138 



GEOLOGY OF OHIO. 



The best sections of the Conglomerate found in the county are in Nel- 

 son, where its entire thickness is shown — one hundred and seventy-five 

 feet — and it forms bold escarpments, which constitute the western bound- 

 ary of the valley of Grand River. These escarpments are known as the 

 Nelson Ledges. They afford the most picturesque scenery to be found in 

 the county, and are noted places of resort for the inhabitants of the sur- 

 rounding region. In the extreme north-eastern corner of the county an 

 island of the Conglomerate has been cut off by erosion from the main 

 plateau. Though less bold in its outline, it has the same topographical 

 character and relation as Little Mountain, in Lake county. 



At the base of the Nelson Ledges the Cuyahoga shale is imperfectly 

 exposed. This is the upper member of the Waverly formation, and will 

 be found fully described in the reports on Cuyahoga, Summit, and Trum- 

 bull counties. A few years since quite an excitement was raised' by the 

 reported discovery of gold at the Nelson Ledges. As is usual in such 

 cases, stock companies were formed, and many dreams of wealth were in- 

 dulged in by those who obtained shares of the stock. It is hardly neces- 

 sary tcJ say that these dreams have passed like "the baseless fabric of a 

 vision." The excitement was caused by the discovery of iron pyrites in 

 certain beds of the Conglomerate — another of the innumerable examples 

 of the mistake of "fool's gold" for true gold. A little knowledge of 

 geology would have prevented this error, and would have taught the 

 sufferers that gold could never be found in paying quantities in Portage 

 county. That minute particles may sometimes be detected in the super- 

 ficial gravels is very probable, since these gravels are largely made up of 

 quartz pebbles, which are only rolled masses of the quartz veins con- 

 tained in the crystalline rocks of the Canadian highlands, and which 

 frequently carry a little gold. It is also probable that with sufficient 

 care in searching for it, an infinitesimal quantity of gold might be de- 

 tected in the Conglomerate, as the quartz pebbles it contains were doubt- 

 less derived from the same source with those to which I have already re- 

 ferred; but it may be confidently predicted that the precious metal will 

 never be obtained from either of the sources mentioned in sufficient 

 quantity to compensate the most idle and worthless member of the com- 

 munity for any time he may spend in its search. 



COAL MEASURES. 



Coal No. 1. — Nearly three-fourths of the surface of Portage county is 

 underlain by coal-measure rocks, and they once covered its entire area. 

 Prom the valleys of the Mahoning and Cuyahoga they have been re- 

 moved by erosion, so that in the northern part of the county they are re- 



