<ARTICLE>                     5
<MULTIPLIER>                  1000

                                                             
<PERIOD-TYPE>                                                   6-MOS
<FISCAL-YEAR-END>                                               DEC-31-1999
<PERIOD-END>                                                    JUN-30-1999
<CASH>                                                               13,379
<SECURITIES>                                                         50,557
<RECEIVABLES>                                                        63,378
<ALLOWANCES>                                                          1,946
<INVENTORY>                                                          55,953
<CURRENT-ASSETS>                                                    191,623
<PP&E>                                                              251,878
<DEPRECIATION>                                                      165,342
<TOTAL-ASSETS>                                                      361,582
<CURRENT-LIABILITIES>                                                67,271
<BONDS>                                                              20,162
<PREFERRED-MANDATORY>                                                     0
<PREFERRED>                                                               0
<COMMON>                                                             15,000
<OTHER-SE>                                                          224,218
<TOTAL-LIABILITY-AND-EQUITY>                                        361,582
<SALES>                                                             140,545
<TOTAL-REVENUES>                                                    146,813
<CGS>                                                                90,847
<TOTAL-COSTS>                                                       119,850
<OTHER-EXPENSES>                                                        337
<LOSS-PROVISION>                                                          0
<INTEREST-EXPENSE>                                                      630
<INCOME-PRETAX>                                                      25,996
<INCOME-TAX>                                                          9,735
<INCOME-CONTINUING>                                                  16,261
<DISCONTINUED>                                                            0
<EXTRAORDINARY>                                                           0
<CHANGES>                                                                 0
<NET-INCOME>                                                         16,261
<EPS-BASIC>                                                          1.60
<EPS-DILUTED>                                                          1.57