Phosphorus is a non-metal that sits just below nitrogen in group 15 of the periodic table. This ELEMENT exists in several forms, of which white and red are the best known.White phosphorus is definitely the more exciting of the two. As it glows in the dark, is dangerously flammable in the air above 30 degrees, and is a deadly poison. Red phosphorus however has none of these fascinating properties.So where did it all begin? Phosphorus was first made by Hennig Brandt in Hamburg in Germany in 1669. When he evaporated urine and heated the residue until it was red hot. Glowing phosphorus vapour came off and he condensed it under water. And for more than 100 years most phosphorus was made this way. This was until people realised that bone was a great source of phosphorus. Bone can be dissolved in sulfuric acid to form phosphoric acid, which is then heated with charcoal to form white phosphorus.White phosphorus has found a range of rather nasty applications in warfare. It was used in the 20th century in TRACER bullets, fire bombs, and smoke grenades. The scattering of phosphorus fire bombs over cities in World War II caused widespread DEATH and destruction. In July 1943, Hamburg was subject to several air raids in which 25,000 phosphorus bombs were dropped over vast areas of the city. This is rather ironically considering where phosphorus was first made.Another group of warfare agents based on phosphorus are nerve gases such as sarin. Sarin is a fluorinated phosphonate that was used by Iraq against Iran in the early to mid-1980s. And was also released in a Tokyo subway in 1995, killing 12 people and harming nearly a thousand others.White phosphorus has also found a wide range of other uses. One of these was in phosphorus matches that were first sold in Stockton-on-Tees in the UK in 1827. This created a whole new industry of cheap lights - but at a terrible cost. Breathing in phosphorus vapour led to the industrial disease phossy JAW, which slowly ate away the jaw bone. This condition particularly afflicted the girls who made phosphorus matches. So these were eventually banned in the early 1900s and were replaced by MODERN matches which use either phosphorus sulfide or red phosphorus.As well as in matches, today phosphorus has found other uses in lighting. Magnesium phosphide is the basis of self-igniting warning flares used at sea. When it reacts with water it forms the spontaneously flammable gas, diphosphine which triggers the lighting of the flare.Super pure phosphorus is also used to make light emitting diodes. These LEDs contain metal phosphides such as those of gallium and indium.