MODIFIED DRIFT ALONG MERRIMACK RIVER. 89 



kames from west to east. South from this the space between the ridges 

 has been mainly filled with alluvium, forming a plain upon which the 

 position of the kames is easily traced by their lines of coarse gravel. 

 Occasional boulders, apparently brought by floating ice, lie on the sur- 

 face of this plain. One of white quartz, six feet long, has thus travelled 

 more than two miles from its parent ledge, which was probably the Pin- 

 nacle. 



The course of the kames now turns eastward and then westward at 

 the end of a mile, conforming to a bend in the valley. At the north this 

 curve consists of a single low ridge, which is in large part composed of 

 angular rocks up to one or two feet in size, lying between the road and 

 the river. Where it turns to the south-west, opposite Martin's Ferry, we 

 have a broad gravel hill, in which also many of the stones are angular, 

 while other portions are water-worn. Thence for two miles southward 

 the kames have been wholly carried away by the river, which has its 

 channel directly in the line of their course. 



On the east side of the river this series may be represented in the high 

 plain one mile north of Martin's Ferry, which has irregular ridges and 

 hollows, and is composed of gravel with pebbles six inches to one foot 

 in diameter; but a large area of similar gravel, extending thence to the 

 north-east, seems to be clearly a tributary deposit. An undoubted rem- 

 nant of the series occurs half a mile south from this station, in a coarse 

 gravel deposit, showing oblique and irregular stratification, which has 

 been excavated for railroad ballast. Occasional angular boulders, three 

 to six feet in size, which must have been brought by floating ice, were 

 noticed in the same terrace. 



In Manchester a fine display of these kames begins at the west side 

 of the river road, a mile and a half above Amoskeag bridge, and their 

 greatest development in the whole series is thence south-west to Piscata- 

 quog river, where they cover an area two miles long by one fourth to 

 half a mile wide, closely adhering to the west side of the widened valley. 

 We find here as many ridges as can well occupy this space, all lying in 

 the same course, which is that of the series, and having a comparatively 

 uniform height. Some of them probably extend almost the entire length 

 of this area, while others are short or broken by gaps. Their material is 

 principally water-worn gravel, sometimes as fine as prevails in the Con- 

 VOL. Ill, 12 



