Chimney stacks once lined many city skylines across America and Europe and became extremely popular during the 1800’s Industrial Revolution, which began the shift from hand made products to machine made.  Also known as flue-gas stacks, the chimneys are used as an exhaust method for industrial furnaces, steam boilers, and other similar heat and smoke producers.  The concept of the flue-gas stack was developed in the mid-1600s, before the concept expanded some 200 years later.