388 THE VOYAGE OF THE 'DISCOVERY' [Sei-i. 



signs of obstacles ahead. Here and there in the snow surface 

 rose a dome-shaped mound of blue ice, and beyond these we 

 could see little heaps of rubble. It behoved us to be cautious 

 if we would avoid injury to our sledge-runners. 



The ice-mounds deserve notice; they are a very typical 

 form of disturbance on the surface of any glacier, but are 

 probably rarely so well developed as we saw them. They are 

 caused by surface melting, the water freezing again below the 

 ice, when the expansion on regelation gradually lifts the surface. 

 To stand amongst a number of these domes is very impressive, 

 especially when they are uniformly rounded. They rise but a 

 short distance before they are cracked in all directions on top, 

 and the cracks gradually open into broad, deep fissures. We 

 found domes as high as seven and eight feet in this region, 

 and saw mounds which in attempting to rise further had lost 

 the dome form and stood up like irregular- shaped craters. 

 It was on the surface of one of these, far from the land, that 

 Mr. Ferrar found a large quantity of crystals of sodium or 

 magnesium sulphate. I am not chemist enough to suggest a 

 reason. 



■ • '■September 27. — Started with promise of a fine day, tem- 

 perature — 46 . Soon after, the sky became overcast and the 

 temperature rose. The travelling changed altogether in char- 

 acter j the ice-mounds grew thicker, and reached a height of 

 eight to ten feet, with broad, ugly cracks all over them. Later 

 they seemed to assemble in ridges running more or less east 

 and west, and hence right across our tracks ; the dogs could 

 make no show of crossing them, so we had to turn outwards 

 in hopes of getting better travelling. Instead of this it got 

 worse, and after lunch we passed into a turmoil of torn and 

 twisted ice, forming ranges of hillocks twenty and thirty feet 

 high, sometimes rounded on top and sometimes rising in sharp 

 ridges. The higher parts were swept clear of snow and showed 

 bare blue ice, whilst in the hollows the snow lay in high, hard 

 sastrugi ; the contrast was plain even in a bad light. 



Travelling now became a regular scramble up hill and 

 down dale. The dogs did not appreciate it at all; they 



