30 SURFACE GEOLOGY. 



than the corresponding terrace opposite, on which Newbury is built. 

 This difference may be partly due to the fact that here was one of the 

 principal outlets of the melting ice-sheet that continued to cover Moosi- 

 lauke and the high water-shed after it had withdrawn from the Con- 

 necticut valley. East from North Haverhill, where there are now only 

 insignificant brooks, we find an abundance of sand and coarse gravel 

 which came from this source. It is disposed in irregular slopes, in some 

 portions mounded or ridged, and rising in about one mile 250 feet, beyond 

 which the same materials extend nearly level to French pond. Taking 

 the road to Haverhill town-house, we pass a ridge of coarse gravel or 

 slightly modified drift, which rises from 40 to 100 feet above the village. 

 North-east from this there is a nearly level plain of fine alluvium, with 

 beds of clay. A short distance farther east we come to a sand ridge, 

 which extends about a half mile along the road, rising 80 feet by a gentle 

 slope, and then abruptly 75 feet more, like the face of a terrace, to a level 

 plain on which the town-house stands, 247 feet above North Haverhill 

 and 752 feet above the sea. This plain, its western steep slope, and the 

 first ridge below are all of sand, with none of the coarse gravel charac- 

 teristic of kames. Similar deposits of fine material reach for a half mile 

 on each side of this road, sometimes in level plains of small extent, but 

 generally in varying slopes, by which they are continuous from the town- 

 house to the upper terrace of the river. 



The remainder of the way to French pond is comparatively level, being 

 at first a plain of stratified, coarse-grained sand, which extends north one 

 half mile to the brook; thence, for a mile and a half farther, sand or 

 coarse rounded gravel extends along the road and on its east side as far 

 north as to French pond. Immediately about this pond the modifying 

 action of water is not apparent, but the surface is composed of heaped 

 and ridged morainic drift, over which the road passes. This material is, 

 however, in the main, level; with irregular hollows and depressions of 

 only ten to twenty feet. Its rock-fragments are angular, but small in size, 

 seldom exceeding two feet, A coarse morainic ridge extends more than 

 a mile on the east side of this level alluvial valley, with a height about 

 125 feet above it, while on the west rises the precipitous face of Brier 

 hill. Three miles south-east are the serrated mountains which extend 

 north from Owl's Head; and nine miles south-east is the high, massive 

 ridge of Moosilauke. 



