ANNUAL REPORT—MINING. 
43 
condition on exposure and handling; which circumstance 
adds greatly to the facility with which it is taken from the 
mines. * 
Its mineralogical and chemical constitution is as follows, ac¬ 
cording to an analysis by Prof. Cassels : 
Peroxide of iron, being— 
Iron... . 53.72 
Oxygen.. 23.00 
- 76.76 
Silica. 10 
Clay. 4 
Sesquioxide of manganese. 1.05 
Water. 6.00 
Loss. 2.21 
100.00 
From this, it appears, not only that the ore is rich in iron, but 
that it is to a remarkable degree wanting in that large proportion 
of silex which characterizes many other ores; and which makes 
the smelting of them so much more laborious and expensive. 
The ore in question requires on this account no other flux 
than the clay with which it is found mixed in the bed. 
Owing to the peculiarities of composition, and the hardness 
of the iron it produced, the Dodge ore has been, until very 
lately, considered unavailable for some uses, and therefore 
limited in demand. Experiments with it, in connection with 
Lake Superior iron, have shown, however, that it is possessed 
of great value, both for the manufacture of steel—of which it 
produces an excellent quality in the proportion of one to two 
—and for the working into rails. 
In the manufacture of iron rail for railways, experiment has 
shown that, by using the Superior iron for the body of the 
rail and the Dodge iron for the top, there is secured by this 
means, not only the requisite strength and toughness, but a 
surface that does not laminate and sliver up, as much of the 
railway iron does, but, on the contrary wears smooth and hard, 
like steel. This quality cannot fail to create a very great de¬ 
mand for this iron, when the manufacture of railway iron be¬ 
comes a common thing iu the west. Not only so, it will also 
create for it a demand, because of its availability for a multi- 
