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THE NATIONAL GEOGRAPHIC MAGAZINE 



Photo by L,awrence Martin 



A GREAT GROOVE CUT IN HARD ROCK BY A GLACIER AS IT ADVANCED: PORT DORAN, 



HARRIM AN ElORD 



work in the study of the submarine to- 

 pography produced by glacial sculpture 

 and deposited in a fiord. On that par- 

 ticular day we made only 29 soundings, 

 but most of them were deep ones and one 

 of the party calculated that we had 

 wound up five miles of wire during the 

 day. 



As we looked up at Mt. Gilbert, 10,194 

 feet, on the way to camp that night, we 

 imagined an equal mountain placed on 

 top of it and over half a third one, think- 

 ing what it would have meant if we had 

 been on top of such a 26,000- foot peak 

 with a 20-pound lead at the base and had 

 had to wind it up with our small hand 

 reel all at once instead of in 500-1,400 

 foot lengths. Then the day's work 

 seemed larger, especially as we had dis- 

 covered an invisible moraine below sea- 

 level, together with two submerged hang- 



ing valleys, and had located an uncharted 

 rock and made a 22-mile longitudinal sec- 

 tion and two cross-sections of a wonder- 

 ful glacially sculptured fiord. 



Our other soundings revealed similar 

 groups of results. The depths of water, 

 as near the fronts of the several large 

 tidal glaciers studied as we dared ven- 

 ture in our launch, varied from 90 feet 

 in the case of Harriman Glacier to 636, 

 600, and 555 feet near Harvard, Colum- 

 bia, and Nunatak glaciers, respectively. 

 This shows that none of these glacier 

 ends could be afloat, for the visible 200- 

 300-foot ice cliff, if floating, would have 

 six or seven times that depth below sea- 

 level, and in no case is the part of the 

 fiord near the glacier deep enough. 



We made many other longitudinal and 

 cross-sections of inlets in Prince William 

 Sound and Yakutat Bay, finding them all 



