May Wirth  May Wirth (6 June 189418 October 1978) was an Australian circus and vaudeville performer famous for her ability to do somersaults forwards and backwards on a running horse. She was inducted to the Circus Hall of Fame as a bareback rider in 1963. Wirth was born in Bundaberg, Queensland on 6 June 1894. She was the daughter of a Mauritian circus artist, John Edward Zinga (Despoges) and Dezeppo Marie, née Beaumont. Wirth was adopted in 1901 by Mary Wirth an equestrienne and the sister of circus proprietors Philip and George Wirth. Wirth performed with the Barnum and Bailey circus in the United States, and was the star of Wirth's Circus in 1916 as the "greatest bareback riding star"  May Wirth and her stepsister appeared on an Australia Post commemorative postage stamp issued on 13 March 1997 commemorating 150 years of circus in Australia.