1910.] INLAND-ICE OF THE ARCTIC REGIONS. 85 



studied the land margin of the isbhnk in North Greenland, all call 

 attention to the precipitous and generally vertical wall which forms 

 the ice face (see Plate XXVI, 5). As a result of shearing and over- 

 thrusting movements within the ice near its margin, as well as to the 

 effect of greater melting about the rock fragments imbedded in the 

 lower layers of the ice, the face sometimes even overhangs in a 

 massive ice cornice at the summit of the wall (see Plate XXVII, A).^'^ 



That to this remarkable steepness of the ice face as observed 

 north of Cape York there are exceptions, has been mentioned by 

 both Chamberlin and Salisbury, but Peary has also emphasized the 

 vertical face as a widely characteristic feature of North Green- 

 land. The recent Danish expedition to the northeast coast of 

 Greenland has likewise furnished examples of such vertical walls. 

 An instance where the ice face appears as a beautifully jointed 

 surface somewhat resembling the rectangular joint-walls in the 

 quarry faces of certain compact limestones, is reproduced from the 

 report of the expedition in Plate XXVII, 5.^^ 



Attention has already been called to the precipitous front, the 

 so-called " Chinese Wall," which Lieutenant Lockwood found to 

 form the land face of the inland-ice of Ellesmere Land — a face 

 which was followed up and down over irregularities of the land 

 surface, and whose height in one place was roughly measured as 

 143 feet (see Fig. 15, p. 75). 



From central and southern Greenland, on the other hand, we 

 hear little of such ice cliffs as have been described, and Tarr in 

 studies about the margin of the Cornell extension of the isblink^- 

 has shown that here the vertical face is the exception. ^^ The 

 normal sloping face as there seen is represented in Plate XXVIII, /i. 

 In following the ice face for fifteen miles, its slopes were here found 

 to be sufficiently moderate to permit of frequent and easy ascent 



™ Chamberlin, Jour. Geol, Vol. 3, 1895, p. 566. Salisbury, ibid., Vol. 4,. 

 1896, p. 778. 



^^ Gunnar Andersson, " Danmarks expeditionen till Gronlands nordost- 

 kust," Ymer, Vol. 28, 1908, pp. 225-239, maps and 7 figures. 



^' To the south of the upper Nugsuak Peninsula in latitude 70° 10' N. 



^R. S. Tarr, "The Margin of the Cornell Glacier," Am. Geologist, Vol. 

 20, 1897, pp. 139-156, pis. 6-12. 



