524 



OGILVIE 



does not represent a pene-plain, but is occasioned solely by the 

 attitude and resistance of the hardest rocks — the granites. The 

 softest rocks are the schists. These determine the course of 

 the rivers, and are near sea level, while the more basic igneous 

 rocks usually outcrop at intermediate altitudes. The eleva- 

 tions of intermediate hardness form knolls about 130 feet high. 

 There are no conspicuous glacial features. The drift is thin 

 and consists mainly of scattered bowlders. If any physiographic 

 work was done by the ice it was of the nature of excavation. 

 There are no deposits of sufficient extent to cause any changes in 

 drainage. Such lakes as exist are wholly or in part artificial. 

 Striae were found at the following localities and in the following 

 directions. The direction of ice motion was evidently nearly 



southward. 



Table I. 



Glacial Stria. 



Locality. 



Direction. 



Rock. 



Position on Map 1 



North end Adams Pond 



N.-S. 



Schist 



3°-4-3- 



West side Linekin's Bay on 









northern dike 



N. io° W. 



Diabase 



S4-3-3- 



Beside road 3^ miles south of 









North Edgecomb 



N. io° E. 



Gneiss 



x 3-3-4- 



Beside road 1 mile south of 









Edgecomb 



N. 5 E. 



Gneiss 



14. 7-3- 



Same road 1 mile farther south 



N. 5 E. 



Gneiss 



24.1.5. 



The fiord character of the coast of Maine is usually ascribed 

 to combined drowning and excavation by ice. The Boothbay 

 quadrangle offers no new evidence on these points. It is clearly 

 drowned, and ice excavation seems very probable; but there is 

 one feature that this history does not explain, and that is the 

 remarkable courses of the streams. As already mentioned it is 

 by no means uncommon for a stream to begin by flowing north, 

 to turn at right angles, and then after a short east or west course 

 to enter one of the southward draining estuaries. The most 

 conspicuous example is afforded by Adams Pond, Back River, 

 Oven Mouth and the lower Back River. Adams Pond is 



1 The figures in this column indicate the position on the map in the 

 manner described by Kemp, Bull. Geol. Soc. Am. XVI, p. 411. 



