from to 4,000 psi and 70 to 35°F, respectively. This portion of the 

 cycle represented the dive of the vehicle. Upon completing the desired 

 loading time of 500 hours, the pressure and temperature were simultaneously 

 changed from 4,000 to psi and 35 to 70°F, respectively. 



The displacements at the center of the low-pressure face were taken 

 twice a day except for weekends and holidays. The morning and the after- 

 noon were chosen for the displacement recordings because the minimum and 

 maximum pressures for each working day corresponded with the minimum 

 and maximum temperature fluctuations for the 24 hours of the day. 



46 



