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                                                                     EXHIBIT 3.1



                     RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                               WESTERN ATLAS INC.



    1.     The name of the Corporation (which is hereinafter referred to as the
Corporation) is "Western Atlas Inc."

    2.     The original Certificate of Incorporation was filed with the
Secretary of State of the State of Delaware on February 13, 1984, under the
name Litton Datamedics, Inc.

    3.     This Restated Certificate of Incorporation has been duly proposed by
resolutions adopted and declared advisable by the Board of Directors of the
Corporation, duly adopted by the sole stockholder of the Corporation and duly
executed and acknowledged by the officers of the Corporation in accordance with
the provisions of Sections 103, 242 and 245 of the General Corporation Law of
the State of Delaware.

    4.     The text of the Certificate of Incorporation of the Corporation is
hereby amended and restated to read in its entirety as follows:

    FIRST:  The name of the Corporation is Western Atlas Inc.

    SECOND:  The registered office of the Corporation is located at 32
Loockerman Square, Suite L-100, in the City of Dover, in the County of Kent, in
the State of Delaware.  The name of its registered agent is The Prentice-Hall
Corporation System, Inc.

    THIRD:  The nature of the business or purposes to be conducted or promoted
is:  To engage in any lawful act or activity for which corporations may be
organized under the General Corporation Law of Delaware.

    FOURTH:  Shares, Classes, Preferences and Rights of Stock.

Section 1.  Authorized Shares

      The total number of shares of capital stock which the Corporation shall
have authority to issue is 175,000,000 shares consisting of:

           (a)   150,000,000 shares of Common Stock having a par value of $1.00
per share; and

           (b)   25,000,000 shares of Preferred Stock having a par value of
$1.00 per share.
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      Effective upon the filing of this Restated Certificate of Incorporation
with the Secretary of State of the State of Delaware, each issued share of
Common Stock, par value $1.00 per share, of the Corporation is changed and
reclassified into 45,816.16 shares of Common Stock, par value $1.00 per share,
of the Corporation.

Section 2.  Preferred Stock -- General

      The Preferred Stock may be issued from time to time in one or more
series.  The Board of Directors is hereby authorized to provide for the
issuance of shares of Preferred Stock in series and, by filing a certificate
pursuant to the applicable law of the State of Delaware (hereinafter referred
to as a "Preferred Stock Designation"), to establish from time to time the
number of shares to be included in each such series, and to fix the
designation, powers, preferences and rights of the shares of each such series
and the qualifications, limitations and restrictions thereof.  The authority of
the Board of Directors with respect to each series shall include, but not be
limited to, determination of the following:

           (a)   the designation of the series, which may be by distinguishing
      number, letter or title;

           (b)   the number of shares of the series, which number the Board of
      Directors may thereafter (except where otherwise provided in the
      Preferred Stock Designation) increase or decrease (but not below the
      number of shares thereof then outstanding);

           (c)   whether dividends, if any, shall be cumulative or
      noncumulative and the dividend rate of the series;

           (d)   the dates at which dividends, if any, shall be payable;

           (e)   the redemption rights and price or prices, if any, for shares
      of the series;

           (f)   the terms and amount of any sinking fund provided for the
      purchase or redemption of shares of the series;

           (g)   the amounts payable on shares of the series in the event of
      any voluntary or involuntary liquidation, dissolution or winding up of
      the affairs of the Corporation;

           (h)   whether the shares of the series shall be convertible into
      shares of any other class or series, or any other security, of the
      Corporation or any other corporation, and, if so, the specification of
      such other class or series or such other security, the conversion price
      or prices or rate or rates, any adjustments thereof, the date or dates as
      of which such shares shall be convertible and all other terms and
      conditions upon which such conversion may be made;



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           (i)   restrictions on the issuance of shares of the same series or
      of any other class or series; and

           (j)   the voting rights, if any, of the holders of shares of the
      series.

      The Common Stock shall be subject to the express terms of the Preferred
Stock and any series thereof.  Each share of Common Stock shall be equal to
each other share of Common Stock.  The holders of shares of Common Stock shall
be entitled to one vote for each such share upon all proposals presented to the
stockholders on which the holders of Common Stock are entitled to vote.

      Except as may be provided in this Certificate of Incorporation or in a
Preferred Stock Designation, the Common Stock shall have the exclusive right to
vote for the election of directors and for all other purposes, and holders of
Preferred Stock shall not be entitled to receive notice of any meeting of
stockholders at which they are not entitled to vote.  The number of authorized
shares of Preferred Stock may be increased or decreased (but not below the
number of shares thereof then outstanding) by the affirmative vote of the
holders of a majority of the outstanding Common Stock, without a vote of the
holders of the Preferred Stock, or of any series thereof, unless a vote of any
such holders is required pursuant to any Preferred Stock Designation.

      The Corporation shall be entitled to treat the person in whose name any
share of its stock is registered as the owner thereof for all purposes and
shall not be bound to recognize any equitable or other claim to, or interest
in, such share on the part of any other person, whether or not the Corporation
shall have notice thereof, except as expressly provided by applicable law.

