 In the bridgeloft the materials were probably weighed and, maybe, mixed before being charged into the furnace.When the furnace was fired the steam engine blower, now gone, forced a continuous blast of air into the bottom of the furnace in order to make the coke burn brighter and raise the temperature inside high enough to melt the iron (1,538 °C, 2,800 °F).The hot gases exhausted from the low chimney at the top of the furnace.