536 GEOLOGY OF OHIO. 
tuyeres; the blast pressure used is at present 3 to 3g lbs., and a tem- 
perature of about 900 degrees. The furnace at Girard had not been 
running for some time, but at present is blown in again. The Hubbard 
furnaces of Andrews & Hitchcock, at Hubbard, Trumbull county, are 
making foundry and mill iron from a mixture of Lake Superior, Canada 
and native ores. They are equipped with three blowing engines of 66 
by 30 in., 84 by 35 in., 84 by 36 in., respectively, and make about 60 
_ tons a day from each stack. The product for the year ending June 30, 
1882, is 27,000 tons. The furnaces of the Brier Hill Coal and Iron Co., 
three miles northwest of Youngstown, comprise four stacks; they are 
provided with vertical blowing engines, using a blast pressure of 8 to 
9 lbs. ; the blast engines are 84.in. by 8% feet, with 36-in. steam-cylinder, 
running from 30 to 40 revolutions per minute. ‘The furnace uses as a 
flux Lowellsville limestone, and is lined with Savage Mountain and - 
Star fire-brick; the furnace is equipped with Thomas pipe-stove (a 
simple double-legged pipe), 36 pipes to a stove; the ore is almost en- 
tirely Lake Superior. | 
During 1882, about 5,000 tons of native blackband from Mineral 
Ridge were used. This company has a small Spiegel furnace, using 
Spanish ore; this Spiegel furnace has nearly straight lines, works with 
a closed front, and is blown by four tuyeres, is 45 feet high by 10% in 
the bosh. 
The Eagle furnace, at Brier Hill, is an old furnace out of blast at 
the date of the Survey; it is built against a bank, but is provided with 
a short water-hoist, similar to the one described as in use at the Grant 
furnace at Ironton ; the furnace has seven tuyeres, and is equipped with: 
three pipe stoves. The Brier Hill furnaces discharge the slag from a 
small slag-tuyere at one side of the furnace front. The large Brier 
Hill furnace has nine tuyeres and a steam-hoist. The Niles furnace, at 
Niles, is at present run by the Arnold Furnace Cumpany, and make a 
speciality of a soft foundry pig, under the brand of the “Arnold Iron.” 
The furnace is a small one, provided with a wooden column water-hoist 
and pipe stoves. 
In regard to the working of the furnaces in the Mahoning Valley, 
figures were taken from the charging books of several companies, and 
will be found in the table on page 541. 
In regard to the character of the iron produced from these furnaces 
little need be said; from the character of the ore the iron is mad 
