FULTON COUNTY. 103 



with the coal seams above, or the limestones below, because of its close resem- 

 blance to some other sandstones of the Coal Measures. 



St. Louis Limestone. The outcrop of this formation appears to be restricted 

 to the valley of Spoon river, between Bernadotte and Seaville, and there are 

 but few points where it is well exposed. At Bernadotte, there is only from 

 six to ten feet of this limestone exposed above the lower water level of the 

 river. The rock is concretionary in structure, and contains Lithostrotion pro- 

 liferum and L. canadense, the most characteristic fossils of the upper division 

 of this formation. Just above the mouth of Barker's run, on Spoon river, the 

 following section of this limestone group was seen : 



FEET. 



Gray concretionary limestone 10 



Bro. magnesian limestone 12 



Arenaceous beds, partly hidden 16 



The two lower divisions of the above section are tolerably even bedded, the 

 layers varying in thickness from six inches to two feet, and will afford an ex- 

 cellent building stone. The magnesian limestone is especially valuable for 

 culverts and bridge abutments, where a rock is required to resist the combined 

 influenceof frost and moisture. A very fine specimen of Lithostrotion canadense 

 was fonnd at this locality by Mr. James H. Cooper, and presented by him to 

 the State Cabinet. We saw no other locality in the county where so great a 

 thickness of this formation was exposed as at this point. 



Economical Geology. 



Bituminous Coal. The great mineral wealth of this county, as must be ap- 

 parent from the perusal of the preceding pages, consists in its almost inexhausti- 

 ble beds of coal, which are so distributed as to be easily accessible to every 

 portion of the county. The three lower seams, ranging from two to four feet 

 in thickness, outcrop on all the principal streams in the southern and western 

 portions of the county, while coals 4, 5 and 6, the thickest aud most valuable 

 seams known in the northern portion of the State, underlie the central and 

 northeastern portions of the county, and are easily accessible at any point 

 where a large supply of coal may be required. These coals underlie nearly, or 

 quite, seven townships in this county, with an aggregate thickness of about 

 fourteen feet, and throwing out of the calculation entirely, No. 5, which is more 

 local in its development than the other two, we still have an aggregate of from 

 nine to ten feet of coal, equal to 9,000,000 tons of coal to the square mile, as 

 the product of these two seams, from the central and northeastern portions of 

 the county alone, and within one hundred and fifty feet of the surface, at the 

 general level of the prairie region. Coal mining is yet in its infancy in this 

 most highly favored region, and until the construction of the two railroads 



