260 GLACIAL GRAVELS OF MAmE. 



into the Great Ossipee River near Kezar Falls. A line of glacial gravels 

 extends from East Brownfielcl along The Notch to Kezar Falls. In the 

 midst of The Notch are three ponds bordered by plains of glacial gravel 

 rising tip to 20 or more feet above the water. It is difficult to account 

 for lake basins being excavated by boiling springs in a mass of coarse 

 composition such as gravel, cobbles, and bowlderets. These lake basins 

 must have been deposited in substantially their present shapes by the 

 glacial river. This is an interesting divergence from the ordinary type 

 of osar-plain. Here, as in numerous other places, we find the broad osar 

 and the tracts of reticulated ridges passing into each other by degrees. 



I shall sum up, briefly, some of the general features of the glacial 

 gravels of this region. 



Seldom, and then only for a short distance, do the gravels take the 

 form of a single ridge with arched cross section, like the osars of eastern 

 Maine. Toward the north these gravels usually take the form of a broad 

 osar, i. e., a rather level-topped plain from a few rods up to one-fourth or, 

 in a few cases, one-half mile wide. Farther south, at elevations below 600 

 and above 230 feet, the gravels expand into plains of reticulated kame 

 ridges up to 3 or 4 miles in breadth. At about 230 feet the reticulated 

 kames pass into the great level delta-plains. These show clearly the hori- 

 zontal classification of sediments characteristic of deltas, and sand plains 

 pass by degrees into marine clays. Here and there small delta plains are 

 found in the courses of both osars and reticulated kame plains. Many of 

 these are far above the contour of 230 feet and were probably deposited 

 in glacial lakes. 



One who studies the glacial gravels only on southern slopes where the 

 rivers now flow in the same direction and in the same valleys as the glacial 

 rivers, will find it difficult to distinguish between the sediments of the two 

 kinds of rivers in such situatioiis. He may come to attribute all the allu- 

 vium to the rivers of the so-called Champlain period, and may even doubt 

 the existence of glacial rivers, at least as agents for depositing alluvium so 

 much resembling fluviatile drift. Such skepticism will be permanently 

 removed by a few days of exploration in the region now under considera.- 

 tion. Here he will see these long lines of sand, gravel, and coarser sedi- 

 ment go up and over the steep hills. Here can be seen how often they 

 reject valleys of natural di-ainage and instead climb hills 200 feet or more 



