Firebox

( Mach.) In locomotive-engines, the box (usually made of copper) into which the fire is placed. The outside is of iron, separated from the copper firebox by a space of about 3 inches all around for water. Fire - box door, the door opening into the fire-box, facing the locomotive tender, by which coke is supplied to the fire. Fire - box partition, in large fire-boxes a division is made in the box, into which water is admitted; this division is about the height of the fire-box door, and divides the fire into two parts in a locomotive-engine, thereby increasing the heating surface of the fire-box.Fire-box stays, deep strong iron stays bolted to the top of the copper fire-box, to enable it to resist the pre ure of the steam; round copper or iron stays are also used to connect the outside shell to the inside box, in the proportion of about one stay to every 4 square inches of flat surface.