Nitroglycerin (NG), also known as nitroglycerine, (UK Spelling), trinitroglycerin, trinitroglycerine and glyceryl trinitrate is a chemical compound. It is a heavy, colorless, oily, explosive liquid obtained by nitrating glycerol. Since the 1860s it has been used as an active ingredient in the manufacture of explosives, specifically dynamite and as such is employed in the construction and demolition industries. Similarly, since the 1880s, it has been used by the military as an active ingredient and a gellatinizer for nitrocellulose in some solid propellants such as Cordite and Ballistite. Nitroglycerin is also used medically as a vasodilator to treat heart conditions such as angina and chronic heart failure.