Nitroglycerin processing plant, explosives factory, Val Bormida, near Cengio, North West Italy, 1888. Nitroglycerin mixed with Kieselghur (a diatomaceous earth) to produce Dynamite. Patented by Alfred Nobel (1833-1896) in 1867, Dynamite a more stable high explosive than gunpowder and nitroclycernin, and quickly gained popularity for blasting in mining, tunnelling and quarrying. Because of the instablility of the materials used in its production, earth embankments separate each building and surround the whole complex. The roofs of the buildings were not fixed so that in the event of an explosion the blast would travel vertically rather than horizontally. From 'La Nature', Paris, 1888. Engraving.