220 GEOLOGY OF THE THIRD DISTRICT. 



In the yellow-colored clay which underlies the swamp back of the village of Woodstock 

 in Madison county, the soil of which is muck or peat, the tooth of an elephant, the Elephas 



, was found in digging a ditch. Attention to this discovery was directed by Mr- 



Gerrit Smith and the Rev. Mr. Schofield of Peterboro', from whom fragments were received, 

 the tooth having separated into parts by exposure to the air and rough usage. This is the 

 only fossil which was seen, forming a part of the quaternary era, during the survey of the 

 district. A part of the tooth is in the State Collection. 



Sand. 



An immense deposit of fine yellow sand skirts the Primary region of the district ; com- 

 mencing at Boonville, and extending along Black river through Herkimer and Montgomery 

 counties into the first district, and appearing to be connected with the mass which overlies the 

 clay deposit between Albany and Schenectady. The localities where it appeared to be in 

 greatest amount, are in the neighborhood of Boonville ; in the northern part of the towns of 

 Russia and Norway ; from Salisbury comers to Brocket's bridge ; west and east of Lassels- 

 ▼ille ; west of Klip hill ; between Kingsborough and Fonda's bush ; and near Galway. 



The hills southwest of Little-Falls are of the same kind of sand, and have already been 

 adverted to ; but no mention was made of finding upon the top of one of the highest near the 

 quarry, large pebbles of primary rock, red and grey sandstone, limestone, etc., and having near 

 its base a boulder of rubblestone, which probably came from its summit. These facts corres- 

 pond in some measure with observations made by the Geologist of New-Hampshire, page 46, 

 Report of 1841. "The granitic sand is heaped up in hills from Durham to Lee, some of 

 " which are of tolerably regular conical shape, and are elevated from two to three hundred 

 " feet above the general level of the surface. On the summit of one of these elevations, oc- 

 " curs a numerous group of erratic boulders of sienitic granite, remarkable for their isolated 

 " situation and great size." 



The existence of the boulder of rubblestone at the point noticed, is a fact of some moment 

 in the history of the valley, there being no layer of its thickness west of Montgomery county. 

 The same kind of rock, but in smaller masses, is found in considerable number upon the 

 top of the uplift on the south side of Little-Falls, and have all certainly been carried from 

 east to west, where they are strewed over the surface in great profusion. 



Boulders. 



Though the term boulder would imply a mass of rock somewhat round, that has been 

 removed from its original position, the word is applied to all masses whether round or angular, 

 the size and the removal to a distance from its native place being the chief characteristics. 

 Two causes are known to produce the rounded appearance which they often present : the first 



