148 ONTARIO DIVISION. 



witliin two miles of the lake shore, and where it can not be less than fifteen or twenty 

 miles wide. This, too, is the most important part of the series, as the iron ore beds are 

 better developed tlian either east or west. At Rochester, the series is about eight miles 

 wide, which width it retains to the Niagara river. It crosses the Genesee below Rochester, 

 and forms the little ridge on the north side of the canal, or a low terrace which runs nearly 

 parallel with it. The canal soon intersects this ridge, whence it then extends on its south 

 side to within eight or nine miles cast of Lockport. From Lockport it forms a sort of slope 

 or terrace, which extends to Niagara river. 



Oneida lake, and the low marshy grounds in Cicero, are excavated in this group. Its 

 distribution, and the width of the formation, together with the course of the southern 

 boundary, may be seen by an examination of the map : the belt is colored green. 



Relations of the Clinton group. To the eastward this group is superimposed upon the 

 Oneida conglomerate. The disappearance of this mass, as the series extends westward, 

 seems to alter or change its relations ; for instead of passing beneath the Medina sand- 

 stone, which it meets in the northern part of Oneida county, it takes a position superior to 

 it, and hence the Medina sandstone becomes the supporting mass or base throughout its 

 whole distance to the Niagara river. Superiorly the group is merged in a shaly sandstone, 

 which, if it does not coalesce with the more perfect limestone called the Niagara, still does 

 not disappear abruptly and form a strong and well marked line of demarkation with it. 



The relations of this group, then, are by no means ol)scure on the route I have described. 

 We should expect, however, from so perfect a development of a series within this section 

 of the State, that it woidd also appear within its bounds wherever the inferior and superior 

 rocks are found ; but this is not the case. Thus in the valley of the Rondout, the Oneida 

 conglomerate forms an important rock, and ought to be succeeded by the Clinton group ; 

 but instead of this being the case, it is wanting. The relations of the rocks of this part of 

 the State are represented on PI. XX. Section 3 : see also the same plate, section 2, which 

 extends across the valley of tlie Schoharie creek. The same absence of this group will be 

 noticed in the section at Cherryvalley, still farther west, on the main sectional route from 

 Albany to Auburn. It is only, therefore, in the direction and vicinity of the Erie canal, 

 that we are to look for this series ; parallel with whicli, it extends across the State, from 

 near the eastern bounds of Springfield or Warren in Herkimer county, to the Niagara river. 



Contour of the country over which the Clinton group extends. The most level and unin- 

 teresting part of the Stale, is that which is underlaid by the Clinton group. To be satisfied 

 of the truth of this statement, it is only necessary to pass over the level and swampy lands 

 about Oneida lake, and the Cicero swamps. The long levels of the canals, too, extend 

 over this series. There is, however, some interest in the scenery of the deep gorges : 

 thus, at Cruger's in Herkimer county, but especially in the deeper and wider gorges of the 

 Genesee and Niagara rivers, the scenery is imposing ; but in consequence of the absence of 

 disturbances in this rock, the surface above it is invariably dull and monotonous. If, how- 

 ever, this section of the State rises at all into ridges, they arc not all connected with this 



