Exhibit 10.105


                                AMENDMENT NO. 1

                                      TO

                       INDENTURE OF FIRST NAVAL MORTGAGE

                  READING AND BATES BORNEO DRILLING CO. LTD.

                                      and

                    CHRISTIANIA BANK OG KREDITKASSE, agent

                                 as Mortgagee


                                CHARLEY GRAVES


                              Dated July 9, 1996

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             AMENDMENT NO. 1 TO INDENTURE OF FIRST NAVAL MORTGAGE


      THIS  AMENDMENT NO. 1 TO  INDENTURE OF FIRST  NAVAL MORTGAGE ("Amendment
No.  1") is made on  July 9, 1996,  between READING AND  BATES BORNEO DRILLING
CO.,   LTD.,  an  Oklahoma  corporation  with  its  principal  office  at  901
Threadneedle, Suite 200,  Houston, Texas 77079 (the  "Owner"), and CHRISTIANIA
BANK OG  KREDITKASSE NEW YORK BRANCH having an  office at 11 West 42nd Street,
New York, New York 10036 as agent for the Banks (the "Mortgagee").

WHEREAS:

(A)   The Shipowner  is the sole owner  of the whole of  offshore drilling rig
      CHARLEY GRAVES Patente  No. 6618-76-CH,  registered in the  name of  the
      Shipowner under the laws and flag of the Republic of Panama (the "Rig");

(B)   By a Credit Agreement dated  as of April 30, 1996 (as  amended, restated
      or supplemented from time to time, the "Credit Agreement") among Reading
      &  Bates Corporation,  a  Delaware corporation  ("Holdings"), Reading  &
      Bates Drilling Co., an Oklahoma  corporation (the "Borrower"), the banks
      party thereto (the  "Banks"), Credit  Lyonnais New York  Branch, as  co-
      agent (the  "Co-Agent"), and Christiania  Bank og Kreditkasse,  New York
      Branch, as  agent (the "Agent"), it was agreed, among other things, that
      the  Banks  would make  available to  the  Borrower upon  the  terms and
      conditions therein  described a reducing revolving  credit facility (the
      "Facility")  in an  aggregate  amount at  any  time outstanding  of  One
      Hundred  Million United States  Dollars (US$100,000,000),  providing for
      the making of Loans  and the issuance of, and  participation in, Letters
      of Credit as contemplated therein.

(C)   To secure the obligations  of the Borrower with respect to  the Facility
      and  its  obligations   under  the  Credit  Agreement,  the   Owner  has
      authorized, executed  and delivered  a Subsidiary Guaranty  (as amended,
      restated or supplemented  from time to time,  the "Subsidiary Guaranty")
      dated April 30,  1996 in favor of the Agent and  the Banks and to secure
      the  obligations of the Owner  under the Subsidiary  Guaranty, the Owner
      has executed and delivered to the Mortgagee an  indenture of first naval
      mortgage dated April 30, 1996 with respect to the Rig  (the "Mortgage").
      The form of the Credit Agreement and the form of the Subsidiary Guaranty
      are attached  to the Mortgage  as Exhibits 1  and 2, respectively.   The
      mortgage was  protocolized by Public Deed No. 3124, dated May 6, 1996 of
      the  First Notary Public of the Circuit  of Panama, duly recorded in the
      Public  Registry  of  Panama   at  the  Microfilm  Section  (Mercantile)
      Microjacket N-12808, Roll 50020, Frame 0002 as of June 11, 1996.

(D)   By an Amendment to  the Credit Agreement dated as  of July 9, 1996  (the
      "Amendment")  (the  form  of  which  Amendment  without  attachments  is
      attached hereto as Exhibit  1) among Holdings, the Borrower,  the Banks,
      the Co-Agent  and the Agent, it  was agreed among other  things that the
      Banks  would increase  the amount  available to  the Borrower  under the
      Facility to an aggregate amount at  any time outstanding of One  Hundred
      Forty Million  United States  Dollars (US$140,000,000) subject  to semi-
      annual reductions as set forth therein.

(E)   In  order  to  secure  its  obligations  with  respect  to  the  Secured
      Indebtedness  under  the Subsidiary  Guaranty  and  the performance  and
      observance  of and  compliance  with all  of  the covenants,  terms  and
      conditions contained in the  Mortgage, as amended hereby, and  to induce
      the Banks  to enter into the  Amendment and for other  good and valuable
      consideration,  the   receipt  and   sufficiency  of  which   is  hereby
      acknowledged by the Owner,  the Owner has duly authorized  the execution
      and delivery of this Amendment to the Indenture of  First Naval Mortgage
      under and  in accordance with the  provisions of Chapter V,  Title IV of
      Book Second  of the  Code of  Commerce and pertinent  provisions of  the
      Civil Code and other legislations of the Republic of Panama.

      NOW, THEREFORE, in consideration of  the premises and of other good  and
valuable consideration,  receipt whereof  is hereby acknowledged,  the parties
hereto agree as follows:

      1.    DEFINITIONS AND INTERPRETATION

      1.01  Terms defined in the Mortgage shall have the same  meaning as used
            herein.

      1.02  The terms "Credit Agreement"  and "Subsidiary Guaranty" as defined
in Clause 2.01 of the Mortgage and as used in the Mortgage shall be  deemed to
refer  to the  Credit Agreement  as amended  by the  Amendment and  as further
amended,  restated or  supplemented  from time  to  time, and  the  Subsidiary
Guaranty as amended, restated or supplemented from time to time.

