THE IRON ORES. 415 
and sometimes they recede 12 or 15 feet fromit. They are not gathered 
into a seam, but are scattered irregularly through the clay and shale. 
They consist of a very fine-grained and consequently heavy blue car- 
bonate. They are generally more or less symmetrical in shape, inclining 
to a discoidal form. A marked peculiarity of the ore is that it contains 
throughout its substance fragments of fern leaves, and other carbo- 
niferous plants in exquisite preservation. When freshly broken, the most 
delicate venation of the leaves can be observed. Insect remains have 
not been reported in these kidneys, but their occurrence would be no 
surprise to those that have studied the deposit, as there are many points 
of resemblance between these nodules and other Carboniferous conere- 
tions which have yielded such remains. The ore maintains this peculiar 
fossiliferous character, in places, as far south as Willard, Kentucky. 
The ore is rich in iron, and the quality is not in any respect un- 
favorable, so far as analysis has shown, but the fact that it hes scattered 
to such a degree, forbids the mining of it. Tradition records, however, 
that it was the first ore ever turned to account for iron making from 
the Hocking Valley. A boat load was taken to the Mary Ann furnace, 
near Granville, in the early days of the Ohio canal. On both sides of 
the Ohio Valley,.as will be presently shown, this ore has been and still 
is quite extensively worked. 
From this review it will be seen that all of the ore now mined in 
the Hocking Valley comes from the three well-marked horizons named © 
below: 
Blackband or Iron Point ore, accompanying Upper Freeport coal. 
Limestone or Baird ore, borne by Ferriferous limestone. 
Block ore, below Lower Mercer limestone. 
Several other horizons have been named at which ores of various 
grades and character appear. Some of these ores have been experi- 
mentally worked, but none of them have been found to justify larger 
and continuous operations. 
Of these three ores the most accessible portions have already been 
largely taken. The outcrop furnishes not only the cheapest, but on 
every account the best ore of the seam. This outcrop ore has been 
followed or “tailed” into the hills, at least as far as the empirical 
mining rule, “a foot of stripping for an inch of ore,’’ would require. 
This is certainly true for most of the lands naturally tributary to the 
