THE MACINTYRE BLAST FURNACE
by Thomas Joyce and John Oxenford
This is the third in a series of articles about our historic blast furnace. The authors continue to explore the great problems the original owners faced. At this point in the series, the authors and editor gratefully acknowledge the magnificent assistance being given them by Miss Marcia Smith, Librarian of the Adirondack Museum, Blue Mountain Lake. Without Miss Smith's fine cooperation in making valuable documentary research possible, this series would, indeed, not be possible.
The Seventh (1850) Census of the United States, Census of Manufacturers, stated that Adirondack Iron Co., Town of Newcomb, produced 600 tons cast iron valued at $15,000, 600 tons of Rought (wrought) valued at $36,000, used 12,000 tons of ore and 70,000 tons of charcoal, had a capital investment of $15,000 and employed 150 people.
Cast Iron
Cast iron was produced in a cupola furnace, a small blast furnace around 15 - 20 ft. high, 4 - 6 ft. in diameter, and lined with fire brick. Air was supplied from blowers or bellows via tuyeres situated near the bottom of the furnace. The charge was charcoal, pig iron and limestone. As the metal in the cupola was in contact with charcoal, the main tendency was to pick up carbon; alloys could be added here to obtain any desired mechanical properties of strength and hardness. McIntyre directed in 1846 that this recipe of alloying materials be tried, "to every charge of ore put in the blast furnace likely to produce 480 lb. metal, add the following mixture, either with the ore or fuel viz. Manganese 42 lb., charcoal 14 lb., plumbago 8 lbs., saltpetre 2 lbs. making together 66 lbs. The same may be
10 CLOUDSPLITTER
applied with equal advantage in the puddling furnace, say two or three pounds when the metal is fused, and con tinuing to do so at intervals of a few minutes, incorporating it by stirring it with this metal until 66 lbs. are used or until the metal begins to thicken or till, as the workmen say, it comes to nature.
I have consulted an able chemist on the above. He sees clearly that manganese and saltpetre may be very ser viceable but cannot conceive how charcoal and plumbago can be . . . I know not whether it will do any good but anything that has the least probability of aiding ought to be tried and therefore let this be done." Sir Robert Hadfield's introduction of high manganese steel was a landmark in the history of steelmaking, but this was not until 1888!
In contrast to this amateur attempt, the last blast fur nace to be built incorporated one of the most up-to-date innovations of the period. In 1829 a Scots engineer, J. B. Neilson, took out a patent entitled, "Hot Blast for Fur naces"; he found that by heating the cold blast, three times as much iron could be produced from the same amount of fuel and the same amount of blast did twice as much work as the cold blast was able to do; furthermore, the temper
THE IRON DAM.
by Thomas Joyce and John Oxenford
This is the third in a series of articles about our historic blast furnace. The authors continue to explore the great problems the original owners faced. At this point in the series, the authors and editor gratefully acknowledge the magnificent assistance being given them by Miss Marcia Smith, Librarian of the Adirondack Museum, Blue Mountain Lake. Without Miss Smith's fine cooperation in making valuable documentary research possible, this series would, indeed, not be possible.
The Seventh (1850) Census of the United States, Census of Manufacturers, stated that Adirondack Iron Co., Town of Newcomb, produced 600 tons cast iron valued at $15,000, 600 tons of Rought (wrought) valued at $36,000, used 12,000 tons of ore and 70,000 tons of charcoal, had a capital investment of $15,000 and employed 150 people.
Cast Iron
Cast iron was produced in a cupola furnace, a small blast furnace around 15 - 20 ft. high, 4 - 6 ft. in diameter, and lined with fire brick. Air was supplied from blowers or bellows via tuyeres situated near the bottom of the furnace. The charge was charcoal, pig iron and limestone. As the metal in the cupola was in contact with charcoal, the main tendency was to pick up carbon; alloys could be added here to obtain any desired mechanical properties of strength and hardness. McIntyre directed in 1846 that this recipe of alloying materials be tried, "to every charge of ore put in the blast furnace likely to produce 480 lb. metal, add the following mixture, either with the ore or fuel viz. Manganese 42 lb., charcoal 14 lb., plumbago 8 lbs., saltpetre 2 lbs. making together 66 lbs. The same may be
10 CLOUDSPLITTER
applied with equal advantage in the puddling furnace, say two or three pounds when the metal is fused, and con tinuing to do so at intervals of a few minutes, incorporating it by stirring it with this metal until 66 lbs. are used or until the metal begins to thicken or till, as the workmen say, it comes to nature.
I have consulted an able chemist on the above. He sees clearly that manganese and saltpetre may be very ser viceable but cannot conceive how charcoal and plumbago can be . . . I know not whether it will do any good but anything that has the least probability of aiding ought to be tried and therefore let this be done." Sir Robert Hadfield's introduction of high manganese steel was a landmark in the history of steelmaking, but this was not until 1888!
In contrast to this amateur attempt, the last blast fur nace to be built incorporated one of the most up-to-date innovations of the period. In 1829 a Scots engineer, J. B. Neilson, took out a patent entitled, "Hot Blast for Fur naces"; he found that by heating the cold blast, three times as much iron could be produced from the same amount of fuel and the same amount of blast did twice as much work as the cold blast was able to do; furthermore, the temper
THE IRON DAM.
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