106 



HOBBS— CHARACTERISTICS OF THE 



[April 22, 



tion with the study of the strength and direction of the wind over 

 the snow surface. All minor hummocks and ridges of this nature 

 are included under the general term sastrugi (see Fig. 31). 



The student may learn much concerning their form within the 

 Antarctic regions from examination of the many beautiful photo- 

 graphs recently published by the Royal Society in connection with 



Fig. 31. Sastrugi on the inland-ice of North Greenland (after Peary). 



the British Antarctic Expedition. ^° On Plate 92 of this collection, 

 sastrugi are shown which were originally laid down in " elongated 

 domes " and " crescent hollows," but which on account of change 

 in the wind direction the drifting snow granules have cut away 

 both on the soft surface and in the harder deep layers. As a result 

 of this erosion cross flutings have been superimposed upon the 

 original forms. 



^° National Antarctic Expedition, 1901-4. Album of photographs and 

 sketches (with brief descriptions, Ed.), London, 1908. 