      FIFTH:  The following provisions are inserted for the management of the
business and for the conduct of the affairs of the Corporation, and for further
definition, limitation and regulation of the powers of the Corporation and of
its directors and stockholders:

Section 1.  Directors

      Subject to the rights of the holders of any series of Preferred Stock or
any other series or class of stock, as provided herein or in any Preferred
Stock Designation, to elect additional directors under specific circumstances,
the number of directors of the Corporation shall be fixed from time to time
exclusively by the Board of Directors pursuant to a resolution adopted by a
majority of the total number of directors that the Corporation would have if
there were no vacancies, but shall not be less than three.  Election of
directors need not be by ballot unless the By-laws so provide.

      The directors, other than those who may be elected by the holders of any
series of Preferred Stock or any other series or class of stock, as provided
herein or in any Preferred Stock Designation shall be divided into three
classes, as nearly equal in number as possible.  One class of directors shall
be initially elected for a term expiring





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at the annual meeting of stockholders to be held in 1995, another class shall
be initially elected for a term expiring at the annual meeting of stockholders
to be held in 1996, and another class shall be initially elected for a term
expiring at the annual meeting of stockholders to be held in 1997.  Members of
each class shall hold office until their successors are elected and shall have
qualified.  At each succeeding annual meeting of the stockholders of the
Corporation, the successors of the class of directors whose term expires at
that meeting shall be elected by a plurality vote of all votes cast at such
meeting to hold office for a term expiring at the annual meeting of
stockholders held in the third year following the year of their election.

      Subject to the rights of the holders of any series of Preferred Stock or
any other series or class of stock, as provided herein or in any Preferred
Stock Designation, to elect additional directors under specific circumstances,
any director may be removed from office at any time, but only for cause and
only by the affirmative vote of the holders of at least 80 percent of the
voting power of the then outstanding capital stock of the Corporation entitled
to vote generally in the election of directors (the "Voting Stock"), voting
together as a single class.

Section 2.  Power to Amend By-laws

      The By-laws may be altered or repealed and new By-laws may be adopted (1)
at any annual or special meeting of stockholders if notice of the proposed
alteration, repeal or adoption of the new By-law or By-laws be contained in the
notice of such special meeting by the affirmative vote of a majority of the
stock issued and outstanding and entitled to vote thereat, provided, however,
that any proposed alteration or repeal of, or the adoption of any By-law
inconsistent with, Section 1, 3 or 4 of Article III of the By-laws by the
stockholders shall require the affirmative vote of at least 80 percent of the
stock issued and outstanding and entitled to vote thereat, or (2) by the
affirmative vote of a majority of the members present at any regular meeting of
the Board of Directors, or at any special meeting of the Board of Directors, if
notice of the proposed alteration, repeal or new By-law or By-laws to be made,
be contained in the notice of such special meeting.

Section 3.  Stockholders' Action -- Only By Meeting; Special Meetings

      Any action required or permitted to be taken by the stockholders shall be
taken only at an annual or special meeting of such stockholders and not by
consent in writing.  Special meetings of the stockholders for any purpose or
purposes shall be called only upon a request in writing therefor, stating the
purpose or purposes thereof, delivered to the Chairman of the Board, the
President, or the Secretary, signed by a majority of the directors, or by
resolution of the Board of Directors or the Executive Committee thereof.





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      SIXTH:     Elimination of Certain Liability of Directors and
Indemnification.

Section 1.  Elimination of Certain Liability of Directors

      No director shall be personally liable to the Corporation or its
stockholders for monetary damages for breach of fiduciary duty by such director
as a director, except for liability (i) for any breach of the director's duty
of loyalty to the Corporation or its stockholders, (ii) for acts or omissions
not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the General Corporation Law of the
State of Delaware, or (iv) for any transaction from which the director derived
an improper personal benefit.  Neither the amendment nor repeal of Section 1 of
this Article SIXTH shall eliminate or reduce the effect of Section 1 of this
Article SIXTH in respect of any matter occurring, or any cause of action, suit
or claim that, but for Section 1 of this Article SIXTH would accrue or arise,
prior to such amendment or repeal.  If the Delaware General Corporation Law is
amended after approval by the stockholders of this Article SIXTH to authorize
corporate action further eliminating or limiting the personal liability of
directors, then the liability of a director of the Corporation shall be
eliminated or limited to the fullest extent permitted by the Delaware General
Corporation Law, as so amended from time to time.

