At the time Halford's theories were fashionable and his flies commonplace, but Dunne noticed that they did not match the real flies he saw while fishing. He was one of the first writers to challenge the Halford school, developing new theories and a number of dry flies based on the translucence of a fly when seen from underneath in direct sunlight. In Dunne's flies the hooks were painted white to reflect light, bound in methodically coloured fibres and oiled to make the fibres more translucent.