Part I. Report of progress in 1869, by J. S. Newberry, chief geologist. Part II. Report of progress in the second district, by E. B. Andrews, assist. geologist. Part III. Report on geology of Montgomery County, by Edward Orton, assist. geologist.

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in the Adirondacks, and in Canada. It is the ore brought to us under
the name of the Champlain ore-from the fact of its occurrence on the
shores of Lake Champlain-and is that mined so extensively in southern
New York, New Jersey, and further south along the same line. From
its abundance in the localities I have cited and its proximity to the anthracite coal of Pennsylvania, this ore has formed the basis of a very
large manufacture in the Eastern States, and has furnished more of the
iron produced in this country than any other single variety.
As found in Canada and along the Alleghanies, the magnetic ores are
extremely prone to contain certain impurities, which injuriously affect the
metal produced from them. These are principally phosphorous in phosphate of lime, and sulphur in the form of sulphide, or iron pyrites. Of
these the phosphorous renders the iron " cold short," or brittle when cold;
and the sulphur "red short," or tender at a red heat. Many of these ores
contain also a large percentage of titanium, by which they are rendered
refractory, and the iron made brittle. These defects in the eastern magnetic ores almost preclude their use for the finer qualities of iron and
steel, and yet they are destined to form an important element in the manufacture of iron in Ohio. Iron making is, in one aspect, much like oil
painting, for, as the painter gets his finest effects by skillfully blending
many tints, so the ironmaker can only obtain his best results by using
in the furnace several varieties of ore. The iron ores of Eastern New
York and Canada may, by the cheapness of return freights, be delivered
within our territory at a price so low that they will continue to be used
as they now are, in considerable quantities, by our iron smelters. Some
of the Canadian ores can be furnished on the Lake shore, at a very low
figure, but these ores are so largely contaminated by sulphur or titanium
that they are, at present, but little used. When, however, we shall have
introduced the Swedish roasting furnace, which will remove, at little
cost, three, and even four, per cent. of sulphur, we may expect these
ores to be much more largely imported than they now are.
The ore next in point of richness to the magnetic, is that called " Specular iron," which consists, when pure, entirely of peroxide. This is a
crystalline ore, generally having a metallic appearance, and takes its
name from the speculum-like reflections from its polished surfaces.
When free from foreign matter, this ore contains 60 per cent. of iron,
and 40 of oxygen. Most of the Lake Superior ores are of this character,
as are also those of the Iron Mountains of Missouri. To us the Lake
Superior ores are of immense importance, as will be seen from the fact
that at least two-thirds of all the ore mined in the Marquette district are
brought to our State, and this ore constitutes the main dependence of all
that great group of furnaces which have been constructed in the northern part of the State within the last twenty years. The product of the
Lake Superior iron mines for 1868 was 507,813 tons, for 1869, 643,283