212 H. L. FAIRCHILD POST-GLACIAL UPLIFT OF N. E. AMERICA 



aneroid, gives the height of the highest beacli near tlie outer coastline as about 

 225 feet for the region east of Penobscot Bay and 230 feet for the region be- 

 tween that bay and the Kennebec River" (page 49). 



". . . Since the height of the sea rapidly diminishes southward in New 

 Hampshire and Massachusetts, it appears that tlie average elevation of the 

 sea on the Atlantic coast south of Nova Scotia was greatest in the region lying 

 between Portland and the Penobscot Bay, or perhaps near the mouth of the 

 Narragaugus River" (page 50). 



A glance at the map of isobases will show that the figures of Stone for 

 the marine submergence on the Maine coast are in practical accord with 

 the new data of the map. He underestimates the difference in uplift be- 

 tween the shores east and west of Penobscot Bay, but correct!}^ deter- 

 mined the inclinations, as shown in the last of the above quotations. 



Concerning the interior sand-plains, he writes in his smnmar}^': 



"4. Elevation of marine deltas.— The deltas of the interior at 300 to 350 feet 

 are now interpreted by me as marine, but possibly this point may be disputed. 

 They certainly do not bear such relations to the fossiliferous clays as the 

 deltas nearer the coast. But sheets of clay and sand are found extending 

 from the deltas up to considerablj' higher elevations, and therefore under no 

 conditions do the deltas mark the highest level of the sea. . . . The higher 

 deltas are more than 100 feet above the highest fossil thus far found. . . . 

 Both together constitute valuable collateral evidence of the presence of the 

 sea in the interior valleys, hut do not give the extreme limif (page 482). 



"Some of these basal fine sediments pass above any level of the sea that now 

 appears admissible, . . . rememliering that the subsidence in northwestern 

 Maine ivas th7'ee or four times that of the coast, or, rather, that the postglacial 

 elevation has been such" (page 485). 



"While we do not know the amount of early glacial subsidence, we do know 

 approximately the amount of postglacial elevation. I assume that this eleva- 

 tion has been about three times as great in northwestern Maine as at the outer 

 coastline" (page 486). 



Stone's "assumption" of the relative uplift was based on good observa- 

 tion and correct philosophy. The isobase of 800 feet along the northwest 

 boundary of the State is about three times the elevation of the portion of 

 the coast which he describes, or four times that of the eastern coast. 



In 1889 Professor Shaler published his description of Mount Desert 

 (57). His long experience in the study of shorelines and wave action 

 was applied in the work on the uplifted beaches on the island, with the 

 conclusion that evidences of wave-work appeared up to a height of 1,300 

 feet (page 1032). His description of the features proving recent sub- 

 mergence are given with perfect confidence, and appear conclusive to the 

 reader, for heights up to 250 or 300 feet (pages 1015-1022). Above tliis 

 altitude his statements arc qualified and the explanations and conclusions 



