WITH THOSE OF NEW YORK. 269 



The Lake Erie shore, from the New York and Pennsylvania 

 line (a point to which previous investigations had extended) 

 to Cleveland, presents nothing of peculiar interest, being occupied 

 by the rocks of the Portage group, which for the most part are 

 destitute of fossils, except the remains of marine vegetables and a 

 few Goniatites. The accompanying section ( PI. XII ) extends 

 from Cleveland to the JVIississippi river, there being no rock rep- 

 resented which was not actually seen. Though westward, from 

 Leavenworth, Indiana, it passes a little north of the line examined, 

 in order to present the great limestone formation on the Missis- 

 sippi, as a more prominent feature, than further south, it being 

 low and obscure near the mouth of the Ohio.* 



The rocks seen near Cleveland, Ohio, are perfectly identical 

 with those of the middle portion of the Portage group, or Gardeau 

 flag-stones, being a continuation of the same as traced from New 

 York along the lake shore. In following the road to Cuyahoga 

 Falls, the Portage sandstone, or upper part of the group, is seen 

 at Newburgh, and is there underlaid by green shale. These are 

 equivalent to the Waverley sandstone of the Ohio Reports, as 

 was afterwards ascertained by visiting the quarries at Waverley. 

 From Newburgh we pass over the shales and sandstones of the 

 Chemung group, till we an'ive upon the conglomerate which is 

 well developed at Stow and Cuyahoga FaUs. 



This conglomerate which, so far as I could discover, is identi- 

 cal with the outliers of a similar mass in the southern part of New 

 York, is the fundamental rock of the great coal formation through- 

 out the greater part of the western country, appearing everywhere 

 either as a coarse sandstone or a pebbly mass, and affording an 

 unerring guide to the proximity of coal. Some portions of the 

 mass at Cuyahoga Falls are destitute of pebbles, and furnish a 

 fine reddish or brownish sandstone used for building. The greater 

 part however is composed of coarse materials, with white quartz 

 pebbles. This character is exhibited in great perfection along 



* I am under obligations to Dr. Owen for much valuable information of the north- 

 western region beyond the limits of my researches, and I had hoped to be able to present 

 a section which he liberally furnished me, extending across the formations from Prairie 

 du Chien to Tennessee, and crossing the Rock River near Dixon's Ferry, and the Ohio 

 near Roclqjort. This section exhibits the northwestern margin of the great Illinois coal 

 formation as resting upon the Clifflimestone. 