      1.03  The term "Other Rigs" shall be amended to refer to the J.W. McLEAN
as  registered under  the  laws of  the  Republic of  Panama  of 15,453  gross
registered tons  and 4,636 net registered tons, and shall also include (i) the
offshore drilling rig  HARVEY H. WARD owned by  HRB Rig Corporation documented
under the  laws and flag of the United  States of America with Official Number
642693 of  4,121 gross tons and  3,079 net registered tons,  (ii) the offshore
drilling rig Rig  41 owned by the RB Drilling Co. documented under the laws of
the Republic of  Panama with Patente Number 22365-95 of  10,078 gross tons and
3,024 net registered tons and  (iii) the offshore drilling rig SEILLEAN  to be
acquired by RB as contemplated by the Amendment.

      1.04  Each reference  in the  Mortgage to "this  Mortgage", "hereunder",
"hereof",  "herein"  or words  of  like import  shall  mean and  refer  to the
Mortgage as amended hereby.

2.    Power of Attorney.  
      2.01  The appearing parties each  confer a special power of  attorney on
Benedetti & Benedetti, lawyers of Panama,  Republic of Panama and any partners
in  the firm authorizing such firm  or any such partner  to take all necessary
steps to record this Amendment No. 1 in the appropriate registries of the City
of Panama and to appoint any substitute under this Power of Attorney.

3.    Continuing Effect.  

      3.01  Except  as expressly amended by this Amendment No. 1, the Mortgage
shall be and remain in full force and effect.


IN WITNESS WHEREOF, the parties hereto have caused this  Amendment No. 1 to be
duly executed on the day and year first above written.


                        READING AND BATES BORNEO DRILLING CO. LTD.


                        By_____________________________
                          Name: 
                          Title:


                        CHRISTIANIA BANK OG KREDITKASSE, NEW YORK BRANCH


                        By_____________________________
                          Name:
                          Title:



                        By_____________________________
                          Name:
                          Title:


                             NOTARIAL CERTIFICATE


I,  the  undersigned,  NOTARY PUBLIC,  duly  authorized,  admitted and  sworn,
residing and practicing in the State of New York, DO HEREBY CERTIFY that:

1.    _______________ as Attorney-in-Fact of READING AND BATES BORNEO DRILLING
      CO. LTD., INC. did sign the attached Amendment No. 1 to the Indenture of
      First Naval Mortgage  in my presence and the signature  appearing at the
      foot of said Amendment No.1 to the Indenture of First  Naval Mortgage is
      his/her authentic signature.

2.    Sufficient proof has been presented to me that he/she has  the right and
      power to  execute said Amendment No.  1 to the Indenture  of First Naval
      Mortgage on behalf of the above-mentioned corporation, as "Shipowner".

IN TESTIMONY WHEREOF,  I have hereunto subscribed my name  and affixed my seal
of office this ____ day of July, 1996.




                                    __________________________________
                                                Notary Public



                             NOTARIAL CERTIFICATE


I,  the  undersigned,  NOTARY PUBLIC,  duly  authorized,  admitted and  sworn,
residing and practicing in the State of New York, DO HEREBY CERTIFY that:


1.    ____________________   as  Vice   President  of   CHRISTIANIA  BANK   OG
      KREDITKASSE, NEW  YORK BRANCH did sign  the attached Amendment No.  1 to
      the Indenture of First  Naval Mortgage in my presence and  the signature
      appearing at  the foot of said Amendment No. 1 to the Indenture of First
      Naval Mortgage is his/her authentic signature.

2.    Sufficient proof has been presented to  me that he/she has the right and
      power to  execute said Amendment No.  1 to the Indenture  of First Naval
      Mortgage on behalf of the above-mentioned corporation, as "Mortgagee".

IN TESTIMONY WHEREOF, I have  hereunto subscribed my name and affixed  my seal
of office this ____ day of July, 1996.


                                    __________________________________
                                                Notary Public


                             NOTARIAL CERTIFICATE


I,  the  undersigned,  NOTARY PUBLIC,  duly  authorized,  admitted  and sworn,
residing and practicing in the State of New York, DO HEREBY CERTIFY that:


1.    ____________________   as   Vice  President   of  CHRISTIANIA   BANK  OG
      KREDITKASSE, NEW YORK BRANCH  did sign the  attached Amendment No. 1  to
      the Indenture of First Naval  Mortgage in my presence and  the signature
      appearing at the foot of said Amendment No. 1 to  the Indenture of First
      Naval Mortgage is his/her authentic signature.

2.    Sufficient proof  has been presented to me that he/she has the right and
      power to  execute said Amendment No.  1 to the Indenture  of First Naval
      Mortgage on behalf of the above-mentioned corporation, as "Mortgagee".

IN  TESTIMONY WHEREOF, I have hereunto subscribed  my name and affixed my seal
of office this ____ day of July, 1996.



                                    __________________________________
                                                Notary Public