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                                                                    EXHIBIT 24.1

                               POWER OF ATTORNEY

     KNOWN ALL PERSONS BY THESE PRESENTS, that each of F.N.B. Corporation, and
the several undersigned Officers and Directors thereof whose signatures appear
below, hereby makes, constitutes and appoints John D. Waters, its, his and her
true and lawful attorney with power to act without any other and with full power
of substitution, to execute, deliver and file in its, his and her name and on
its, his and her behalf, and in each of the undersigned Officer's Director's
capacity or capacities as shown below, (a) a Registration Statement of F.N.B.
Corporation on Form S-4 (or other appropriate form) with respect to the
registration under the Securities Act of 1933, as amended, of up to 1,252,000
shares of common stock, par value $2.00 per share, of F.N.B. Corporation, to be
issued in exchange for shares of common stock of Guaranty Bank & Trust Company,
Venice, Florida, upon consummation of the proposed merger of Guaranty Bank &
Trust Company with and into Southwest Bank Interim No. 4, National Association,
a national chartered interim bank wholly-owned by F.N.B. Corporation, and any
and all documents in support thereof or supplements thereto and any and all
amendments, including any and all post-effective amendments, to the foregoing
(hereinafter called the "Registration Statement"), and (b) such registration
statements, petitions, applications, consents to service of process or other
instruments, any and all documents in support thereof or supplemental thereto,
and any and all documents in support thereof or supplemental thereto, and any
and all amendments or supplements to the foregoing, as may be necessary or
advisable to qualify or register the securities covered by said Registration
Statement under such securities laws, regulations or requirements as may be
applicable; and each of F.N.B. Corporation and said Officers and Directors
hereby grants to said attorney full power and authority to do and perform each
and every act and thing whatsoever as said attorney may deem necessary or
advisable to carry out fully the intent of this power of attorney to the same
extent and with the same effect as F.N.B. Corporation might or could do, and as
each of said Officers and Directors might or could do personally in his or her
capacity or capacities as aforesaid, and each of F.N.B. Corporation and said
Officers and Directors hereby ratifies and confirms all acts and things which
said attorney might do or cause to be done by virtue of this power of attorney
and its, his or her signature as the same may be signed by said attorney, or any
of them, to any or all of the following (and/or any and all amendments and
supplements to any or all thereof): such Registration Statement under the
Securities Act of 1933, as amended, and all such registration statements,
petitions, applications, consents to service of process and other instruments,
and any and all documents in support thereof or supplemental thereto, under such
securities laws, regulations and requirements as may be applicable. 
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     IN WITNESS WHEREOF, F.N.B. Corporation has caused this power of attorney 
to be signed on its behalf, and each of the undersigned Officers and Directors 
in the capacity or capacities noted has hereunto set his or her hand as of the 
date indicated below. This Power of Attorney may be executed in counterparts 
which, when taken together, constitute a single original hereof.



                               F.N.B. CORPORATION
                                  (Registrant)


                               By: /s/ Peter Mortensen
                                   ------------------------
                                   Peter Mortensen
                                   Chairman and President
                          
                          
                               Dated:  November 9, 1998
                                      ---------------------

                                                             
/s/ Peter Mortensen  
- ------------------------   Chairman of the Board                  Date: November 9, 1998
Peter Mortensen            President and Chief Executive Officer        ----------------
                           (Principal Executive Officer)
/s/ Stephen J. Gurgovits
- ------------------------   Executive Vice President               Date: November 9, 1998
Stephen J. Gurgovits       and Director                                 ----------------

/s/ William J. Rundorff
- ------------------------   Executive Vice President               Date: November 9, 1998
William J. Rundorff                                                     ----------------

/s/ John D. Waters
- ------------------------   Vice President and Chief               Date: November 9, 1998
John D. Waters             Finance Officer (Principal                   ----------------
                           Financial and Accounting Officer)
/s/ W. Richard Blackwood
- ------------------------   Director                               Date: November 9, 1998
W. Richard Blackwood                                                    ----------------

                    
- ------------------------   Director                               Date:               
William B. Campbell                                                     ----------------

/s/ Charles T. Cricks
- ------------------------   Director                               Date: November 9, 1998
Charles T. Cricks                                                       ----------------
                     
          
/s/ Henry M. Ekker, Esq.                                         Date: November 9, 1998   
- ------------------------   Director                                    ----------------
Henry M. Ekker, Esq.

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- ---------------------------------------     Director                            Date:______________
Thomas C. Elliott

/s/Thomas W. Hodge
- ---------------------------------------     Director                            Date: November 9, 1998
Thomas W. Hodge

/s/James S. Lindsay
- ---------------------------------------     Director                            Date: November 9, 1998
James S. Lindsay

/s/Paul P. Lynch
- ---------------------------------------     Director                            Date: November 9, 1998
Paul P. Lynch

/s/Edward J. Mace
- ---------------------------------------     Director                            Date: November 9, 1998
Edward J. Mace

/s/Robert S. Moss
- ---------------------------------------     Director                            Date: November 9, 1998
Robert S. Moss


- ---------------------------------------     Director                            Date:______________
Richard C. Myers


- ---------------------------------------     Director                            Date:______________
William A. Quinn

/s/George A. Seeds
- ---------------------------------------     Director                            Date: November 9, 1998
George A. Seeds

/s/William J. Strimbu
- ---------------------------------------     Director                            Date: November 9, 1998
William J. Strimbu


- ---------------------------------------     Director                            Date:______________
Gary L. Tice

/s/Archie O. Wallace
- ---------------------------------------     Director                            Date: November 9, 1998
Archie O. Wallace


- ---------------------------------------     Director                            Date:______________
Joseph M. Walton


- ---------------------------------------     Director                            Date:______________
James T. Weller

/s/Eric J. Werner
- ---------------------------------------     Director                            Date: November 9, 1998
Eric J. Werner, Esq.



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/s/ Robert B. Wiley
- ---------------------------------------     Director                            Date: November 9, 1998
Robert B. Wiley

- ---------------------------------------     Director                            Date:______________
Donna C. Winner