A Visit to a Famous Furnace.
Some time ago when I was staying at Lebanon, Pa., I had the pleasure of visiting the Colebrook furnace. This is what is called a "blast furnace," because the draught for the fires is made artificially by the forcing in of a strong current of air. Much iron is smelted in that region, the ore coming from the famous Cornwall ore hills near by. The Colebrook produces about 175 tons of iron daily.
It was on a hazy June morning that our party took a new trolley-car that had been running only a few days, and after riding a short distance into the country, alighted quite near the furnace, which seemed to be composed of a few gray stone buildings, and several high red stacks. After passing over some waste land and a little brook we came to the office, where we inquired whether we had better have a guide to show us around, or go by ourselves. A young gentleman who belonged to the establishment offered to go with us. He was very kind, explaining everything, and was never tired of answering questions.
They cast twice a day; there are two furnaces, one used for the casting in the morning, and the other in the afternoon. We began our tour of inspection by visiting one of the furnaces. Of course we found it quite warm near it. When they wished to see whether the fire was burning all right, they used to have to open large doors, but now there are pipes with holes and some kind of glass in them that they can look into and see the fire. The gas that is thrown off by the burning of the coke and ore is returned to the furnace and used as fuel, hence there is a great saving of coke.
Next we went to see the "roasters." The ore has to be roasted before it is put into the furnace, to get as much sulphur out of it as possible. After it comes out of a "roaster," instead of it being of a gray color, most of it has a reddish tint. After being roasted and before being put into the furnace limestone is added. There are over twenty roasters. The next place we visited was called the "tunnel head"—in plain language, the top of furnace number two. We went up in an open elevator that quite took one's breath away. At the top of the furnace is the "bell and hopper," which is a circular opening with a bell-shaped cover which keeps in the gas. In the opening the ore and coke are put in, then the bell is let down, and the fuel and ore is dropped into the furnace.
After we came down from the tunnel head it was suggested that we should visit the "drawing room." I wondered whether a furnace's drawing-room was like one in a private house, but when we arrived there I found that it was quite different. Instead of tables and chairs it contained four engines, each having two fly-wheels about twenty-two feet in diameter. These engines made the draught to "draw" the fires, so the place they were in was called the drawing-room.
To see the "casting" we had some time to wait after we had completed our tour, having been almost everywhere, except on top of the roasters. A railroad comes right to the furnace, and while we were waiting a train of eight cars containing coke passed by.
At last it was almost ten o'clock, so we drew near the building where they were to cast. We could hear and see them opening the furnace-door to let out the ore and cinders. A locomotive and several "cinder-tubs," the tubs looking like large iron pots, were on a track beside the building, the front tub being under a trough where the cinders came out. When one tub was full, a man would hold the cinders back, and the engine would go forward until another tub was under the trough.
Afterward the contents of the tubs were dumped on the bank of the stream near the furnace. The iron and the cinders can easily be separated, as the iron is heavier and goes to the bottom.
The moulds for the iron are made on the floor of the building with sand. The pig-iron is made in small troughs. In order to keep the metal flowing in the large troughs, men have to loosen it constantly with long poles. The iron as it comes from the furnace looks like melted gold.
Grant Knauff.
Flushing.