Who patented a steam engine that produced continuous rotary motion?

James Watt patented a steam engine that produced continuous rotary motion because his improvements to the existing design were groundbreaking. Watt's engine incorporated a separate condenser, which greatly enhanced its efficiency by allowing for the continuous use of steam without having to heat and cool the cylinder with every stroke. This innovation minimized energy waste and made the engine more practical for various applications, revolutionizing industries such as mining, manufacturing, and transportation. Watt's patent protected his invention, ensuring his significant contribution to the development of steam power and its widespread adoption.