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                                                                    Exhibit 4.14

                          THIRD SUPPLEMENTAL INDENTURE

          THIRD SUPPLEMENTAL INDENTURE (this "Supplemental Indenture"), dated as
of April 24, 2002, among Modern Acquisition, Inc., a Delaware corporation, (the
"Guaranteeing Subsidiary"), and State Street Bank and Trust Company, as trustee
under the indenture referred to below (the "Trustee").

                              W I T N E S S E T H :

          WHEREAS, Dresser, Inc., a Delaware Corporation (the "Company"), and
the existing Guarantors (as defined in the Indenture referred to herein) have
heretofore executed and delivered to the Trustee an indenture (the "Indenture"),
dated as of April 10, 2001, and as amended on June 4, 2001 and June 12, 2001,
providing for the issuance of an aggregate principal amount of up to
$300,000,000 of 9 3/8% Senior Subordinated Notes due 2011 (the "Notes");

          WHEREAS, the Indenture provides that under certain circumstances the
Guaranteeing Subsidiary shall execute and deliver to the Trustee a supplemental
indenture pursuant to which the Guaranteeing Subsidiary shall unconditionally
guarantee all of the Company's Obligations under the Notes and the Indenture on
the terms and conditions set forth herein (the "Guarantee"); and

          WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee is
authorized to execute and deliver this Supplemental Indenture.

          NOW THEREFORE, in consideration of the foregoing and for other good
and valuable consideration, the receipt of which is hereby acknowledged, the
Guaranteeing Subsidiary and the Trustee mutually covenant and agree for the
equal and ratable benefit of the Holders of the Notes as follows:

          1.   CAPITALIZED TERMS. Capitalized terms used herein without
definition shall have the meanings assigned to them in the Indenture.

          2.   AGREEMENT TO GUARANTEE. The Guaranteeing Subsidiary hereby agrees
as follows:

               (a)  Along with all Guarantors named in the Indenture, to jointly
                    and severally Guarantee to each Holder of a Note
                    authenticated and delivered by the Trustee and to the
                    Trustee and its successors and assigns, irrespective of the
                    validity and enforceability of the Indenture, the Notes or
                    the obligations of the Company hereunder or thereunder,
                    that:

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                    (i)   the principal of and interest on the Notes will be
               promptly paid in full when due, whether at maturity, by
               acceleration, redemption or otherwise, and interest on the
               overdue principal of and interest on the Notes, if any, if
               lawful, and all other obligations of the Company to the Holders
               or the Trustee hereunder or thereunder will be promptly paid in
               full or performed, all in accordance with the terms hereof and
               thereof; and

                    (ii)  in case of any extension of time of payment or renewal
               of any Notes or any of such other obligations, that same will be
               promptly paid in full when due or performed in accordance with
               the terms of the extension or renewal, whether at stated
               maturity, by acceleration or otherwise. Failing payment when due
               of any amount so guaranteed or any performance so guaranteed for
               whatever reason, the Guarantors shall be jointly and severally
               obligated to pay the same immediately.

               (b)  The obligations hereunder shall be unconditional,
                    irrespective of the validity, regularity or enforceability
                    of the Notes or the Indenture, the absence of any action to
                    enforce the same, any waiver or consent by any Holder of the
                    Notes with respect to any provisions hereof or thereof, the
                    recovery of any judgment against the Company, any action to
                    enforce the same or any other circumstance which might
                    otherwise constitute a legal or equitable discharge or
                    defense of a guarantor.

               (c)  The following is hereby waived: diligence, presentment,
                    demand of payment, filing of claims with a court in the
                    event of insolvency or bankruptcy of the Company, any right
                    to require a proceeding first against the Company, protest,
                    notice and all demands whatsoever.

               (d)  This Guarantee shall not be discharged except by complete
                    performance of the obligations contained in the Notes and
                    the Indenture or pursuant to Section 6 hereof.

               (e)  If any Holder or the Trustee is required by any court or
                    otherwise to return to the Company, the Guarantors, or any
                    custodian, Trustee, liquidator or other similar official
                    acting in relation to either the Company or the Guarantors,
                    any amount paid by either to the Trustee or such Holder,
                    this Guarantee, to the extent theretofore discharged, shall
                    be reinstated in full force and effect.

               (f)  No Guaranteeing Subsidiary shall be entitled to any right of
                    subrogation in relation to the Holders in respect of any
                    obligations guaranteed hereby until payment in full of all
                    obligations guaranteed hereby.

