Furnaces in the early days were set practically flat on the ground and their operating level was the general ground level, it being possible to walk about them without the use of stairs of any kind. But the tendency has steadily been to raise the furnace proper higher and higher above the ground level,1 primarily to permit placing ladle cars under the spouts delivering the iron and cinder from the cast house. Many low-built furnaces were equipped for handling cinder in hot pots by digging deep pits for the ladle tracks and running down into these on a sharp grade. This is a way out of the difficulties which arise by not having sufficient height but it is an exceedingly poor one, because it increases enormously the difficulty of pulling the cars out of the pit and of handling them in it. Moreover, if a "mess" occurs, as it occasionally does in spite of the best management, the cinder and often the iron flow into the pit, or fill up the ladles, and then overflow them, running down into the pit itself and making in some cases a pool two or three feet deep of molten iron and cinder at the bottom of a deep pit with masonry walls. The task of removing this, which is absolutely necessary before the furnace can be put back into operation, is bad enough to contemplate but much worse to experience, while the expense of the delay and repairs to tracks are very heavy.

Even where the pig iron is handled cold, by hand, it is extremely desirable to have the cast house set well above the level of the iron shipping tracks, very frequently transfer trucks are used in taking the iron from the cast house to the iron scales or the storage yard, or to the broad-gauge cars for final shipment, it is of course important to be able to drop the iron down to these transfer cars and also to drop it again to the standard-gauge cars. All of these considerations have demanded that furnaces be set higher and higher with the result that the hearth level at modern furnace plants is from 15 to 20 feet above the ground level.

The tracks serving the cast house and the cinder runners instead of being of the "dead end" variety as they must be if they are in pits, are, if possible, always made through tracks on the ground level, so that if there be an obstruction in one direction the liquid iron and cinder may be hauled away in the other.

It is probably advisable to go even a step further than this and to have the level of these tracks where the ladles stand on them raised a little above the level of the surrounding territory so that in case of a breakout or other accident the runaway iron and cinder instead of forming a pool on top of the tracks, to their complete destruction, may run down hill off of them.