 In 1881 Turpin proposed panclastites, a class of Sprengel explosives based on a mixture of a suitable fuel with dinitrogen tetroxide as an oxidizer.In 1885, based on research of Hermann Sprengel, Turpin patented the use of pressed and cast picric acid in blasting charges and artillery shells.In 1887 the French government adopted it under the name Melinite, with addition of gun cotton.