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The history of matches reflects a series of attempts to create a safer, more reliable means of producing fire on demand. Early friction matches, developed in the early nineteenth century, ignited unpredictably and often ejected burning fragments, making them hazardous to handle. Their chemical composition, which included white phosphorus, also caused severe illness among factory workers exposed to fumes during manufacturing. The invention of the safety match later in the century addressed both problems by separating the ignition chemicals: one compound was placed on the match head and a second on the striking surface, so that a flame could only be produced when the two were brought together deliberately. This division of chemicals significantly reduced accidental fires and worker poisoning alike.