MODIFIED DRIFT ALONG CONTOOCOOK RIVER. 113 
the channel here may have been formed by the erosion of the river. A 
third of a mile from this railroad station, several parallel kames are found 
extending nearly east and west between the highway and the outlet from 
Rolfe’s pond. These are composed of the usual water-worn gravel, with 
pebbles up to one foot in size, and form ridges and mounds 25 or 30 feet 
high and 60 feet above the river. 
In the remaining ten miles of its course the Contoocook is almost con- 
tinuously bordered by extensive low plains, seldom exceeding 30 feet 
above the river, with occasional areas of interval, but no kames were 
seen. On the south side of the river, below West Hopkinton, portions of 
these plains are 50 feet above the river; and on the north side the same 
height is reached by a delta-like deposit where the outlet from Clement 
pond enters the alluvial area. At Contoocookville the alluvium is in- 
terrupted by low areas of till or ledge, that upon the north side being 
quite low and scarcely higher than the plains, which seem at the edge of 
the village to extend across it. Thence eastward low sandy plains, from 
15 to 25 feet above the Contoocook, extend nearly level for eight miles to 
the Merrimack river. Their greatest expanse is in the north-east part of 
Hopkinton, the north-west corner of Concord, and the south edge of 
Webster, where they cover an area three miles long from north to south 
and nearly two miles wide. This at the north consists partly of swampy 
land, slightly depressed, and with no outlet for drainage. Warner and 
Blackwater rivers, which are tributary to the Contoocook in Hopkinton, 
are bordered by considerable alluvial deposits, the former in Warner and 
the latter in Salisbury. 
Three miles above its mouth the Contoocook is enclosed by hills with 
only a narrow alluvial margin. The proper continuity of its plain is here 
along the Concord & Claremont Railroad, with a hill between it and the 
river, east of which the plain is wide, lying principally on the south side 
of the Contoocook river, at a height of 125 feet above the Merrimack. 
Below Contoocookville the river has a height of about 355 feet above the 
sea nearly to Fisherville, where it descends rapidly to its mouth, which is 
249 feet above the sea. 
We will next consider the course of events in the Champlain period, of 
which these deposits of modified drift bear witness. 
VOL. UL 15 
