410 The American Geologist. Jnne, ia&4 
more argillaceous, quite soft, and is known as "clod." At 
Stahl, Adair county, Missouri, it is said to become two or 
three feet in thickness. The total thickness of the coal varies 
within limits of only a few inches. The clay parting (No. 4) 
is especially notable in its persistency and uniformity. A 
second parting, from a half to three-quarters of an inch in 
thickness, is in many places present about three inches from 
the bottom of the lower bench. In mining, the lower lime- 
stone is not always encountered, as the fire-clay frequently 
thickens considerably. 
Not less striking than the extent of the Mystic coal seam 
is the simplicity of the structure of the region. In addition 
to the two limestones mentioned above, there are two others, 
known locally as the "seventeen" and "fifty" foot limestones 
from their general occurrence at those hights above the coal. 
These levels are not absolutely correct, but the variation from 
them is usually slight. The intervening spaces are filled with 
various argillaceous shales. 
A section along the C.R., I. & P. railroad from the east side 
of the Chariton river in Appanoose county to Harvard in 
Wayne county, is represented in figure 2. This shows the 
Fig. 2. Section from Sharo7i to Harvard. 
general simplicity of structure and the prevailing dip to the 
southwest. 
The coal is approximately level, yet it exhibits considerable 
variation in elevation. At Dean, in the southeastern corner of 
Appanoose county, it is 825 feet above the sea level; at Cin- 
cinnati, in the southern part, 995 feet ; at Centerville, in the cen- 
tral part, 880 feet; at Mystic, 908 feet ; at Numa, seven miles 
southwest, 900 feet; and from there it dips southwest nearly 
ten feet per mile to Seymour, where it is 839 feet above sea 
level. Thence it rises slightly to the west. It is thus seen 
that Numa and Cincinnati are situated on the crest of a slight 
anticline, which apparently has a northwest to southeast di- 
rection. Other small anticlines are doubtless present in this 
field, but sufficient detailed work has not yet been done to 
locate them. 
