18 GEOI-OGY OF THE THIRD DISTRICT. 



northeastern part of Oneida, and the whole of Lewis county east of Black river. They form 

 a continuous mass, being the south and west part of that comparatively immense and beauti- 

 fully circumscribed nucleus, which from a height, according to Professor Emmons, of 

 nearly six thousand feet, descends with great irregularity, and disappears under the transition 

 rocks which encircle it, and which border the St. Lawrence, the Champlain, the Mohawk and 

 the Black river. To the southwest, the primary rocks do not again appear, until they rise to 

 form the Ozark mountains of Arkansas, and the Iron mountain of Missouri. 



The primary rocks of the district belong to the third range of the United States. The 

 ranges differ in many of their characters, and in their geographical position. The first is the 

 granite, having the characters usually given of this rock. It contains few extraneous mine- 

 rals, is deficient in limestone, in iron ore, and disposed to decomposition. It is an extensive 

 rock from Virginia south, and is the first rock which is met with going west from the coast. 

 The second range is the gneiss. This is the same in all respects with that of the east part of 

 the State, and extends through the Union, being placed between the other two ranges. Its 

 characters and associates are pretty uniform throughout its long course. The third differs 

 greatly from the other two : Mica is rare ; amphibole more abundant ; less disposed to decom- 

 position than the two other ranges ; rich in magnetic iron ore, which is only incidentally 

 found in the others, showing no mine of it in cither of those ranges. The third range is 

 extremely rich in extraneous minerals, and hes to the west of the '-other two. 



A referencfc to the map will show the boundaries in the third district, of the Primary and 

 Transition classes. Through Lewis county, Oneida and Herkimer, they are well defined, 

 being natural ones formed by Black river, tlie valley of Black creek and Spruce creek. In 

 Montgomery the boimdary is wholly artificial, and a reference to the map is necessary to 

 understand it. The great mass lies to the north of the road which leads from Garoga Post- 

 office, by Lasselsville to Brocket's bridge,, on East Canada creek. East of the Post-office, 

 after crossing Klip Hill, it pursues a northeast course, keeping within a" mile or two to the 

 northwest of the villages of Kingsborough, Mayfield Corners and Cranberry post office, to 

 Sacondaga river ; down which river it passes on the northeast side, forming the high hill or 

 low mountain vfhich runs parallel with the river, and for a mile and more from its bank. It 

 joins the high range of primary hills in Saratoga county, of which it forms a part. In the 

 four counties, its outline is that of a segment of a rude circle. 



The characteristic features of the Primary region .are its high insulated ridges, with parts 

 more or less level between them ;^ the extent of level surface somewhat considerable, in 

 which are numerous lakes, ponds and meadows. The most hilly portions seen, were near to 

 the east side of Montgomery, the greater part of the northern portion of Herkimer, the north- 

 west part of Oneida, and the east part of Lewis ; the hills diminishing north, corresponding 

 with the slope at the northwest of St. Lawrence county. Some of the hills, such as Oak 

 mountain. Royal hill, Kingsbury mountain, &c. appear to owe their elevation above the 

 surrounding surface, to the same cause which raised the Noses, Little falls, &c., their forms 

 elongated and mural being too regular and abrupt to be the relics of denudation. These 

 high abrupt primary ranges are more numerous in Saratoga county, and show the Cham- 



