The world's second and third grain elevators were built in Toledo, Ohio, and Brooklyn, New York, in 1847. These fledgling American cities were connected through an emerging international grain trade of unprecedented proportions. Grain shipments from farms in Ohio were loaded onto ships by elevators at Toledo; these ships were unloaded by elevators at Buffalo that shipped their grain to canal boats (and, later, rail cars), which were unloaded by elevators in Brooklyn, where the grain was either distributed to East Coast flour mills or loaded for further shipment to England, the Netherlands, or Germany. This eastern flow of grain, though, was matched by an equally important flow of people and capital in the opposite direction, that is, from east to west. Because of the money to be made in grain production, and of course, because of the existence of an all-water route to get there, increasing numbers of immigrants in Brooklyn came to Ohio, Indiana, and Illinois to become farmers. More farmers meant more prairies turned into farmlands, which in turn meant increased grain production, which of course meant that more grain elevators would have to be built in places such as Toledo, Buffalo, and Brooklyn (and Cleveland, Chicago, and Duluth). Through this loop of productivity set in motion by the invention of the grain elevator, the United States became a major international producer of wheat, corn, and oats.