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                                                                     EXHIBIT 4.2

      THIS FIRST SUPPLEMENTAL INDENTURE, dated as of October 15, 1993, is
between CNA FINANCIAL CORPORATION, a Delaware corporation (the "Company"), and
THE FIRST NATIONAL BANK OF CHICAGO, a national banking association, as trustee
(herein called the "Trustee").

                              PRELIMINARY STATEMENT

      The Company and the Trustee have entered into an Indenture (herein called
the "Indenture"), dated as of March 1, 1991. Capitalized terms used herein, not
otherwise defined herein, shall have the meanings given them in the Indenture.

      Section 8.1 of the Indenture provides that, under certain circumstances, a
supplemental indenture may be entered into by the Company and the Trustee
without the consent of any Holders of Securities. In accordance with the terms
of Section 8.1(d) of the Indenture, the Company has, by Board Resolution,
authorized this First Supplemental Indenture. The Trustee has determined that
this First Supplemental Indenture is in form satisfactory to it.

      All things necessary to make this First Supplemental Indenture a valid
agreement of the Company and the Trustee and a valid amendment of and supplement
to the Indenture have been done.

      NOW, THEREFORE, THIS FIRST SUPPLEMENTAL INDENTURE WITNESSETH:

      For and in consideration of the premises, it is mutually covenanted and
agreed, for the equal and proportionate benefit of all Holders of the Securities
issued under the Indenture from and after the date of this First Supplemental
Indenture, as follows:

      1. Article One will be modified by the addition of the following
definitions:

      "Depository" means, unless otherwise specified by the Company pursuant to
Section 2.3, with respect to Securities of any series issuable or issued as a
Global Security, The Depository Trust Company, New York, New York, or any
successor thereto registered as a clearing agency pursuant to the provisions of
Section 17A of the Securities Exchange Act of 1934, as amended, or other
applicable statute or regulation.

      "Global Security", when used with respect to any series of Securities
issued hereunder, means a Security which is executed by the Company and
authenticated and delivered by the Trustee to the Depository pursuant to the
Depository's instruction, all in accordance with this Indenture and an indenture
supplemental hereto, if any, or Board Resolution and pursuant to a Company
Order, which Global Security shall be registered in the name of the Depository
or its nominee and which shall represent, and shall be denominated in an amount
equal to the aggregate principal amount of, all of the Outstanding Securities of
such series or any portion thereof, in either case having the same terms,
including, without limitation, the same original issue date, date or dates on
which principal is due, and interest rate or method of determining interest.

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      2. Article One will be modified by replacing the phrase "Financial Vice
President" in the definitions of "Company Order" and "Officer's Certificate"
with the phrase "Senior Vice President and Chief Financial Officer".

      3. Article One will be amended by adding the phrase "or other committee"
after "Executive Committee" in the definition of "Board of Directors".

      4. Article Two, Section 2.3(3) will be modified by replacing the phrase
"authorized from" with the phrase "authorized form".

      5. Article Two will be modified by the addition of a new Section 2.14 as
follows:

      Section 2.14. Securities Issuable in the Form of a Global Security. (a) If
the Company shall establish pursuant to Sections 2.1 and 2.3 that the Securities
of a particular series are to be issued in whole or in part in the form of one
or more Global Securities, then the Company shall execute and the Trustee or its
agent shall, in accordance with Section 2.4 and the Company Order delivered to
the Trustee or its agent thereunder, authenticate and deliver such Global
Security or Global Securities, which (i) shall represent, and shall be
denominated in an amount equal to the aggregate principal amount of, the
Outstanding Securities of such series to be represented by such Global Security
or Global Securities, or such portion thereof as the Company shall specify in a
Company Order, (ii) shall be registered in the name of the Depository for such
Global Security or Global Securities or its nominee, (iii) shall be delivered by
the Trustee or its agent to the Depository or pursuant to the Depository's
instruction and (iv) shall bear a legend substantially to the following effect:
"Unless this certificate is presented by an authorized representative of the
Depository to the Company or its agent for registration of transfer, exchange,
or payment, and any certificate issued is registered in the name of the nominee
of the Depository or in such other name as is requested by an authorized
representative of the Depository (and any payment is made to the nominee of the
Depository or to such other entity as is requested by an authorized
representative of the Depository), ANY TRANSFER, PLEDGE, OR OTHER USE HEREOF FOR
VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered
owner hereof, the nominee of the Depository, has an interest herein."

