370 GEOLOGY OF THE SECOND DISTRICT. 



The small uplifts in this county, in addition to the cfl'ects already spoken of, have produced 

 a slight anticlinal axis, which traverses the county from a point half way between French 

 creek and Cape Vincent, nearly cast and west across the county. It does not, liowever, dis- 

 turb the face of the country, and would be unsuspected without an examination of the present 

 water courses. The efl'cct has not been sufticient to overbalance the combined clTect of the 

 northeast fractures, and the currents which have swept through them. Some of the most 

 distinctly marked valleys are the following : 1st, from Chamont, passing through Depauville 

 to Lafargeville, a distance of twenty miles ; 2d, from Watertown towards Evans' mills, on 

 a line with the deep channcllings already described. Three or four others, of less length and 

 importance, on the north side of Black river, I pass by unnoticed. 



Southwest of the river, extending up from Henderson towards Watertown, is another 

 produced by the operation of the same class of causes already adverted to. 



In pursuing our examination in the Southern townships, we observe the same arrangement 

 or direction of the rivers ; but some doubts necessarily arise, when we examine critically 

 the rocks and all the conditions of the surface. Probably, however, some of these causes 

 have influenced the direction of the southern creeks, in order to give them a course parallel 

 to those already noticed ; but these creeks have, for a large portion of their distance, cut 

 at least apparently their own channels. Rising in the highest ground, both geograpliically 

 and geologically, in the fragile slates and shales of Loraine, Rodman, and the adjacent part 

 of the county of Lewis, they have formed deep narrow gorges, in which they flow for the 

 first twenty miles of their route to Lake Ontario. At their egress from these gorges, they 

 have also worn into the trenton limestone a few feet ; but when we compare the phenomena 

 presented by these gorges, with the wider and shallower valleys north of Black river, we see 

 that the latter arc recent, and that they must have been formed principally by the present 

 creeks which flow through them. 



Instead of confining our views to Jefferson county, we may extend them to the correspond- 

 ing part of St. Lawrence, or rather from the foot of Lake Ontario to the head of Lake St. 

 Francis, a distance of one hundred miles. In this distance, taking in a breadth of fifteen 

 miles upon the cast side of the St. Lawrence, we discover the whole of this area of fifteen 

 hundred square miles, channelled and grooved in the same manner as the parts of Jeflferson 

 which have been under consideration. We may look first at the direction of the rivers : they 

 all fall into channels determined by previous fractures. The fact that in Jeflerson they run 

 southwest, is a matter of no consequence ; the anticlinal ridge is so slight that the fractures 

 cross it, or are continued through it from both sides. We may look at the lakes ; we see that 

 their longer axes lie parallel to the valleys already described. We may regard them all in 

 the same light that we do Lake St. Francis — merely an expansion of the St. Lawrence ; so 

 the smaller lakes are only deeper and wider channels of the creeks and rivers which flow 

 through ; such channels, from causes not well determined, having been more deeply as well 

 as more widely excavated. 



