<ARTICLE> 5
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-START>                             JAN-01-1997
<PERIOD-END>                               SEP-30-1997
<CASH>                                           4,905
<SECURITIES>                                   163,068
<RECEIVABLES>                                   42,312
<ALLOWANCES>                                     1,374
<INVENTORY>                                     14,410
<CURRENT-ASSETS>                                75,653
<PP&E>                                         239,707
<DEPRECIATION>                                  98,632
<TOTAL-ASSETS>                                 443,368
<CURRENT-LIABILITIES>                           37,471
<BONDS>                                         59,914
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                        10,669
<OTHER-SE>                                     228,654
<TOTAL-LIABILITY-AND-EQUITY>                   443,368
<SALES>                                        188,922
<TOTAL-REVENUES>                               191,695
<CGS>                                          122,483
<TOTAL-COSTS>                                  122,483
<OTHER-EXPENSES>                                39,505
<LOSS-PROVISION>                                   791
<INTEREST-EXPENSE>                               4,147
<INCOME-PRETAX>                                 24,769
<INCOME-TAX>                                     8,454
<INCOME-CONTINUING>                             16,315
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                    16,315
<EPS-PRIMARY>                                     3.80
<EPS-DILUTED>                                        0