Multiple roll developing apparatus

An apparatus for applying toner particles to a photoconductive surface having multiple magnetic brushes each of which consists essentially of a magnetic inner shaft and a nonmagnetizeable outer sleeve, with both the sleeve and the inner shaft of each brush being capable of independent rotation. The apparatus uses an adjustably mounted doctor blade to apply toner particles to one of the brushes. The rotation of the inner shafts and sleeves of the brushes, the spacings between the brushes, as well as the magnetic attraction between the brushes affords the transfer of toner from this first brush to the other brushes. Following the transfer of toner, each brush is able to apply toner to the photoconductive surface.