      (b) Notwithstanding any other provision of this Section 2.14 or of Section
2.8, and subject to the provisions of paragraph (c) below, unless the terms of a
Global Security expressly permit such Global Security to be exchanged in whole
or in part for individual certificates representing Securities, a Global
Security may be transferred, in whole but not in part and in the manner provided
in Section 2.8, only to a nominee of the Depository for such Global Security, or
to the Depository, or a successor Depository for such Global Security selected
or approved by the Company, or to a nominee of such successor Depository.

      (c) (i) If at any time the Depository for a Global Security notifies the
Company that it is unwilling or unable to continue as Depository for such Global
Security or if at any time the Depository for the Global Securities for such
series shall no longer be eligible or in good standing under the Securities
Exchange Act of 1934, as amended, or other applicable statute or regulation, the
Company shall appoint a successor Depository with respect to such Global
Security. If a successor Depository for such Global Security is not appointed by
the Company

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within 90 days after the Company receives notice or becomes aware of such
ineligibility, the Company will execute, and the Trustee or its agent, upon
receipt of a Company Request for the authentication and delivery of certificates
representing Securities of such series in exchange for such Global Security,
will authenticate and deliver, certificates representing Securities of such
series of like tenor and terms in an aggregate principal amount equal to the
principal amount of the Global Security in exchange for such Global Security.

      (ii) The Company may at any time and in its sole discretion determine that
the Securities of any series or portion thereof issued or issuable in the form
of one or more Global Securities shall no longer be represented by such Global
Security or Global Securities. In such event the Company will execute, and the
Trustee, upon receipt of a Company Request for the authentication and delivery
of certificates representing Securities of such series in exchange in whole or
in part for such Global Security, will authenticate and deliver certificates
representing Securities of such series of like tenor and terms in definitive
form in an aggregate principal amount equal to the principal amount of such
Global Security or Global Securities representing such series or portion thereof
in exchange for such Global Security or Global Securities.

      (iii) If specified by the Company pursuant to Sections 2.1 and 2.3 with
respect to Securities issued or issuable in the form of a Global Security, the
Depository for such Global Security may surrender such Global Security in
exchange in whole or in part for certificates representing Securities of such
series of like tenor and terms in definitive form on such terms as are
acceptable to the Company and such Depository. Thereupon the Company shall
execute, and the Trustee or its agent shall authenticate and deliver, without a
service charge, (1) to each Holder specified by the Security Registrar or the
Depository a certificate or certificates representing Securities of the same
series of like tenor and terms and of any authorized denomination as requested
by such person in an aggregate principal amount equal to and in exchange for
such Holder's beneficial interest as specified by the Security Registrar or the
Depository in the Global Security; and (2) to such Depository a new Global
Security of like tenor and terms and in an authorized denomination equal to the
difference, if any, between the principal amount of the surrendered Global
Security and the aggregate principal amount of certificates representing
Securities delivered to Holders thereof.

      (iv) In any exchange provided for in any of the preceding three
paragraphs, the Company will execute and the Trustee or its agent will
authenticate and deliver certificates representing Securities in definitive
registered form in authorized denominations for Securities of the same series or
any integral multiple thereof. Upon the exchange of the entire principal amount
of a Global Security for certificates representing Securities, such Global
Security shall be cancelled by the Trustee or its agent. Except as provided in
the preceding paragraph, certificates representing Securities issued in exchange
for a Global Security pursuant to this Section shall be registered in such names
and in such authorized denominations for Securities of that Series or any
integral multiple thereof, as the Security Registrar or Depository shall
instruct the Trustee or its agent. The Trustee or the Security Registrar shall
deliver at its Corporate Trust Office such certificates representing Securities
to the Holders in whose names such Securities are so registered.

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      6. A new paragraph will be added to the end of Section 2.8, as follows:

      None of the Trustee, any agent of the Trustee, any Paying Agent or the
Company will have any responsibility or liability for any aspect of the records
relating to or payments made on account of beneficial ownership interests of a
Global Security or for maintaining, supervising or reviewing any records
relating to such beneficial ownership interests.

