Guillaume Dubuc (1764-1837), a French chemist and pharmacist who carried important research about opium, vegetable principles (jalap, aloe, ipecacuanha, squill, buckthorn, belladonna, madder, and pokeweed), distillation of seawater, active carbon, the apple aphid, and the use of calcium chloride for food conservation and as manure. He proved that commercial opium was not the pure extract or poppy juice and that the Levant opium was not the only extract prepared from white poppies. He defined the correct composition of the plant extracts described in the French Code, the procedure for identifying adulterants in madder, and suggested the use of the juice of pokeweed as a textile dye. Examined a large number of vegetables as possible sources of active carbon and classified them according to their water absorption capacity. He suggested using the apple aphid as replacement of cochineal. He proved that a dilute calcium chloride solution was appropriate for conserving meat and vegetables and also an active material for increasing the growth of plants
