DAVIS. — OUTLINE OF CAPE COD. 307 



recession from 1848 to 1888 was 128 feet, or 3.2 feet per annum. 

 The face of the cliff, whose average height is 50 or 100 feet, has 

 thus lost a total of 30,231,038 cubic yards, or 755,776 cubic yards 

 per annum. The bar south of Nauset, enclosing the north side 

 of Pleasant harbor, extended its length southward some distance in 

 the same period. The same author has made a detailed report on 

 the changes in shore line and anchorage areas of Provincetown harbor 

 in Appendix 8, U. S. Coast Survey report for 1891, with an elaborate 

 chart. 



K. Weule has, in his " Beitriige znr Morphologic der Flachkiisten " 

 (Kettlers Zeitschr. wiss. Geogr., 1891, VIII. 211-256), discussed Cape 

 Cod at some length (232-238). The tidal currents are regarded as 

 the most important factors in its shaping. A misunderstanding of 

 local conditions is implied when the author asks how " the narrow 

 mainland of uncompacted materials can remain intact in an exposed 

 situation, when even so resistant landmasses as rocky Nantucket and 

 Martha's Vineyard suffer great loss " (232). The present preserva- 

 tion of the Cape is ascribed to the beach sand, brought from the 

 shoals on the southeast by the flood tide. Weule follows Whiting in 

 attributing a greater age to the outer than to the inner side of Prov- 

 incetown peninsula (234). The existing mainland is regarded as 

 only a remnant of a great extent of drift land (233) ; this opinion 

 being taken from a report by A. Agassiz. 



A brief article of my own, describing " Facetted pebbles on Cape 

 Cod" (Proc. Bost. Soc. Nat. Hist., 1893, XXVI. 166-175), argued 

 from these evidences of teolian action that the plains of gravel and 

 sand were deposited under the air rather than under the sea. 



A " Report of the Trustees of public reservations on the subject of 

 the Province Lands" (Mass. Legislature, House, Pub. Doc. 339, 

 Feb., 1893, p. 6) states that "there is evidence that the tides and 

 waves have built one beach after another, each farther north than the 

 last, and that the so called Peaked hill bar is a new beach now in 

 process of formation." The report contains an elaborate map of the 

 sandy peninsula by J. N. McClintock, on a scale of about five inches 

 to a mile, with ten-foot contours. The manner in which the outer 

 beaches overlap the inner ones is very clearly shown. Five photo- 

 graphic illustrations present characteristic views of the dunes. 



A general work on coastal forms — " La geographic littorale " — 

 by J. Girard (Paris, 1895), briefly compares Sandy hook and the end 

 of Cape Cod, classifying them with spits formed by littoral currents, 

 but giving no specific description. 



