928 GEOLOGY OF OHIO. 
in thickness, occurs. It is named in the section the Iron Point ore. 
This identification is not beyond question, but the interval, and the 
character of the ore, and its outciop, seem to make it probable. 
Aninterval of sixty-five feet filled with sandstoneand with reddish shales 
next succeeds, without any recognized elements of economical value, 
above which the Cambridge Limestone finds place, completing the section. 
The limestone is one hundred and seventy feet above Coal No. VI, which 
is a smaller interval by ten or fifteen feet than is generally found. | 
The section is thus seen to be very full and satisfactory. It answers, 
without change, for all of the leading elements of the scale throughout 
the western part of York township and the eastern part of Starr, and 
through Brown and Madison townships, or, in other words, to the line of 
the Marietta and Cincinnati Railroad. It is repeated with almost iden- 
tical measurements in Rich Hollow Hill, three miles south east of Zaleski 
(Section 80, Madison township), where the westernmost ex pele of the 
Cambridge Limestone in that vicinity is found. 
Two sections, taken respectively at Ironton and on the river hills of 
the Monitor Furnace lands, opposite Ashland, Kentucky, will next be 
presented. These sections faithfully represent the lower Coal M: asures 
of this part of the Ohio Valley. An average of many sections would 
scarcely change the measurements found by the engineer’s level in the 
hills which were celected for this purpose. 
The section in the right hand column was taken immediately back of 
Ironton. The biock ore, which is made the base, lies sixty feet or more. 
above low water. It is the highest of the three seams of block ore that 
constitute so important an element in the supply of the wertern furnaces 
of thedistrict. It is well shown at Kronnacher’s spring house, just above 
the Iron Railroad. It is here two feet in thickness, and is rich in iron, but 
it isaleo highly charged with sulphur, and it has, therefore, after repeated 
trials, been. rejected as worthless for the blast furnace. Its character has 
been discussed on preceding pager, and nothing need be added here. 
The heavy ledge of sandstone that covers it has been worked in the 
neighborhood for furnace hearth-stones. On the Kentucky side of the 
river, especially, stone from this horizon has a very good name in con- 
nection with this use. The Belfont hearth-stone quarries belong here. 
A coal seam, locally known as the Conway coal, is found forty feet 
above the Block ore. It has here a thickness of two feet, and has been 
worked, in the small way, for neighborhood supply. It is through this 
coal, and the rocks associated with it, that the tunnel of the Hecla 
- Furnace turnpike has been carried. A prostrate tree is finely shown in 
