CAPE COD GEOLOGY 



243 



in 1842. 1 This map was revised in 1860 by H. F. Walling 2 under authority of 

 the legislature. The map of Cap Cod published in 1871 is based on surveys 

 of Barnstable County made by Walling in 1858, but includes corrections of 

 the coast line supplied by the Coast Survey chart of 1857, 



DESCRIPTIVE GEOLOGY 



(See Plates 1 and 2) 

 Earlier Reports 



Captain John Smith made perhaps the first report on the geology of south- 

 eastern New England, including Cape Cod, in these words: "From 43. to 41. 

 and a half, an excellent mixed coast of stone, sand and clay 3 . . . " No more 

 complete account of the geology of Cape Cod was published until the report 

 of President Edward Hitchcock, undertaken for the Commonwealth, appeared 

 in the publications of the State survey. 4 One result of these official surveys 

 was a geological map of the State, which, in the issue of 1841, represented Cape 

 Cod as "diluvium," a term having the same meaning as Pleistocene in modern 

 geological literature when limited to the glacial deposits. The final report ap- 

 peared after the publication, in the same year, of Louis Agassiz's famous ' 'Etudes 

 sur les Glaciers," which led Hitchcock to suggest, in a postscript of his report, 

 the possibility of glacial action on Cape Cod. Hitchcock had already, in the 

 body of his report, so he states, called in the aid of ice to explain the mounds of 

 gravel and sand. In the application of the glacial theory of Agassiz to the Cape 

 Cod district the question arose whether "the whole of Cape Cod is nothing 

 but a vast terminal moraine, produced by a glacier advancing through Massa- 

 chusetts Bay, and scooping out the materials that now form the Cape." He 

 then goes on to state that the moraines at Plymouth and Truro would form 

 a part of the lateral moraine, and that probably most of Nantucket and Marthas 

 Vineyard might be regarded as moraines of the same glacier when it extended 

 farther south. 5 



He considered the laminated clays on the Cape a strong obstacle to this hy- 



1 Published by Morse and Breese. Engraved on copper by George G. Smith. Boston, 1842. 



2 H. F. Walling and O. W. Gray, Official topographical atlas of Massachusetts, 1871; Plates 70-71, 

 Barnstable County, with insets of Dukes and Nantucket counties. Scale 2J miles to an inch. 



3 Captain John Smith, New Englands Trials, London, 1622, 2d ed. Reprinted in Everyman's Library, 

 Chronicles of the Pilgrim Fathers (1910), p. 245. 



"Edward Hitchcock, Report on the geology, mineralogy, botany, and zoology of Massachusetts, 

 Amherst, 1833, 2d. ed., 1835. Report on a re-examination of the economical geology of Massachusetts, 

 Boston, 1838, 139 pages, House Doc. No. 52. Final Report on the geology of Massachusetts, Amherst, 

 Northampton, 1841, 4 to 831 pages. 



5 Edward Hitchcock, Final report on the geology of Massachusetts 1841, p. 9a, postscript. 



