8 1 6 Goldth wait — Tm< nty-Foot Terrace ami 



south of the pivot line in Laaland (p. 318)? The supposed 

 recent subsidence in eastern Massachusetts, as recorded in salt- 

 marsh structure, suggests such a possibility.* Further study 

 alight even indicate that the underlying forest beds along the 

 coast from Massachusetts to the Bay of Fundy are to be cor- 

 related with an uplift of the Saint Lawrence valley, instead of 

 with a subsidence. Until the Micmac terrace is traced around 

 the Gaspe peninsula, and southward towards the Bay of 

 Fundy, presumably down to sea level, as Broegger has traced 

 the Littorina shoreline, no satisfactory correlation of the sub- 

 merged stumps and the salt-marsh structure with the coastal 

 movements in southern Quebec can be made. 



(b) What, movement, if any, is now. taking place along the 

 coast? In Scandinavia, as we have seen, Broegger concludes 

 that neither uplift nor subsidence has occurred during the last 

 2400 years. The best evidences bearing upon this question 

 appear at present to be contradictory. On the one hand, the 

 peculiar structure of the salt marsh on the New England coast 

 has been accepted by some as proof of a continuous downward 

 movement of the coast since the underlying forest beds were 

 first submerged, extending to the present time.f On the other 

 hand, the fact that West Beach at Nantasket, whose age is 

 estimated as probably 2000 or 3000 years and certainly not 

 less than 2000 years, has a crestline altitude which accords with 

 that of the modern beach behind which it lies, seems to show 

 that for the last thousand years, at least, there has been no 

 change of level in eastern Massachusetts.^; The solution of 

 this problem is closely connected with that of the behavior of 

 the coast during the Micmac stage, since the same movement 

 may have aided the waves to cut back the Micmac cliffs as 

 drowned the forests or aided in the upward growth of the salt 

 marshes. Other alleged evidences of modern costal move- 

 ments, such as human testimony and change in altitude of 

 bench marks with reference to mean sea level, § are either con- 

 tradictory or open to a different interpretation. 



It might seem that the weak character of the modern beach, 

 along the south side of the Lower Saint Lawrence, would 

 indicate that the present movement, if any, is an emergence ; 

 because if there was a subsidence, wave action would be more 



* See papers cited above, by C. A. Davis. His mention, on p. 21 of Bulle- 

 tin No. 376. U. S. Geological Survey, of the occurrence in some localities of 

 salt-water pect below fresh-water peat, "indicating a slight uplift of the 

 coast previous to the subsidence which is still in progress," suggests a coun- 

 teroscillation on the Maine coast during the Micmac stage. 



t Papers by C. A. Davis and H. H. Baldwin, already cited. 



i D. W. Johnson and W. G. Reed, Jr. Op. cit., pp. 187-188. 



§ R. A. Daly: op. cit., pp. 261-262, and J. W. Dawson: Acadian Geology, 

 p. 31, and J. R. Freeman: Submergence of land and harbor bottom. Report 

 of Commissioners on the Charles River Dam, at Boston, Mass., 1902. 



