56 TRANSACTIONS OF THE [Nov. 18, 
the trend is changed abruptly and the limestone ridge, which 
from Wilburton has been holding a widely southwest direction, 
is bent sharply southward and the dip changes so as to be al- 
most eastward and very steep, 40 to 70 degrees, sometimes little 
less than vertical. ‘he strike is not true but, as pointed out by 
Prof. Hill, the limestone appears to be bent westward at several 
places. This is evidence of overlapping anticlines here as on 
the Choctaw railroad. The ridge is distinct as far as String- 
town, 38 miles from McAlester, but thence decreasing, it dis- 
appears before Atoka has been reached, for it is wanting where 
its place is crossed by the branch road from Atoka to Lehigh 
and Coalgate, the only limestone seen along that branch being 
the thin bed already mentioned as seen just north from Atoka, 
on the main line. Prof. Hill found it further southward, but the 
writer failed to discover it at two miles south from the Lehigh 
branch. The axis must pass very near where the thin limestone 
was seen, for coal occurs at about two miles west from Atoka, 
where the rocks are dipping westward. The mines at Lehigh 
and Coalgate are on the opposite side of the basin. 
The abrupt elevation of the Limestone anticline northward 
affects the distribution of the coal and clearly causes a very 
rapid narrowing of the basin, for Mr. McConnelly, the Atoka 
Coal Company’s prospector, says that the coal is cut off by the 
Limestone Hills at several miles north from Coalgate. 
It was the writer’s intention to go across the country from 
Lehigh to Dougherty, a station 80 miles away, on the Gulf, 
Colorado and Santa Fé railroad, but the long-continued heavy 
rains, unusual in summer, rendered it probable that the rivers 
could not be forded and the project was abandoned. Limestone 
in great quantity and with almost vertical dip is reported as 
occurring at several localities in this interval. Manganese oxide 
and magnetite have been obtained in limestone, more or less 
oblitic, at not more than 20 miles from Lehigh, near the line of 
the proposed Denison and Northern railroad. Limestone is said 
to occur at Stonewall, also on the Canadian river near the Choctaw 
railroad crossing, and on the Dougherty road about 25 miles 
from the latter place. The last may be the work referred to by 
Prof. Hill as of Silurian age.* 
The conditions along the Gulf, Colorado and Santa Fé rail- 
road are wholly unlike those observed in the eastern part of the 
Territory. At Purcell, on the Canadian river, on the border of 
Oklahoma, one is in the *‘ Red beds,” beds of soft sandstone and 
*The region north and south from Lehigh was studied with great care by Prof. 
Orestes St. John several years ago, but the writer was not aware of this fact until he 
reached Lehigh, so that he was unable to take advantage of the investigations. 
