When I arrived the Guild members (www.massart.edu/ironguild) had their equipment set up and fired up with a roaring wood fire. Wood is used to start the process because it is very inexpensive.
Text in italics is provided by Laurie Carman, webmaster of the Iron Guild website.
The vessel used in this process is called a cupola. That is the black barrel like object sitting on the stand in the center of the photo. At the right can be seen a flexible hose which is connected to a electric blower that provides air to the fire. The cupola is lined with a fire and heat resistant material called refractory clay which has to be replaced periodically. The spout at the bottom of the cupola is where the molten iron will come pouring out into a carrier called a crucible.
You CAN try this at home kids but it can be very dangerous and must be treated with utmost respect. There is a lot of good (and some not so good) information on the web on the subject of casting, do your research carefully and if at all possible enlist the assistance of someone who has experience work with molten metal.