Chevreul was a determined enemy of charlatanism in every form, and a complete sceptic as to the "scientific" psychical research or spiritualism which had begun in his time. His research on the "magic pendulum", Dowsing rods and table-turning is revolutionary. In an open letter to André-Marie Ampère in 1833, and his 1854 paper "De la baguette", Chevreul explains how human muscular reactions, totally involuntary and subconscious, are responsible for seemingly magical movements. In the end, Chevreul discovered that once a person holding divining rods/magic pendulum became aware of the brain's reaction, the movements stopped and could not be willingly reproduced. His was one of the earliest explanations of the ideomotor effect.