Long 12.75-inch diameter steel pipe pins inserted 

 into the four corner legs were driven 63 feet into the 

 sea floor at an angle of 5 degrees from the vertical. 

 The tops of the pins were then welded to the legs, 

 thus securely anchoring the framework to the sea 

 floor. 



The instrument house with its cement deck was 

 lowered onto anchor pins and framework. I-beam 

 house supports were welded to top of anchor pins. 

 Supports for the catwalk were also welded into place. 

 Finally, ladders, catwalks, and the instruments were 

 added. After 2 years' operation, this original instru- 

 ment house proved too small, and was enlarged by 

 cantilevering to the north and south. 



FINAL ATTACHMENT 1 * ^^ 



111 



