Febkuaey 6, 1903.] 



SCIENCE. 



221 



leads to the conclusion that the Green 

 River Tertiaries are not simply the con- 

 tinuous deposits of a single large lake, but 

 that they are the deposits of man^'^ succes- 

 sive shallow and fluctuating lakes of mod- 

 erate area combined with the deposits of 

 niunerous aggrading streams. 



A Highly Viscous Eruption of Ehy elite: 

 G. K. Gilbert, U. S. Geological Survey. 

 A butte of rhyolite in western Utah il- 

 lustrates the viscosity of acid lavas, and 

 thus helps to sustain the theory of Button 

 for the dynamics of eruption. 



Physiographic Belts in Western New York: 

 G. K. Gilbert, U. S. Geological Survey. 

 The physiographic belts recognized by 

 Lincoln can now be studied in part with 

 the aid of contour maps. South of the 

 drumlin belt is a zone of great glacial ero- 

 sion in which the aspect of the land was 

 revolutionized by ice sculpture. It is lim- 

 ited southward by a great moraine, beyond 

 which the upland drainage is pre-glacial, 

 and in which the glacial modification of 

 hill forms diminishes rapidly to the gla- 

 cial boundary. 



Some Shore Features of Lake Huron: M. 



S. AV. Jefeerson, Ypsilanti, Mich. 



This paper reviewed the shore featiires, 

 such as dunes, beaches old and new, town 

 sites and river erosions, at Kincardine, 

 Ontario, with regard to Kincardine's posi- 

 tion nearly 100 miles north of Gilbert's 

 isobase line. Comparison was made with 

 points to the south of the same line, as 

 Muskegon. Kincardine is regarded as 

 possessing a lake and bar separating it 

 from Lake Huron, modified in a manner 

 appropriate to an uplift of the smaller lake 

 bed to a height of about 70 feet above the 

 great lake, with resulting elevated beaches, 

 deeply cut stream valleys, limited dune 

 sand and increased river sediments. 



The Topographic Work of the Geological 

 Survey in Northern Canada: Robert 

 Bell, M.D., Acting Director Geological 

 Survey Department, Ottawa. 

 Previous to the confederation of the 

 Canadian provinces in 1867, and the sub- 

 sequent acquisition by the Dominion of the 

 other British possessions in North America, 

 including British Columbia, the territories 

 of the Hudson Bay Company, the Labra- 

 dor peninsula and all the islands lying 

 north of the mainland of North America, 

 the operations of the Canadian Geological 

 Survey were confined to the southei'n parts 

 of the areas which now constitute the prov- 

 inces of Ontario and Quebec. Since con- 

 federation, however, the attention of the 

 department has been directed to surveying 

 these vast, newly acquired territories and 

 the regions which have been added to On- 

 tario and Quebec. These tracts were en- 

 tirely unsurveyed and only partially ex- 

 plored, the main geographical features 

 alone being roughly indicated on the maps. 

 The subdividing of the fertile lands of 

 Manitoba and the Northwest Territories 

 was performed by a different department, 

 and its work added little to the knowl- 

 edge of the topography of the country. 

 The fieldmen of the Geological Survey 

 have been the pioneer surveyors of the 

 natural features of the vast regions which 

 constitute half the continent. In order 

 to map out the rock formations, the geolo- 

 gists found it necessary to make topograph- 

 ical and geological surveys simultaneously. 

 Fi'om their long experience in these opera- 

 tions, they have been able to do this work 

 rapidly and well, and the object of this 

 paper was to show the astonishing amount 

 of accurate geographical work which has 

 been accomplished by a small number of 

 devoted men with very limited means at 

 their disposal. 



