28 Responses to The Real Origin of Viking Raids. 1  Well done! 2  Thank you for this article. 3  The shutting of the ancient trade routes to Rome and the East by the Holy Roman Empire was the principle reason that the Rus trade routes down the Volga were established. 4  Pingback: Daily Stuff 5-20-13 MjÃ¶lnir | Ancient Light's Daily Stuff.
By Anne Marie Helmenstine, Ph.D. Gunpowder or black powder is of great historical importance in chemistry. Although it can explode, its principal use is as a propellant. Gunpowder was invented by Chinese alchemists in the 9th century.Originally, it was made by mixing elemental sulfur, charcoal, and saltpeter (potassium nitrate).y Anne Marie Helmenstine, Ph.D. Gunpowder or black powder is of great historical importance in chemistry. Although it can explode, its principal use is as a propellant. Gunpowder was invented by Chinese alchemists in the 9th century.
The development of the stationary steam engine was an important element of the Industrial Revolution; however, during the early period of the Industrial Revolution, the majority of industrial power was supplied by water and wind. In Britain by 1800 an estimated 10,000 horsepower was being supplied by steam.