THE LONG ISLAND TERMINAL MORAINE. 73 



References to the alternative opinion, that the englacial drift was of 

 small amount, and that the drift transportation was mainly subglacial, 

 are as follows : ■ 



James Geikie : The Great Tee Age, second edition, 1877, pp. 415, 416, etc. 



T. C. Chamberlin, U. S. Geological Survey, Third Annual Report, for 1881-'82 

 (published 1883), p. 297, earliest proposing and defining the term Englacial or 

 Superglacial Till. " Boulder Belts distinguished from Boulder Trains— their Origin 

 and Significance," Bulletin, Geographical Society of America, vol. i, 1890, pp. 

 27-31. " The Nature of the Englacial Drift of the Mississippi Basin," Journal of 

 Geology, vol. i, 1893, pp. 47-60. "The Horizon of Drumlin, Osar and Kame 

 Formation," Journal of Geology, vol. i, pp. 255-267 ; and editorial remarks, p]3. 

 521-524. 



R. D. Salisbury: Geological Survey of Xew Jersey, Annual Report for 1891, pp. 

 65-83 ; ditto for 1892, pp. 38, 39, 50-59. American Geologist, vol. x, p. 219 ; vol. 

 xi, p. 243. 



KaMES forming the TERMINAL MORAINE OF LONG ISLAND EASTWARD 



FROM ROSLYN. 



The outermost moraine southeast of New York and south of New 

 England, explored by the writer fourteen years J^go, is a conspicuous 

 series of hills called " the backbone of Long Island," stretching along 

 the entire length of this island, beyond which the same moraine reap- 

 pears farther east in Block island, Martha's Vineyard, and Nantucket.* 

 Through a distance of more than seventy-five miles on Long island, from 

 Roslyn east to Napeague at the western end of the peninsula of Montauk, 

 this line of hills, though continuous in a narrow and mostly simple 

 series, doubtless accumulated at the margin of the ice-sheet, differs re- 

 markably from any other equally prominent and prolonged portion of 

 any moraine among the many which have been traced and mapped in 

 the northern United States and southern Canada. Elsewhere usually 

 the morainic drift is till, or at least, if it consists partly or sometimes 

 almost wholly of stratified gravel and sand, it yet has frequent portions 

 more or less filled and overspread with bowlders, which indeed are com- 

 monly ten to twenty or even fifty times more abundant there than in 

 and upon adjoining lower till areas'. For nearly twenty-five miles, from 

 the Narrows east-northeast to Roslyn, this moraine is composed of till, 

 or the unstratified glacial drift, with plentiful bowlders, and rises in 

 irre^^ular undulatino; hills from 100 to 250 feet above the sea. But from 

 Roslyn to Napeague the accumulation of morainic till, if any exists in 

 the nucleal part of the hill range, is almost completely enveloped and 

 concealed by fluvial deposits. The moraine there is a series of very 



* Am. Jour. Sei , third series, vol. xviii, Aug. and Sept., 1879, pp. 81-92, 197-209. 



