Exhibit 10.14.16
 
                 SECOND AMENDMENT TO REVOLVING CREDIT AGREEMENT
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          THIS SECOND AMENDMENT TO REVOLVING CREDIT AGREEMENT, dated as of
August 3, 1998 (this "Amendment"), by and among X.L. Insurance Company, Ltd. and
X.L. Global Reinsurance Company, Ltd. (formerly known as X.L. Reinsurance
Company, Ltd.) (the "Borrowers"), X.L. Insurance Company, Ltd. and EXEL
Acquisition Ltd. (the "Guarantors"), MELLON BANK, N.A., (the "Agent") and the
banks listed on the signature pages hereto (collectively, the "Banks").

                              W I T N E S S E T H:
                              ------------------- 

          WHEREAS, the Borrowers, the Guarantors, the Banks, and the Agent are
parties to a Revolving Credit Agreement, dated as of June 6, 1997, (as amended
by the First Amendment thereto, dated as of November 5, 1997, the "Credit
Agreement"), pursuant to which the Banks have agreed, on the terms and subject
to the conditions described therein, to make Loans to the Borrowers; and

          WHEREAS, the Borrowers have requested the Banks to make certain
changes to the Credit Agreement; and

          WHEREAS, the Banks are willing to amend the Credit Agreement as set
forth below; and

          WHEREAS, capitalized terms used herein and not otherwise defined shall
have the meanings assigned to them in the Credit Agreement;

          NOW THEREFORE, in consideration of the premises and of the mutual
covenants herein contained, and intending to be legally bound hereby, the
parties hereto agree as follows:

          SECTION 1.  AMENDMENTS TO CREDIT AGREEMENT.  The Credit Agreement is
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hereby amended as follows:

          (a) Section 1.01 of the Credit Agreement is hereby amended by adding
thereto, between the definitions of the terms "Material Adverse Effect" and
"Notes", respectively, appearing therein, the following definitions:

                    "1998 Merger" shall mean consummation of the transactions
                  provided for in the Agreement and Schemes of Arrangement among
                  EXEL Limited, EXEL Merger Company, Ltd. and Mid Ocean Limited,
                  as described in the Current Report on Form 8-K of EXEL Limited
                  dated as of March 16, 1998, as modified by the amendment and
                  restatement thereof dated April 28, 1998.

                    "1998 Reinsurance Merger Transaction" shall mean the
                  transfer, after or contemporaneously 

 
                  with consummation of the 1998 Merger, to Mid Ocean Limited by
                  X.L. Insurance of all of the common stock of X. L. Reinsurance
                  and the subsequent amalgamation of X.L. Reinsurance with Mid
                  Ocean Reinsurance Company, Ltd., the resulting corporation of
                  which amalgamation will be a Bermuda corporation which shall
                  have assumed and shall be liable for all of the obligations of
                  X.L. Reinsurance under the Loan Documents.

     (b) The definition of the term "Business Day" appearing in Section 1.01 of
the Credit Agreement is hereby amended by inserting therein, between the word
"Pennsylvania" and the period at the end thereof, the words "or Bermuda".

     (c) The definition of the term "Change of Control" appearing in Section
1.01 of the Credit Agreement is hereby amended by adding thereto, after the word
"shareholders" and before the period at the end thereof, the following phrase:
"; provided, that consummation of the 1998 Merger shall be deemed not to be a
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Change of Control".

     (d) The definition of the term "EXEL Limited" appearing in Section 1.01 of
the Credit Agreement is hereby amended to read as follows:

                    "EXEL Limited" shall mean (i) until consummation of the 1998
                  Merger, EXEL Limited, a corporation organized under the laws
                  of the Cayman Islands, British West Indies which, on the date
                  of this Agreement, is the sole shareholder of X.L. Insurance
                  Company, Ltd., except for a nominal number of shares owned by
                  two nominee shareholders required by the Bermuda Companies Law
                  and (ii) from and after consummation of the 1998 Merger, EXEL
                  Limited, a corporation organized under the laws of the Cayman
                  Islands, British West Indies which is referred to as "New
                  EXEL" in the 8-K Report referred to in the definition of 1998
                  Merger below.

     (e) The definition of the term "Indebtedness" appearing in Section 1.01 of
the Credit Agreement is hereby amended by inserting therein, between the phrase
"of a Person shall mean" and the colon, the following:

                  (it being understood, for the avoidance of doubt, that
                  insurance payment liabilities, as such, and liabilities
                  arising in the ordinary course of such Person's business as an
                  insurance company or corporate member of Lloyds (other than in
                  connection with the financing activities of such Person or of
                  any 

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                  of such Person's Affiliates) shall not be deemed to constitute
                  Indebtedness)

     (f) The definition of the term "X.L. Reinsurance" appearing in Section 1.01
of the Credit Agreement is hereby amended to read as follows:

                    "X.L. Reinsurance" shall mean (i) until consummation of the
                  1998 Reinsurance Merger Transactions, X.L. Global Reinsurance
                  Company, Ltd., a corporation organized under the laws of
                  Bermuda, and (ii) from and after consummation of the 1998
                  Reinsurance Merger Transaction, X.L. Mid Ocean Reinsurance
                  Company, Ltd., a corporation organized under the laws of
                  Bermuda and the resulting corporation of the amalgamation
                  referred to in the definition of the term "1998 Reinsurance
                  Merger Transaction" appearing in this Section.


     (g) Section 5.08 of the Credit Agreement is hereby amended by adding
thereto a new second sentence, to read as follows:

                  "General corporate purposes", as used in the immediately
                  preceding sentence with respect to the use of proceeds of
                  Loan, may include payment of dividends.

