BYRD ANTARCTIC EXPEDITION — GOULD 239 



graduall}^ to 895 feet above sea level at 50 miles, and we were not yet 

 on top of the hill. We had but crossed diagonally the northern end 

 of a great gentle bulge in the shelf ice. Its axis trended southeast 

 to northwest, and we estimated it to be at least 50 miles long. We 

 conservatively judged that this hill must attain a height of at least 

 1,000 feet at its highest point. Except for this bulge there are no 

 significant changes in level of the shelf ice between Little America 

 and some 15 to 20 miles from the foot of the mountains. It presents 

 on almost every hand a featureless plain of dead monotony. 



There seems little question but that this hill indicates a place 

 where the shelf ice is held up and back by land. Crevasses to the 

 west of it and even to the southwest where we came down from its 

 slope onto the general level of the shelf indicate that there is some 

 movement of the ice about it. 



THE CREVASSED AREA 



The second area of more than passing interest in this first leg of 

 our journey was the crevassed region between latitudes 81° 10' and 

 81° 17' S. Amundsen described an eerie passage through this region, 

 and both the supporting party and we of the geological party often 

 found ourselves holding our breath as we threaded our way through 

 the crevasses. As we approached this region from the north we (irst 

 came upon old crevasses long since dead and now filled with snow 

 and ice. Next we found ourselves in a region of partially filled cre- 

 vasses which here and there expanded into circular depressions from 

 5 to 15 feet across. They were not unlike symmetrical sink holes 

 in appearance. A few haycock-shaped mounds were noted here, but 

 their number increased farther south where the crevasses gave evi- 

 dence of being much younger. Some of these haycocks had steep 

 sides and a beehivelike configuration. These were generally thin- 

 skinned; and some could be broken with a ski stick to reveal a great 

 chasm below. Apparently the circular sink-holelike depressions 

 represent the site of these thin-skinned haycocks. The faulted-dome 

 type of haycock with a flatter, more conical profile was present in 

 larger numbers than the beehive type. 



On the southern edge of this region we found newly formed cracks 

 from a few inches to more than a foot in width. Camped here for 

 the night, we soon became aware that all was not quiet around us. 

 The ice was cracking about and under us, sometimes with detonations 

 like distant cannon and again with sharp reports like rifles fired close 

 by. Occasionally the tent itself would be jarred as the ice snapped. 

 I timed these reports with my stop watch and found that they aver- 

 aged one a second for about 20 minutes, when I fell asleep. When 

 I awoke three or four hours later and again listened, I was amazed 



