The origin of the very first explosive, black powder, which was a mixture of saltpeter or potassium nitrate, sulfur and carbon (charcoal), is not known with any degree of certainty. General opinion has it that it was first discovered in China during the tenth century, but it was only used in fireworks displays and to send up signals as in modern day flares. It was not used to propel weapons, or for other military purposes. The Arabs and a medieval scholar have also laid claim to its discovery.
By the year 1300 the Arabs had devised the first real gun and there is evidence that they had known about the properties of black powder for hundreds of years before this. Their gun was made from a wide bamboo tube which was reinforced with iron bands and was charged with black powder which fired an arrow.
There are also written records from 1242, by the medieval scholar Roger Bacon, in which he wrote down detailed instructions for making black powder. However it is a known fact that Bacon was able to read and translate Arabic script, so it is possible that this is how he knew the composition of the powder and what it could do.
Italian chemist, Ascanio Sobrero, discovered nitro-glycerin, a chemical explosive, in 1846. This powerful explosive was only really something that was experimented with in laboratories until the Swiss inventor Immanuel Nobel and his son Alfred started to explore its possibility as a commercial product about fifteen years later. (Yes, ironically enough that is the same Nobel of peace prize fame, if you were wondering.)
In 1865, Alfred Nobel made a major advance in the science of explosives when he invented the blasting cap which is a device for detonating explosives and this was considered to be the greatest innovation in this field since the original discovery of black powder.
Nobel also invented dynamite, in 1867. His work was based on his discovery that kieselguhr, a very porous silica based kind of earth, would soak up and absorb very large quantities of nitro-glycerine. This made the explosives much more stable and safer to handle than using nitro-glycerine by itself.
All these amazing discoveries took almost 900 years to get to the stage where explosives could be transported around and used for things like rock blasting and mining purposes. The discovery made a massive difference to road building, the newly burgeoning railway systems and the mining industry all over the world.
Development of explosive devices and the way they are used has taken a far more sinister turn since 1955 with the advent of nitro-glycerine and even more complex and sophisticated forms of explosive like Semtex, nitrate fuel oil mixtures and ammonium nitrate based water gels, which are now in use in weaponry.