     (h) The introductory phrase of Article VI of the Credit Agreement,
appearing before Section 6.01, is hereby amended to read as follows:

                  Each Borrower covenants to the Agent and to each Bank as
                  follows (it being understood that nothing in Section 6.01,
                  Section 6.02 or Section 6.04 hereof shall prohibit the
                  consummation of the 1998 Reinsurance Merger Transaction):

     (i) Section 7.01(h) of the Credit Agreement is hereby amended to read as
follows:

                  (h) EXEL Limited shall cease to own, beneficially and of
                  record, directly or indirectly all of the outstanding voting
                  shares of common stock of X.L. Reinsurance, except for a
                  nominal number of shares owned by nominee shareholders
                  required by the Bermuda Companies Law.

     (j) Section 6.03 of the Credit Agreement is hereby amended by deleting the
period at the end of paragraph (f) 

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thereof and replacing it with "; or" and by adding after such paragraph (f) a
new paragraph (g) to read as follows:

                  (g) Liens securing letter of credit reimbursement obligations
                  under the Security Agreement listed on Schedule 6.03(g) hereto
                  (and extension, renewal and replacement Liens upon the same
                  property or upon substitute property of approximately the same
                  value, provided the total amount secured by each Lien
                  constituting such extension, renewal or replacement Liens
                  shall not exceed the maximum amount secured by the Liens
                  theretofore existing).


    (k) Section 6.08(d) of the Credit Agreement is hereby amended by adding
thereto, between the phrase "Schedule 6.08(d)" and the semicolon at the end
thereof, the phrase "and Indebtedness described on Schedule 6.03(g) hereto".

    
    (l) The Credit Agreement is hereby amended by adding thereto a Schedule
6.03(g) in the form attached to this Amendment as Schedule 6.03(g).

     SECTION 2.  EFFECT OF AMENDMENT.  The Credit Agreement, as amended by this
                 -------------------                                      
Amendment, is in all respects ratified, approved and confirmed and shall, as so
amended, remain in full force and effect.

     SECTION 3.  GOVERNING LAW.  This Amendment shall be deemed to be a contract
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under the laws of the Commonwealth of Pennsylvania and for all purposes shall be
governed by and construed and enforced in accordance with the laws of said
Commonwealth.

     SECTION 4.  COUNTERPARTS.  This Amendment may be executed in any number
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of counterparts and by the different parties hereto on separate counterparts,
each of which, when so executed, shall be deemed an original, but all such
counterparts shall constitute but one and the same instrument.

     IN WITNESS WHEREOF, the parties hereto have executed this Amendment as of
the date first above written.

                                             X.L. INSURANCE COMPANY, LTD.
                                             as a Borrower and as a Guarantor


                                             By:______________________________
                                             Title:___________________________

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                              X.L. GLOBAL REINSURANCE COMPANY, LTD. (formerly
                                X.L. Reinsurance Company, Ltd.),
                                as a Borrower


                              By:___________________________________
                              Title:________________________________ 


                              EXEL ACQUISITION LTD.,
                                as a Guarantor


                              By:___________________________________
                              Title:________________________________ 


                              MELLON BANK, N.A., as a Bank
                                and as Agent


                              By:___________________________________
                              Title:________________________________ 


                              BANK OF TOKYO - MITSUBISHI LTD.,
                                as a Bank

                              By:___________________________________
                              Title:________________________________ 


                              DEUTSCHE BANK AG, NEW YORK OR CAYMAN ISLANDS
                                BRANCHES,
                                as a Bank


                              By:___________________________________
                              Title:________________________________ 

                              By:___________________________________
                              Title:________________________________ 


                              THE BANK OF NOVA SCOTIA,
                                as a Bank


                              By:___________________________________
                              Title:________________________________ 

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                              THE CHASE MANHATTAN BANK,
                                  as a Bank


                              By:___________________________________
                              Title:________________________________ 


                              THE BANK OF BERMUDA LIMITED,
                                  as a Bank


                              By:___________________________________
                              Title:________________________________ 


                              ROYAL BANK OF CANADA,
                                  as a Bank


                              By:___________________________________
                              Title:________________________________ 


                              BANQUE NATIONALE DE PARIS,
                                  as a Bank


                              By:___________________________________
                              Title:________________________________ 


                              By:___________________________________
                              Title:________________________________ 


                              BANK OF AMERICA NT&SA,
                                  as a Bank


                              By:___________________________________
                              Title:________________________________ 


                              CREDIT LYONNAIS NEW YORK BRANCH,
                                  as a Bank

                              By:___________________________________
                              Title:________________________________ 

                              By:___________________________________
                              Title:________________________________ 

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                              BANK AUSTRIA AKTIENGESELLSCHAFT,
                                  as a Bank


                              By:___________________________________
                              Title:________________________________ 


                              By:___________________________________
                              Title:________________________________ 

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                               Schedule 6.03(g)


          From and after consummation of the 1998 Reinsurance Merger
Transaction, the Lien referred to in Section 6.03(g) of the Credit Agreement
with reference to this Schedule is a Lien on investment securities and similar
property in favor of Citibank, N.A., as agent or as issuing bank, securing
reimbursement obligations and related obligations with respect to letters of
credit issued for the account of X. L. Reinsurance or its affiliates (or for the
account of its predecessor, Mid Ocean Reinsurance Company, Ltd. or its
affiliates) in an aggregate face amount not exceeding $325,000,000. The
Indebtedness described in Section 6.08(d) of the Credit Agreement with reference
to this Schedule consists of the obligations referred to in the immediately
preceding sentence.

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