654 GEOLOGY OF OHIO. 



Above the Zoar limestone, as given in the section, in places, two seams 

 of coal are found, before reaching the coal next below the Great Vein. 

 Two seams are also frequently found below the blue limestone, which 

 again, at times, forms the roof of another important coal seam. I have 

 not observed the outcrop of any of these coals in this neighborhood, but 

 the outcrops of four such coals are to be seen in the hills in the neigh- 

 borhood of Maxville, and I have indicated their position in the section 



Of the iron ores the upper one, which is found at an altitude varying 

 from ninety to one hundred and fifteen feet above the Great Vein, and 

 one called the gray ore, found id a distance of thirty-five to forty-five feet 

 below the Great Vein, are the most important and the most valuable. 



The first exhibits its best characteristics at Iron Point, north of Shaw- 

 nee, where it reaches a maximum thickness of three feet, and appears to 

 form a continuous stratum exf ending through the hill. It seems to have 

 been originally a blue carbonate, now mainly changed in the outcrops to 

 a sesquioxide. It roasts very readily and yields a large percentage of 

 iron, which is a little cold short unless a mixture of other ores is used. 

 Indications of its presence are to be seen near the top of almost every 

 hill which reaches its horizon, and its outcrops have been observed in 

 many places. It is the ore used in both of the furnaces at Shawnee, 

 mixed with about one-sixth Lake Superior ore. The gray ore appears to 

 be quite persibtent, ranging in thickness generally from one to three 

 feet, sometimes thinning down to a few inches, and in places disappear- 

 ing altogether. It is the ore used in Mr. Baird's Pioneer Furnace, west 

 of Shawnee, and produces a gi od mill and foundry iron, without any ad- 

 mixture of foreign ores. 



It is largely developed and of excellent quality in the hills about Old 

 and New Straitsville, and in nearly all the hills which reach its proper 

 horizon, to the west line of Monday Creek township. Separated in a 

 few places by shale intervening between it and coal No. 5, its ordinary 

 position is directly beneath the fire-clay of this coal, and it is often as- 

 sociated with a cherty drab limestone. When the ore is well developed 

 it seems to take the place of the coal, the latter showing only a faint 

 trace of carbonaceous matter. Where drifts have been carrir-d into the 

 hill, the ore has been found, on an average, nine feet below the coal, the 

 interval being filled with fire-clay, and the ore resting on flint, limestone 

 and sometimes in sand-rock. 



It is generally oxydized and contains a large percentage of sesquiox- 

 ide. Although here called the gray ore from its color when not oxydized, 



may well bear the name of the " Baird ore " from the name of the pro- 



