346 
Culver—The Erosive Action of Ice . 
Rev. J. Clifton Ward 9 , speaking of the tarns of Cumbria, be¬ 
lieves them to be of ice origin for reasons precisely like those 
given by Ramsay long before. 
Isaac Kinley 10 thinks glaciers have excavated the basins of 
large numbers of our North American lakes. 
Prof. N. H. Winchell * 11 thinks that Green Bay and Great Bay 
de Noquet were excavated by ice. 
Dr. Robert Bell 12 , of Canada, thinks Great Slave lake, Atha- 
baska, Winnipeg, Georgian Bay and Ontario lakes were exca¬ 
vated by post-tertiary glaciers. 
Rev. J. G. Bonney 13 does not believe that any of the great 
alpine lakes were primarily formed or have undergone any 
great secondary modification by glacial action. He would ac¬ 
count for the lakes by local crust movements. 
Prof. J. W. Judd 14 does not believe that any basin that can 
be called a lake at all, can be attributed to glacial action as a 
primary cause. 
Mr. Carr 15 said: “The moulding power of ice upon hard granite 
possessing a strong physical structure, is comparatively slight. 
In such regions, glaciers do not so much mould and shape, as 
disinter forms already conceived and ripe. ” 
Prof. Whitney in “Climatic Changes’’ said: 
“The most important work of a glacier is the scratching 
and grooving of surfaces . . . the only glacial lakes are those 
where pre-existing valleys have been closed by morainic mat¬ 
ter. ” 
Hugh Miller said, that if glaciers can excavate at all, they 
can more easily enlarge a lake than start one. 
Dr. F. Pfaff 16 after experimenting on the Aletch glacier, ar¬ 
gues against the theory of the formation of valleys by glacial 
erosion. 
10 Pop. Sc. Monthly, July, 1887. 
11 Am. Jour. Sc., 3d series, vol. 2, p. 17. 
12 Quoted by Pop. Sc. Monthly, July, 1389. 
13 Quarterly Jour. Geol. Soc., vol. 25, pp. 479-489. 
14 Geol. Mag., dec. II., vol. 3, pp. 523-525. 
15 Overland Monthly, May, 1874. 
16 Pogg. Ann., vol. 151., pp. 325-333. Sitsungsberichte Phys. Med. Soc. 
Erlangen, Heft VI, Seiten 34-44. 