Section 2.  Indemnification and Insurance

      (a)  Right to Indemnification.  Each person who was or is made a party or
is threatened to be made a party to or is involved in any action, suit or
proceeding, whether civil, criminal, administrative or investigative
(hereinafter a "proceeding"), by reason of the fact that he or she, or a person
of whom he or she is the legal representative, is or was a director or officer
of the Corporation or is or was serving at the request of the Corporation as a
director, officer, employee or agent of another corporation or of a
partnership, joint venture, trust or other enterprise, including service with
respect to employee benefit plans maintained or sponsored by the Corporation,
whether the basis of such proceeding is alleged action in an official capacity
as a director, officer, employee or agent or in any other capacity while
serving as a director, officer, employee or agent, shall be indemnified and
held harmless by the Corporation to the fullest extent authorized by the
Delaware General Corporation Law, as the same exists or may hereafter be
amended (but, in the case of any such amendment, only to the extent that such
amendment permits the Corporation to provide broader indemnification rights
than said Law permitted the Corporation to provide prior to such amendment),
against all expense, liability and loss (including attorneys' fees, judgments,
fines, excise taxes pursuant to the Employee Retirement Income Security Act of
1974 or penalties and amounts paid or to be paid in settlement) reasonably
incurred or suffered by such person in connection therewith and such
indemnification shall continue as to a person who has ceased to be a director,
officer, employee or agent and shall inure to the benefit of his or her heirs,
executors and administrators; provided, however, that, except as provided in
paragraph (b) hereof, the Corporation shall indemnify any such person seeking
indemnification in connection with a proceeding (or part thereof) initiated by
such person only if such proceeding (or part thereof) was authorized by the
Board of





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Directors of the Corporation.  The right to indemnification conferred in this
Section shall be a contract right and shall include the right to be paid by the
Corporation the expenses incurred in defending any such proceeding in advance
of its final disposition; provided, however, that, if the Delaware General
Corporation Law requires, the payment of such expenses incurred by a director
or officer in his or her capacity as a director or officer (and not in any
other capacity in which service was or is rendered by such person while a
director or officer, including, without limitation, service to an employee
benefit plan) in advance of the final disposition of a proceeding, shall be
made only upon delivery to the Corporation of an undertaking, by or on behalf
of such director or officer, to repay all amounts so advanced if it shall
ultimately be determined  that such director or officer is not entitled to be
indemnified under this Section or otherwise.  The Corporation may, by action of
its Board of Directors, provide indemnification to employees and agents of the
Corporation with the same scope and effect as the foregoing indemnification of
directors and officers.

      (b)  Right of Claimant to Bring Suit.  If a claim under paragraph (a) of
this Section is not paid in full by the Corporation within thirty days after a
written claim has been received by the Corporation, the claimant may at any
time thereafter bring suit against the Corporation to recover the unpaid amount
of the claim and, if successful in whole or in part, the claimant shall be
entitled to be paid also the expense of prosecuting such claim.  It shall be a
defense to any such action (other than an action brought to enforce a claim for
expenses incurred in defending any proceeding in advance of its final
disposition where the required undertaking, if any is required, has been
tendered to the Corporation) that the claimant has not met the standard of
conduct which makes it permissible under the Delaware General Corporation Law
for the Corporation to indemnify the claimant for the amount claimed, but the
burden of proving such defense shall be on the Corporation.  Neither the
failure of the Corporation (including its Board of Directors, independent legal
counsel, or its stockholders) to have made a determination prior to the
commencement of such action that indemnification of the claimant is proper in
the circumstances because he or she has met the applicable standard of conduct
set forth in the Delaware General Corporation Law, nor an actual determination
by the Corporation (including its Board of Directors, independent legal counsel
or its stockholders) that the claimant has not met such applicable standard of
conduct, shall be a defense to the action or create a presumption that the
claimant has not met the applicable standard of conduct.

      (c)  Non-Exclusivity of Rights.  The right to indemnification and the
payment of expenses incurred in defending a proceeding in advance of its final
disposition conferred in this Section shall not be exclusive of any other right
which any person may have or hereafter acquire under any statute, provision of
this Restated Certificate of Incorporation, by- law, agreement, vote of
stockholders or disinterested directors or otherwise.

      (d)  Insurance.  The Corporation may maintain insurance, at its expense,
to protect itself and any director, officer, employee or agent of the
Corporation or any person serving at the request of the Corporation as a
director, officer, employee or agent of





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another corporation or of a partnership, joint venture, trust or other
enterprise, including service with respect to employee benefit plans maintained
or sponsored by the Corporation, against any such expense, liability or loss,
whether or not the Corporation would have the power to indemnify such person
against such expense, liability or loss under the Delaware General Corporation
Law.

      SEVENTH:  The Corporation reserves the right to amend, change, or repeal
any provision contained in the Certificate of Incorporation in the manner now
or hereafter prescribed by law, and all rights and powers conferred herein on
stockholders, directors, and officers are subject to this reserved power.
Notwithstanding anything contained in this Certificate of Incorporation to the
contrary, the affirmative vote of the holders of at least 80 percent of the
voting power of the then outstanding Voting Stock, voting together as a single
class, shall be required to amend or repeal Article FIFTH or adopt any
provision inconsistent therewith or to amend or repeal this Article SEVENTH.

      IN WITNESS WHEREOF, said Western Atlas Inc. has caused this Restated
Certificate of Incorporation to be signed by its Chairman of the Board and
attested by its Secretary this 17th day of March, 1994.

                                     WESTERN ATLAS INC.



                                     By: 
                                         ---------------------------------
                                         Chairman of the Board



Attest: 
        --------------------------
        Secretary





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