Grain elevators are builings or complexes of buildings for storage and shipment of grain. They were invented in 1842 in Buffalo, New York by Joseph Dart, who first developed a steam-powered mechanism, called a marine leg, for scooping grain out of the hulls of ships directly into storage silos. Older grain elevators and bins often were constructed of framed or cribbed wood and were prone to fire. Grain elevator bins, tanks and silos are now usually constructed of steel or reinforced concrete. Bucket elevators are used to lift grain to a distributor or consignor where it flows by gravity through spouts or conveyors and into one of a number of bins, silos or tanks in a facility. When desired, the elevator's silos, bins and tanks are then emptied by gravity flow, sweep augers and conveyors. As grain is emptied from the elevator's bins, tanks and silos it is conveyed, blended and weighted into trucks, railroad cars, or barges and shipped to end users of grains (mills, ethanol plants, etc.)