QUATERNARY DEPOSITS. 
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is, friction in the form of rubbing and collision, occasioned by the movement of the boulder 
itself; and the second, alteration from exposure to the weather, which, commencing with the 
angles and edges, finally leaves the mass in a globuliform state, should its nature admit of 
alteration or decomposition. In North and South Carolina, where granite of a readily alterable 
character exists, rounded masses of the kind are in many parts extremely numerous; they 
have, however, undergone no change of place, but merely a concentric decomposition in place. 
Boulders, with some exceptions, are found over the whole of the district exclusive of its 
southern border, where they were not noticed, but yet may exist. The whole of them, with¬ 
out an exception south of the Helderberg range, have been transported from north to south, 
or rather from a northern position. The greater number consist of primary rock, which have 
been carried a much greater distance than any of the others ; and as a general rule, the farther 
they were seen to the south, the smaller was their size. The distribution of the boulders is 
very unequal, very numerous in some places, and but few in others. With some exceptions, 
they are generally found upon the surface, frequently upon the tops of hills or on their sides ; 
appearing in almost all their localities as if but recently dropped, and that no change had 
taken place subsequent to that transportation which brought them from their original position. 
Boulders of Primary Rock. 
The most southern part of the district where boulders of primary rock were noticed, was 
in the valley which leads from Vanettensville to Spencer in Tioga county ; they were of the 
smaller size, and composed of granite. They are not remembered to have been seen south 
of two miles below the village of Cortland. In Shed’s ravine, south of Truxton, there is 
quite a large one, being from four to five feet in diameter. North of the village, and in the 
neighborhood, there are a number, but of a smaller size, all likewise of primary rock. They 
occur also near Preble. 
Boulders of the same kind are yet more numerous in the valley at the head of Otisco lake, 
on the road to Homer. A few appear near Spafford, towards the ridge, between the road and 
the lake; also on both sides of Skaneateles lake. 
Through Madison county, they are seen in numerous places on the hills and hill-sides, 
extending into Chenango county. One of the largest seen in this county is in the village of 
Peterboro’; it consists chiefly of white quartz, with a little white feldspar and garnet: it was 
the largest seen south of the Mohawk. 
Boulders are very numerous at the north end of Otsego county, being found on all its hills. 
They occur in profusion on the limestone terrace to the northeast of Cherry-Valley village, and 
the enclosures there are principally formed of them. They appear in many of the creeks in 
the valley, having fallen from a higher level. In the same situation, also, they are seen in 
many parts of Oneida county south of the Mohawk, as in the ravine back of Dr. Noyes’s near 
Hamilton college ; in Bridgewater valley, etc. etc. 
