EXHIBIT 5.1

 
                                                                   July 27, 1998


Schlumberger Limited
277 Park Avenue
New York, New York  10172

Gentlemen:

          I am General Counsel of Schlumberger Limited ("Schlumberger"), and, as
set forth in the Registration Statement on Form S-4 (the "Registration
Statement") filed by Schlumberger under the Securities Act of 1933, as amended,
relating to 45,000,000 shares of Common Stock, par value $.01 per share, of
Schlumberger (the "Shares"), I am passing upon for you certain legal matters in
connection with the securities so offered for Schlumberger.  As set forth in the
Registration Statement, the Shares are the maximum number of shares deliverable
upon consummation of the merger of Schlumberger OFS, Inc. ("OFS"), a wholly
owned subsidiary of Schlumberger Technology Corporation ("STC"), with and into
Camco International Inc. ("Camco") pursuant to a Merger Agreement dated as of
June 18, 1998 (the "Merger Agreement") among STC, OFS and Camco.  At your
request, this opinion of counsel is being furnished for filing as Exhibit 5 to
the Registration Statement.

          I am a member only of the New York and Texas bars, and I am not
admitted to practice in, nor do I hold myself out as an expert on the laws of,
the Netherlands Antilles.  I have, however, consulted with the law firm of
Smeets Thesseling Van Bokhorst Spigt, which is qualified to practice in the
Netherlands Antilles and which I consider an expert on the laws of such
jurisdiction.  Insofar as the opinions expressed below involve conclusions as to
matters governed by the laws of the Netherlands Antilles, I am relying on the
opinion of such counsel.

          In my capacity as General Counsel of Schlumberger, I am familiar with
the Deed of Incorporation, as amended, and the By-Laws of Schlumberger and have
familiarized myself with the Merger Agreement and have examined all statutes and
other records, instruments and documents pertaining to Schlumberger that I have
deemed necessary to examine for the purposes of this opinion.

          Based upon my examination as aforesaid, I am of the opinion that the
Shares have been duly authorized by resolution of the Board of Directors of
Schlumberger and, when delivered pursuant to the Merger Agreement, will be
validly issued, fully paid and nonassessable.

          I hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to me under the caption "Legal
Matters" in the Proxy Statement/Prospectus contained in the Registration
Statement.

                                 Very truly yours,


                                 /s/ David S. Browning