THE LOWER COAL MEASURES. 213 
collected here by Newberry, almost all of which are not only new to 
science, but almost all of which are confined to the acre or two of can- 
nel that lies in the center of this mine. They have never been found 
elsewhere. Newberry justly says of this locality, “ there are few places 
in the world more interesting to the paleontologist than the Diamond 
mine at Linton, since we get here such a view of the life jof the 
carboniferous age as is afforded almost nowhere else.” The field will 
soon be exhausted. 
So far as the workings and explorations have now proceeded, it 
appears that the basin of the Diamond coal has its longer axis in the 
direction of 8. 65 W., this axis having a length not to exceed 800 yards, 
while the greatest breadth would not be more than half this distance, 
and approximately at right angles to the main axis. . 
The coal is anomalous in this further respect, that it does not rest 
on a fire-clay. The cannel above named has underneath it a hard and 
irony band in many instances, and in no case in the center of the basin 
is there the slightest hint of fire-clay. So firm a bottom allows the 
pillars to be reduced to small dimensions. Nine feet square is counted 
ample to support a heavy hill permanently, the rooms being worked 
21 feet wide. 
The mine has been open for a long time, having been worked for 
neighborhood use before railroad transportation was available. There 
are no surveys that show how much has been worked out, but the 
estimate of the present owners places the exhausted area at 45 acres. 
At the present output of 275 to 300 tons per day, there is not a 
long term to the thick coal. The seam has not yet been followed below 
3 feet, but at the present writing, the northeast entry, which is furthest 
under, has gained a foot of coal after passing the lowest point on the 
top of the “hill.” Whether a second basin exists in this direction will 
soon be learned. ‘The indications from outcrops are not favorable to 
such a view. 
The physical and chemical properties of the coal agree with those 
of the Upper Freeport seam, as generally found in this region. The 
descriptions of the Big Vein at Salineville would require no modifica- 
tion here. 
An analysis of the average output gives the following results: 
