EXHIBIT 99.1
 
                              TEXACO CAPITAL INC.
                             OFFICERS' CERTIFICATE
 
    Pursuant to Section 2.02 of the Indenture dated as of August 24, 1984, as
(1) supplemented and restated by the First Supplemental Indenture dated as of
January 31, 1990, (2) amended by the First Supplement to the First Supplemental
Indenture dated as of October 11, 1990, and (3) further amended by the Second
Supplement to the First Supplemental Indenture, dated as of August 5, 1997, (as
so supplemented and amended, the "Indenture") among Texaco Capital Inc., Texaco
Inc., and The Chase Manhattan Bank, as Trustee (the "Trustee"), the undersigned
officers of the Company hereby establish a Series of Securities having the
following terms and provisions:
 
        The Securities shall be designated "Series 1999 Medium-Term Notes" (the
    "Notes").
 
        The aggregate principal amount of the Notes authorized to be
    authenticated and delivered at any one time, subject to Sections 2.10, 2.11
    and 2.14 of the Indenture, is limited to $1,500,000,000 in U.S. dollars or
    the equivalent in non-U.S. dollar denominated currencies or currency units.
 
        Each Note may be denominated in authorized denominations in U.S.
    dollars, other currencies, or composite currencies (the "Specified
    Currency").
 
        The Notes will be offered at varying maturities of nine months or more
    from their dates of issue and may be subject to redemption at the option of
    the Company or repayment at the option of the holder prior to maturity.
 
        The authorized denominations of the Notes denominated in U.S. dollars
    will be integral multiples of $1,000. We will designate the authorized
    denominations of foreign currency Notes at the time of the issuance and sale
    of the Notes.
 
        The principal amount of a Note payable at maturity may be determined by
    either the relationship between a denominated currency and another currency
    or the relationship between the difference in the price of a specified
    commodity on certain specified dates or by reference to any other index.
 
        Each Note will bear interest at a fixed rate, which may be zero in the
    case of certain Notes issued at a price representing a discount from the
    principal amount payable at maturity, or at a floating rate determined by
    reference to the CD Rate, the Commercial Paper Rate, the Federal Funds Rate,
    LIBOR, the Treasury Rate, the Prime Rate, the CMT Rate, the Eleventh
    District Cost of Funds Rate, or any other Base Rate as adjusted by the
    Spread or Spread Multiplier, if any, applicable to such Note.
 
        Each Note will be represented by either a global security registered in
    the name of a nominee of The Depository Trust Company, as Depository, or
    other depository, or a certificate issued in definitive form, as set forth
    in the applicable Pricing Supplement. Beneficial interests in Book-Entry
    Notes will be shown on, and transfers thereof will be effected only through,
    records maintained by the Depository and its participants.
 
        Unless otherwise specified at the time of the issuance and sale of the
    Note, interest on each fixed rate note will accrue from its date of issue
    and will be payable semi-annually and at maturity, and interest on each
    floating rate note will accrue from its date of issue and will be payable
    monthly, quarterly, semi-annually or annually, and at maturity. The record
    date with respect to any interest payment date shall be the date fifteen
    calendar days (unless otherwise specified at the time of the issuance)
    immediately preceding such interest payment date whether or not such date
    shall be a business day.
 
        Unless otherwise specified at the time of the issuance and sale of the
    Note, payments in U.S. dollars of interest on Notes (other than interest
    payable at maturity or upon earlier redemption or repayment) will be made by
    mailing a check to the holder at the address of such holder appearing on the
    Register on the applicable record date. Notwithstanding the foregoing: (a)
    the Depository, as

    holder of the book-entry Note shall be entitled to receive payments of
    interest by wire transfer of immediately available funds; and (b) a holder
    of U.S. $10,000,000 or more in aggregate principal amount of certified Notes
    of like tenor and terms (or a holder of the equivalent thereof in a
    Specified Currency other than U.S. dollars) shall be entitled to receive
    such payments in U.S. dollars by wire transfer of immediately available
    funds, but only if appropriate payment instructions have been received in
    writing by the Paying Agent not less than fifteen days prior to the
    applicable Interest Payment Date. Unless otherwise specified at the time of
    issuance and sale of a Note, principal and any premium and interest payable
    at maturity or upon earlier redemption or repayment in respect of a Note
    will be paid in immediately available funds upon surrender of such Note at
    the office of the Paying Agent.
 
        The Company has initially appointed The Chase Manhattan Bank, 450 West
    33(rd) Street, New York, NY 10001 as Paying Agent.
 
        Each Note will indicate either that such Note cannot be redeemed prior
    to maturity or that such Note will be redeemable at the option of the
    Company on a date or dates specified prior to maturity at a price or prices
    determined at the time of issuance together with accrued interest to the
    date of redemption. Unless otherwise specified at the time of issuance, the
    Notes will not be subject to any sinking fund requirements. The Company may
    redeem any of the Notes which are redeemable and remain outstanding either
    in whole or from time to time in part, upon not more than 60 days' notice.
    If less than all of the Notes with like tenor and terms are to be redeemed,
    the Notes to be redeemed, the Notes to be redeemed shall be selected by the
    Trustee by such method as the Trustee shall deem fair and appropriate.
 
        The due and punctual payment of the principal of (and premium, if any)
    and interest, if any, on each Note, when and as the same shall become due
    and payable, whether at maturity or upon redemption, declaration or
    otherwise, shall be unconditionally guaranteed by Texaco Inc.
 
        Although the Indenture provides that the Company may terminate its
    obligations with respect to any Series of Securities by making certain
    deposits with the Trustee, the Notes shall provide that the Company will not
    exercise any such right with respect to the Notes.
 
        At the time of the issuance of each Note, any of the Chairman of the
    Board, the President, the Vice Presidents or the Treasurer (the "Company
    Officers") who is acting with respect to such issuance shall determine the
    terms of such Note provided that the Company Officer acting shall determine
    (taking into consideration any other contractual arrangements that may be in
    place, if any) with respect to such Notes that: (i) the aggregate principal
    amount of Notes issued does not exceed One Billion Five Hundred Million
    Dollars (or the equivalent in non-U.S. dollar-denominated currencies or
    currency units); and (ii) the all-in-interest cost shall not exceed 8%, such
    determination to be conclusively evidenced by the issuance of such Notes.
 
        The Notes shall be in the form of Exhibit C to the Distribution
    Agreement attached as Exhibit 99.2 to Texaco Inc.'s Current Report on Form
    8-K, filed with the Securities and Exchange Commission on April 28, 1999.
 
        Unless otherwise defined herein, capitalized terms used herein have the
    meanings set forth in the Indenture and the Notes.
 
                                                        J. F. Link
 
                                          --------------------------------------
                                                         CHAIRMAN
 
                                                       R. C. Gordan
 
                                          --------------------------------------
                                                        PRESIDENT
 
Dated: April 28, 1999