      7. Article Three, Section 3.5 will be replaced with the following:

      The Company will deliver to the Trustee on or before May 1 in each year in
      which there are Securities Outstanding hereunder an Officer's Certificate,
      stating that in the course of the performance of their duties as officers
      of the Company they would normally have knowledge of any default by the
      Company in the performance or fulfillment of any covenant, agreement or
      condition contained in this Indenture, stating whether or not they have
      knowledge of any such default and, if so, specifying each such default of
      which the signers have knowledge and the nature thereof.

      8. Article Six, Section 6.2(c) will be amended by inserting at the end of
the first line the phrase "action taken by the Trustee in reasonable reliance on
an".

      9. Article Six, by replacing Section 6.2(g) with the following:

            (g) the Trustee may execute any of the trusts or powers hereunder or
      perform any duties hereunder either directly or by or through agents or
      attorneys not regularly in its employ and the Trustee shall be responsible
      for any negligent action, negligent failure to act or wilful misconduct on
      the part of any such agent or attorney.

      10. Article Eight, Section 8.2 will be amended by replacing 8.2 the phrase
"the Holder of each Security so affected" with the phrase "the Holder of the
Security so affected" and the phrase "the Holders of each Security so affected"
with the phrase "the Holder of the Security so affected".

      11. Article Ten, Section 10.2 will be amended by replacing the reference
to Section 3.11 with a reference to Section 3.8.

      12. Article Ten, Section 10.5 will be amended by replacing all references
to Section 3.11 with references to Section 3.8.

      13. Article Eleven, Section 11.4 will be amended by replacing 11.4 the
name "Thomas Igleski, Esq." with the phrase "General Counsel".

      14. This First Supplemental Indenture does not modify the Indenture in any
respect with regard to Securities issued thereunder prior to the date of this
First Supplemental Indenture, and such Securities will not be modified by this
First Supplemental Indenture.

      This instrument may be executed in any number of counterparts, each of
which so executed shall be deemed to be an original, but all such counterparts
shall together constitute but one and the same instrument.

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      IN WITNESS WHEREOF, the Company and the Trustee have caused this First
Supplemental Indenture to be duly executed by their respective officers
thereunto duly authorized and the seal of the Company and the Trustee duly
attested to be hereunto affixed all as of the day and year first above written.

                                             CNA FINANCIAL CORPORATION

[SEAL]                                       By: /s/ Patricia L. Kubera
                                                 -----------------------------
                                                   Patricia L. Kubera
                                             Its: Vice President and Controller

                                             THE FIRST NATIONAL BANK OF CHICAGO,
                                             as Trustee

[SEAL]                                       By: /s/ Steven M. Wagner
                                                 -----------------------------
                                                   Steven M. Wagner
                                             Its: Vice President

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STATE OF ILLINOIS       )
                        )  ss.:
COUNTY OF COOK          )

      On the 17th day of November, 1993, before me personally came Patricia L.
Kubera, to me known, who, being by me duly sworn, did depose and say that she
resides at Chicago, Illinois; that she is the Vice President and Controller of
CNA FINANCIAL CORPORATION, the corporation described herein and that executed
the above instrument; that she knows the seal of said corporation; that the seal
affixed to said instrument is such corporate seal; that it was so affixed by the
Board of Directors of said corporation and that she signed her name thereto by
order of the Board of Directors of said corporation.

      IN WITNESS WHEREOF, I have hereunto set my hand and affixed my official
seal the day and year in this certificate first above written.

[NOTARIAL SEAL]
                                             /s/ [Illegible]
                                             -----------------------------------
                                             Notary Public

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STATE OF ILLINOIS   )
                    ) ss.:
COUNTY OF COOK      )

      On the 17th day of November, 1993, before me personally came Steven M.
Wagner to me known, who, being by me duly sworn, did depose and say that he
resides at Chicago, Illinois; that he is a Vice President of THE FIRST NATIONAL
BANK OF CHICAGO, a national banking association, described herein and that
executed the above instrument; that he knows the seal of said corporation; that
the seal affixed to said instrument is such corporate seal; that it was so
affixed by the Board of Directors of said corporation and that he signed his
name thereto by order of the Board of Directors of said corporation.

      IN WITNESS WHEREOF, I have hereunto set my hand and affixed my official
seal the day and year in this certificate first above written.

[NOTARIAL SEAL]
                                             /s/ Somori Helmer
                                             -----------------------------------
                                             Notary Public