MAJOR PROGRAM AREAS 21 



froth in the pipe. The reduction in density in the upper portion of the pipe causes water- 

 sediment flow into the bottom. This flow has such velocity that solids are raised to the sur- 

 face, where they are discharged into recovery barrels. 



The rotary coring method involves a coring assembly mounted in a frame with tripod legs. 

 The device sits on the ocean floor and is intended to drill a six-foot-long core of sand, gravel, 

 nodular material, or rock. The unit is lowered and raised from a surface vessel, from which 

 power is supplied to a motor mounted on the device. 



Tests of both units indicated promise, but there is still work to do before either become 

 operational. With the airlift method, handling is quite difficult because of the long lengths 

 (over 200 ft) of large-diameter pipe used. The coring-device unit tipped over each time it 

 was placed on the sea floor, indicating a need for adjusting the unit to the topography of the 

 area. 



PORPOISE UTILIZATION 



Sealab II provided an opportunity to test the feasibility of using porpoises in conjunction 

 with the man-in-the-sea program (Chapter 45). It was planned that Sealab II aquanauts would 

 be tethered at all times while swimming at ranges beyond the visual ranges of the habitat. 

 However, should a failure occur and the diver become disoriented, a strong possibility exists 

 that he would be unable to find his way back to his ocean-floor habitat. Therefore, the avail- 

 ability of a trained porpoise to perform certain vital work functions, in particular guiding a 

 lost diver back to the habitat, and also carrying equipment and messages to divers working 

 some distance from the habitat, would be of great importance. 



It was planned that the porpoise would be summoned from the surface by buzzer to an 

 aquanaut at Sealab. That individual would snap a line to one of the rings on the animal's har- 

 ness, then turn off his buzzer. The "lost" aquanaut would then summon the porpoise by turn- 

 ing on his buzzer. After unsnapping the line that the animal had carried to him, he would have 

 a guide back to Sealab (Figs. 15, 16). 



This procedure, using during Sealab, indicated that a porpoise can be trained to perform 

 useful and even vital tasks in programs such as Sealab. It can adapt relatively quickly to a 

 strange and in many ways disturbing environment, and, once trained, will perform with a high 

 degree of precision and reliability. 



An unexpected opportunity developed during this study to observe another seagoing mammal, 

 a sea lion that wanderedinto the Sealab area (Figs. 17, 18). The sea lion was trained to respond 

 to an underwater buzzer and was observed feeding on the fish that gathered around Sealab. On 

 several occasions the sea lion swam into the Sealab entry trunk, breathed the atmosphere, and 

 returned to the surface with no ill effects. 



DIETETICS 



In the past, too little importance has been placed on food and food preparation as it may 

 affect morale. If man is to be subjected to other than ideal conditions, i.e., living and working 

 on the ocean floor for prolonged periods of time, his motivation must not be stinted by being 

 underfed. 



In preparation of the menu (Chapter 46), it was necessary to keep in mind the following 

 considerations: 



1. All foods must be easily prepared. 



2. Packaging must be compatible with the extreme pressure conditions (at least 110 psia). 



3. Most food would be prepared and eaten on an individual basis, rather than as a group 

 of ten men. 



