing his work tools, and Arkwright made a counter-charge . The spinning machine as constructed in Nottingham by Kay and Arkwright was powered by
Cotton-spinning machinery rival machine, the throstle frame or ring frame was a continuous process, where the roving was drawn twisted and wrapped in one action. The spinning mule became self-acting (automatic) in 1830s. The mule was the most common spinning machine from 1790 until about 1900, but was still used for fine yarns until the 1960s. A cotton mill in 1890 would contain over 60 mules, each with 1320 spindles. Between the years 1824 and 1830 Richard Roberts invented a mechanism that rendered all parts of the mule self-acting, regulating the rotation of the spindles during the inward run of the carriage.