<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY INFORMATION EXTRACTED FROM THE CONSOLIDATED
BALANCE SHEET AND CONSOLIDATED STATEMENT OF INCOME FILED AS PART OF THE 
QUARTERLY REPORT ON FORM 10-Q AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE
TO SUCH QUARTERLY REPORT ON FORM 10-Q.
</LEGEND>
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               SEP-30-1997
<CASH>                                         $10,339
<SECURITIES>                                        $0
<RECEIVABLES>                                 $151,967
<ALLOWANCES>                                    $1,510
<INVENTORY>                                    $95,372
<CURRENT-ASSETS>                              $273,416
<PP&E>                                      $1,180,169
<DEPRECIATION>                                $682,270
<TOTAL-ASSETS>                                $864,116
<CURRENT-LIABILITIES>                         $125,119
<BONDS>                                             $0
<PREFERRED-MANDATORY>                               $0
<PREFERRED>                                         $0
<COMMON>                                          $554
<OTHER-SE>                                    $539,420
<TOTAL-LIABILITY-AND-EQUITY>                  $864,116
<SALES>                                       $613,180
<TOTAL-REVENUES>                              $613,180
<CGS>                                         $416,089
<TOTAL-COSTS>                                 $521,077
<OTHER-EXPENSES>                                    $0
<LOSS-PROVISION>                                    $0
<INTEREST-EXPENSE>                                $559
<INCOME-PRETAX>                                $92,383
<INCOME-TAX>                                   $33,295
<INCOME-CONTINUING>                            $59,088
<DISCONTINUED>                                      $0
<EXTRAORDINARY>                                     $0
<CHANGES>                                           $0
<NET-INCOME>                                   $59,088
<EPS-PRIMARY>                                    $1.06
<EPS-DILUTED>                                    $1.06