John Miller

John A. Miller (born August John Mueller; 1872 – June 24, 1941) was an American roller coaster designer and builder, inventor, and businessman. Miller patented over 100 key roller coaster components, and is widely considered the "father of the modern high-speed roller coaster." During his lifetime, he participated in the design of approximately 150 coasters and was a key business partner and mentor to other well-known roller coaster designers, Harry C. Baker and John C. Allen. Biography Early life Miller was born in Homewood, Illinois and worked as a coaster builder at a very early age. At the age of 19, he started working with La Marcus Thompson and went on to serve as Thompson's chief engineer. By 1911, he was working as a consultant to the Philadelphia Toboggan Company He also worked with noted designers Frederick Ingersoll and Fred and Josiah Pearce. Miller in 1910 designed a device that prevented cars from rolling backward down the lift hill in the event of pull chain breakage. It attached to the track and clicked onto the rungs of the chain. Known as the safety chain dog, or safety ratchet, it evolved into the device on the underside of cars that makes that distinctive sound of wooden coasters.