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                                                                      EXHIBIT 11


                               WESTERN ATLAS INC.

                 STATEMENT OF COMPUTATION OF EARNINGS PER SHARE
                      (in thousands, except per share data)

<TABLE>
<CAPTION>
                                                                                                          FIVE MONTHS               
                                                                  YEAR ENDED DECEMBER 31,                    ENDED        YEAR ENDED
                                                  ----------------------------------------------------     DECEMBER 31,     JULY 31,
                                                     1997           1996          1995          1994          1993           1993   
                                                  ---------      ---------     ---------     ---------     ---------      --------- 
<S>                                               <C>            <C>           <C>           <C>           <C>            <C>       
BASIC EARNINGS PER SHARE:                                                                                                           
Earnings (loss) from continuing operations        $  91,811      $  69,922     $  61,409     $  39,748     $(190,580)     $  40,791 
Earnings (loss) from discontinued operations       (154,927)        55,743        38,430        37,993         7,303         33,129 
                                                  ---------      ---------     ---------     ---------     ---------      --------- 
Earnings (loss) before cumulative effect of a                                                                                       
  change in accounting principle                    (63,116)       125,665        99,839        77,741      (183,277)        73,920 
Cumulative effect of a change in accounting                                                                                         
  principle (a)                                          --             --            --            --            --         (1,119)
                                                  ---------      ---------     ---------     ---------     ---------      --------- 
Net earnings available for common shares          $ (63,116)     $ 125,665     $  99,839     $  77,741     $(183,277)     $  72,801 
                                                  =========      =========     =========     =========     =========      ========= 
                                                                                                                                    
Earnings (loss) per share from continuing                                                                                           
  operations                                      $    1.69      $    1.31     $    1.16     $     .83     $   (4.18)     $     .87 
Earnings (loss) per share from discontinued                                                                                         
  operations                                          (2.85)          1.04           .72           .80           .16            .70 
                                                  ---------      ---------     ---------     ---------     ---------      --------- 
Earnings (loss) per share before cumulative                                                                                         
  effect of a change in accounting principle          (1.16)          2.35          1.88          1.63         (4.02)          1.57 
Cumulative effect of a change in accounting                                                                                         
  principle (a)                                          --             --            --            --            --           (.02)
                                                  ---------      ---------     ---------     ---------     ---------      --------- 
Total                                             $   (1.16)     $    2.35     $    1.88     $    1.63     $   (4.02)     $    1.55 
                                                  =========      =========     =========     =========     =========      ========= 
                                                                                                                                    
SHARES USED IN COMPUTATION:                                                                                                         
Weighted-average common shares outstanding                                                                                          
  (net of treasury shares)                           54,252         53,490        53,074        47,662        45,582         46,999 
                                                  =========      =========     =========     =========     =========      ========= 
                                                                                                                                    
DILUTED EARNINGS PER SHARE:                                                                                                         
Earnings (loss) from continuing operations        $  91,811      $  69,922     $  61,409     $  39,748     $(190,580)     $  40,791 
Earnings (loss) from discontinued operations       (154,927)        55,743        38,430        37,993         7,303         33,129 
                                                  ---------      ---------     ---------     ---------     ---------      --------- 
Earnings (loss) before cumulative effect of a                                                                                       
  change in accounting principle                    (63,116)       125,665        99,839        77,741      (183,277)        73,920 
Cumulative effect of a change in accounting                                                                                         
  principle (a)                                          --             --            --            --            --         (1,119)
                                                  ---------      ---------     ---------     ---------     ---------      --------- 
Net earnings available for common shares and                                                                                        
  common stock equivalent shares deemed                                                                                             
  to have a dilutive effect                       $ (63,116)     $ 125,665     $  99,839     $  77,741     $(183,277)     $  72,801 
                                                  =========      =========     =========     =========     =========      ========= 
Earnings (loss) per share from continuing 
  operations                                      $    1.65      $    1.29     $    1.14     $     .82     $   (4.18)     $     .87 
Earnings (loss) per share from discontinued                                                                                         
  operations                                          (2.78)          1.03           .72           .78           .16            .70 
                                                  ---------      ---------     ---------     ---------     ---------      --------- 
Earnings (loss) per share before cumulative                                                                                        
  effect of a change in accounting principle          (1.13)          2.32          1.86          1.60         (4.02)          1.57 
Cumulative effect of a change in accounting                                                                                        
  principle (a)                                          --             --            --            --            --           (.02)
                                                  ---------      ---------     ---------     ---------     ---------      --------- 
Total                                             $   (1.13)     $    2.32     $    1.86     $    1.60     $   (4.02)     $    1.55 
                                                  =========      =========     =========     =========     =========      ========= 
                                                                                                                                    
SHARES USED IN COMPUTATION:                                                                                                         
Weighted average common shares outstanding                                                                                          
  (net of treasury shares)                           54,252         53,490        53,074        47,662        45,582         46,999 
Additional potentially dilutive securities                                                                                          
  (equivalent in common stock)                        1,361            781           681           857            --             -- 
                                                  ---------      ---------     ---------     ---------     ---------      --------- 
Total                                                55,613         54,271        53,755        48,519        45,582         46,999 
                                                  =========      =========     =========     =========     =========      ========= 
</TABLE>                                        
                                                
                                                
(a)  Amounts pertain to continuing operations.  
                                                
                                                
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