William John Warner (also known as Count Louis Hamon according to some sources), popularly known as Cheiro (November 1, 1866 - October 8, 1936), was an Irish astrologer and colorful occult figure of the early 20th century. His sobriquet, Cheiro, derives from the word cheiromancy, meaning palmistry. He was a self-described clairvoyant who said he learned palmistry, astrology, and Chaldean numerology in India. He was celebrated for using these forms of divination to make personal predictions for famous clients and to foresee world events.