DIVE NO. 69 



Upon approaching the bottom, the fathometer readings 

 were questionable and, in an attempt to make a "soft land- 

 ing, " too much shot was dumped. Consequently the sea 

 floor at 22, 540 feet was sighted only briefly. The dive 

 yielded a new depth record and a test of the craft and its 

 components. 



DIVE NO. 70 



The ultimate in depths- -the Challenger Deep- -was 

 found by explosive echo- ranging to have a flat- surfaced 

 full plane approximately 0. 5 mile wide and 3 miles long. 

 The long axis of the plane was parallel to the Marianas 

 Trench axis. The geographical location of its center was 

 determined by Loran sea fixes to be 11° 18. 5 'N latitude, 

 and 142° 15. 5'E longitude. 



Upon landing, sediment was brought into suspension 

 where it remained for the duration of the 2 0- minute stay. 

 The sea floor was remarkably white and of extremely fine 

 material. It was uniformly flat and there was no evidence 

 of burrowing animals. Water current was virtually nil. 

 Microrelief was observed to be minimal. However, only 

 the area immediately adjacent to the touch-down point was 

 observed. 



Near the bottom, a jellyfish approximately 3 inches 

 in diameter was observed pulsating 6 to 8 feet from the 

 sea floor. Just prior to landing on the bottom a red shrimp 

 swam through the cone of light. 



At the bottom, Piccard reported observing a flat fish 

 looking like a sole, " Since flat fish are vertebrates and 

 teleosts, this demonstrates the capability of high forms 

 of life to exist at the greatest depths. Apparently a satis- 

 factory amount of oxygen and food replenishment exists 

 even there. 



The previous record depths for fish were about 7000 

 meters, where they have been trawled by both the Danish 

 Galathea Expedition and by the Soviets from the Vityaz. 

 It is known that certain proteins coagulate at pressures 

 considerably less than those of the deep trenches- -for 

 example, a sea urchin egg will coagulate. Hence these 

 great depths might have been entirely without higher forms 

 of life for such barochemical reasons. 



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