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                                                                      EXHIBIT 24
 
                               POWER OF ATTORNEY
 
     We, the undersigned hereby constitute Charles W. Cramb and John M. Coleman,
or either of them, our true and lawful attorneys with full power to sign for us
in our name and in the capacity indicated below the Annual Report on Form 10-K
pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934, filed
for the Company with the Securities and Exchange Commission for the year ended
December 31, 1997, and any and all amendments and supplements thereto, hereby
ratifying and confirming our signatures as they may be signed by our said
attorneys, or either of them, to said Report and to any and all amendments and
supplements to said Report.
 
     WITNESS Our Hand and Seal on the Date set forth below.
 
<TABLE>
<CAPTION>
                     SIGNATURES                                        TITLE                       DATE
                     ----------                                        -----                       ----
<S>                                                    <C>                                    <C>
 
                   ALFRED M. ZEIEN                             Chairman of the Board          March 19, 1998
-----------------------------------------------------  of Directors, Chief Executive Officer
                   Alfred M. Zeien                                 and Director
 
                  MICHAEL C. HAWLEY                     President, Chief Operating Officer    March 19, 1998
-----------------------------------------------------              and Director
                  Michael C. Hawley
 
                 JOSEPH E. MULLANEY                      Vice Chairman of the Board, Chief    March 19, 1998
-----------------------------------------------------       Legal Officer and Director
                 Joseph E. Mullaney
 
                  CHARLES W. CRAMB                         Senior Vice President, Chief       March 19, 1998
-----------------------------------------------------          Financial Officer and
                  Charles W. Cramb                         Principal Accounting Officer
 
                  WARREN E. BUFFETT                                  Director                 March 19, 1998
-----------------------------------------------------
                  Warren E. Buffett
 
                   WILBUR H. GANTZ                                   Director                 March 19, 1998
-----------------------------------------------------
                   Wilbur H. Gantz
 
                 MICHAEL B. GIFFORD                                  Director                 March 19, 1998
-----------------------------------------------------
                 Michael B. Gifford
 
                  CAROL R. GOLDBERG                                  Director                 March 19, 1998
-----------------------------------------------------
                  Carol R. Goldberg
 
                  HERBERT H. JACOBI                                  Director                 March 19, 1998
-----------------------------------------------------
                  Herbert H. Jacobi
 
                   HENRY R. KRAVIS                                   Director                 March 19, 1998
-----------------------------------------------------
                   Henry R. Kravis
 
                RICHARD R. PIVIROTTO                                 Director                 March 19, 1998
-----------------------------------------------------
                Richard R. Pivirotto
 
                    JUAN M. STETA                                    Director                 March 19, 1998
-----------------------------------------------------
                    Juan M. Steta
 
               ALEXANDER B. TROWBRIDGE                               Director                 March 19, 1998
-----------------------------------------------------
               Alexander B. Trowbridge
</TABLE>
 
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