234 BOARD OF AGRICULTURE. ' 



the pebbles are elongated and flattened, and entirely siliceous. 

 They illustrate the different phases of conglomerate mctamorphism 

 more finely than the example in Washington county adduced last 

 year. Gay's Island, which is a large island connected with the 

 main land during low tide, is also composed of mica schist. 

 Whether the St. George's Islands or- any in Muscongus bay have 

 a similar basis, we have no means of ascertaining. To learn the 

 geological character of these and all the islands scattered along 

 the coast of Maine will require a considerable time with a sail boat. 

 Adjacent to the granite in St. George and South Thomaston is a 

 narrow belt of obscure mica schist, which really belongs to the 

 deposits of this age, although the paucity of our observations there 

 and the concealment of the ledges by drift makes our knowledge of 

 them very limited. It is at least a mile in width where we crossed 

 it after leaving the quartz rock on West Keag river. Its relations 

 to the adjacent rocks are given in Fig. 37. 



We cannot find much that will interest in the details of the dis- 

 tribution of the gneissic rocks of the third area specified, or that 

 including the north part of Gushing, Warren, etc., to Belfast. The 

 rocks in Gushing are mostly distinct gneiss but of uninteresting 

 appearance. Where the rocks of this group first show themselves 

 on the road to Gushing from Thomaston, they consist of gneiss and 

 hornblende rock with a little granite. The strata are very much 

 plicated. A synclinal axis runs along near the eastern shore as 

 far south as the rock extends. In the north-west part of Gushing 

 and the north part of Friendship, the dip is uniform, and the 

 gneissic character of the rock prevalent, interspersed with numer- 

 ous granite veins. 



In the south part of Warren, Mr. Peter Wallace's house stands 

 upon the eastern border of the gneiss. About South pond the dip 

 is variable, and the gneiss alternates with granite, often very beau- 

 tiful. The uniformity of the gneissic rocks in the other parts of 

 Warren is relieved by the occurrence of occasional beds of sacca- 

 roid azoic limestone. 



In Camden there is greater variety. Between Simonton's Gom- 

 ers and the Harbor the rock is a handsome variety of the mica 

 schist, sometimes suitable for paving stones. On Roach hill and 

 westwardly the gneissic type predominates. A section from In- 

 graham's Corner to Union shows both mica schist and gneiss with 

 several folds in the strata. This road passes by a pond, on the 



