1871.] 151 [Lesley. 
mined for the furnaces on the Lehigh river. It is a mixture of magnetic 
crystals, and specular plates of sesquioxide of iron, with quartz, feldspar 
and mica, in a thousand varying proportions. Sometimes the bed will be 
Fre. 15. 
composed of heavy, tight, massive magnetite (or titaniferous magnetite), 
with very little quartz, &c. At other times the bed will be composed of 
a loose, half-decomposed mica slate, or gneiss rock, full of scattered crys- 
tals of magnetic iron. 
The ore is, in fact, a decomposible gneiss rock, with a varying per cent- 
age of titaniferous magnetic and specular iron ore, sometimes forming 
half the mass, and sometimes constituting almost the whole of it. 
The compact varieties will yield between 50 and 60 per cent. of pure 
iron, as in the case of the ore now being mined in the Sergeant Shaft, 
near the Forges. Mr, Frazer’s analysis of this ore is as follows : 
Magnetic OIGG,,....-.-.- SM OCUO sie vrs ok ATOM, ose. Ob. 0. Cell 
WIGAN Ol es os Save? (Ui lope is «yeaee, | PIVOMIUIN...660500 D.C. | 
Residuum of quartz, &c..............12.86—with a trace of sulphur. 
The specimen was obtained from the tunnel, a hundred feet beneath 
the surface, and shows an intimate mixture of crystalline titanic ore, 
magnesian mica, a little hornblende, a little labradorite, and a little spec- 
ular iron. 
This kind is difficult to smelt in the high-stack blast-furnace ; but 
makes the best iron in the world when smelted in the Catalan forge ; and 
is of great value for the lining of puddling furnaces. It serves the same 
purpose as the Lake Superior ore, which is brought in large quantities to 
Pittsburgh, and the surrounding district of Eastern Ohio and Western 
Pennsylvania, for lining puddling furnaces, and to mix with poorer ores | 
in the blast-furnaces. Formerly, in the E. Ohio Mahoning district, the 
mixture was: one-fourth Lake Superior, one-half coal measure ore, and 
one-fourth mill cinders. Since the organization of the Lake Superior 
Iron Ore Trade, sufficient quantities come forward to enable the iron 
masters to mix one-half Lake Superior. The Sharon Furnace on the Beaver 
river runs wholly upon Block Coal and Lake Superior Ore. The titan- 
iferous magnetic ores of the Ottawa region, in Canada, are also brought 
by.a long and expensive route to Pittsburgh, to mix with Pennsylvania 
