Dynamite is an explosive material made of nitroglycerin, sorbents (such as powdered shells or clay) and stabilizers. Dynamite was invented by Alfred Nobel and was the first safely manageable explosive stronger than black powder. Nobel obtained patents for his invention in England on May 7, 1867, in Sweden on October 19, 1867. After its introduction, dynamite rapidly gained wide-scale use as a safe alternative to black powder and nitroglycerin. Nobel tightly controlled the patents, and unlicensed duplicating companies were quickly shut down. However, a few American businessmen got around the patent by using a slightly different formula. Nobel originally sold dynamite as "Nobel's Blasting Powder" but decided to change the name to dynamite, from the Ancient Greek word δύναμις (dýnamis), meaning "power". An industrialist, engineer, and inventor, Alfred Nobel's father, Immanuel Nobel, built bridges and buildings in Stockholm. His construction work inspired him to research new methods of blasting rock. Immanuel's work with explosives later on inspired Alfred to make explosives safer and more effective. Today dynamite is mainly used in the mining, quarrying, construction, and demolition industries.