Miscellaneous Subsurface Methods 



675 



in the field of view of the camera. To orient the apparatus when it is sup- 

 ported by a cable is somewhat more difficult. Even with a slight deviation 

 of the axis of the bore hole from the vertical there is a strong tendency for 

 the camera to twist around so that it consistently faces the low side of 

 the hole with the "push-over" springs facing the high side. Pictures taken 

 in the same well on different trips usually show the same views because of 

 this tendency of the camera to orient itself. Many schemes have been 

 suggested for taking pictures in all radial directions in the bore hole. One 



m'lmm' 



)Sl^ 



Figure 363. Pay-zone section of -well. Also shown are some very large openings to- 

 gether with well-developed smaller openings, most of which are confined to lower 

 one-third of picture. Perhaps some of this porosity may have been formed by 

 leaching out of remains of organisms such as corals. Some of the apparent dis- 

 tortion around large openings may have been caused by growth of reef structure 

 (2,719 feet) . 



that looks promising is that for using a cylindrical or bowl-shaped picture 

 window extending completely around the circumference of the water 

 chamber, omitting the mirror, and using a very wide-angle camera lens. 

 Another method would be to substitute for the plane mirror a cone- 

 shaped mirror or a submarine-periscope-type mirror with its axis vertical. 

 The distortion produced by such a mirror could be cancelled out by using 



