The Birthing Furnace had the ability to create living genasi babies. It was believed that the Birthing Furnace produced more babes than the handful that emerged from it, but that, due to malfunctions, those with manifestations other than firesoul were consumed the by the forge's fires before they could crawl forth.
The Birthing Furnace could only be activated once per year by using a special key at the proper time.
The Birthing Furnace was used by members of the Dominion of the Burned to replenish their numbers by creating new genasi babies each year. As of 1479 DR, the owner of the Furnace's key was the leader of the Burned, Brindol.