Mesmerism is a concept developed by the German doctor Franz Friedrich Anton 'F.A.' Mesmer (1734-1815). Mesmerism, or animal magnetism, was a natural energy source that was transferred between organisms and objects. Mesmerism originally was referring to the animal magnetism itself but mesmerism is now used to refer to the hypnosis brought on by animal magnetism. This concept was influential from the late 1700s to the late 1800s even drawing the attention of Louis XVI, the king of France.