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               (g)  As between the Guarantors, on the one hand, and the Holders
                    and the Trustee, on the other hand, (x) the maturity of the
                    obligations guaranteed hereby may be accelerated as provided
                    in Article 6 of the Indenture for the purposes of this
                    Guarantee, notwithstanding any stay, injunction or other
                    prohibition preventing such acceleration in respect of the
                    obligations guaranteed hereby, and (y) in the event of any
                    declaration of acceleration of such obligations as provided
                    in Article 6 of the Indenture, such obligations (whether or
                    not due and payable) shall forthwith become due and payable
                    by the Guarantors for the purpose of this Guarantee.

               (h)  The Guarantors shall have the right to seek contribution
                    from any non-paying Guarantor so long as the exercise of
                    such right does not impair the rights of the Holders under
                    the Guarantee.

               (i)  Pursuant to Section 11.03 of the Indenture, after giving
                    effect to any maximum amount and any other contingent and
                    fixed liabilities that are relevant under any applicable
                    Bankruptcy or fraudulent conveyance laws (including, without
                    limitation, all Senior Debt of such Guarantor), and after
                    giving effect to any collections from, rights to receive
                    contribution from or payments made by or on behalf of any
                    other Guarantor in respect of the obligations of such other
                    Guarantor under Article 11 of the Indenture shall result in
                    the obligations of such Guarantor under its Guarantee not
                    constituting a fraudulent transfer or conveyance.

          3.   SUBORDINATION. The Obligations of the Guaranteeing Subsidiary
under its Guarantee pursuant to this Supplemental Indenture shall be junior and
subordinated to the Senior Debt of such Guaranteeing Subsidiary on the same
basis as the Notes are junior and subordinated to the Senior Debt of the
Company. For the purposes of the foregoing sentence, the Trustee and the Holders
shall have the right to receive and/or retain payments by such Guaranteeing
Subsidiary only at such time as they may receive and/or retain payments in
respect of the Notes pursuant to the Indenture, including Article 10 thereof.

          4.   EXECUTION AND DELIVERY. The Guaranteeing Subsidiary agrees that
the Guarantees shall remain in full force and effect notwithstanding any failure
to endorse on each Note a notation of such Guarantee.

          5.   Guaranteeing Subsidiary May Consolidate, Etc. on Certain Terms.

               (a)  No Guaranteeing Subsidiary may consolidate with or merge
                    with or into (whether or not such Guarantor is the surviving
                    Person) another corporation, Person or entity whether or not
                    affiliated with such Guarantor unless:

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                    (i)   subject to Section 11.05 of the Indenture, the Person
               formed by or surviving any such consolidation or merger (if other
               than a Guarantor or the Company) shall be a corporation organized
               and validly existing under the laws of the United States or any
               state thereof or the District of Columbia, and unconditionally
               assumes all the obligations of such Guarantor, pursuant to a
               supplemental indenture in form and substance reasonably
               satisfactory to the Trustee, under the Notes, the Indenture and
               the Guarantee on the terms set forth herein or therein;

                    (ii)  immediately after giving effect to such transaction,
               no Default or Event of Default exists; and

                    (iii) the Company would be permitted, immediately after
               giving effect to such transaction, to incur at least $1.00 of
               additional Indebtedness (other than Permitted Indebtedness)
               pursuant to Section 4.09 of the Indenture.

               (b)  In case of any such consolidation, merger, sale or
                    conveyance and upon the assumption by the successor Person,
                    by supplemental indenture, executed and delivered to the
                    Trustee and satisfactory in form to the Trustee, of the
                    Guarantee endorsed upon the Notes and the due and punctual
                    performance of all of the covenants and conditions of the
                    Indenture to be performed by the Guarantor, such successor
                    Person shall succeed to and be substituted for the Guarantor
                    with the same effect as if it had been named herein as a
                    Guarantor. Such successor Person thereupon may cause to be
                    signed any or all of the Guarantees to be endorsed upon all
                    of the Notes issuable hereunder which theretofore shall not
                    have been signed by the Company and delivered to the
                    Trustee. All the Guarantees so issued shall in all respects
                    have the same legal rank and benefit under the Indenture as
                    the Guarantees theretofore and thereafter issued in
                    accordance with the terms of the Indenture as though all of
                    such Guarantees had been issued at the date of the execution
                    hereof.

               (c)  Except as set forth in Articles 4 and 5 of the Indenture,
                    and notwithstanding clauses(a)(iii) above, nothing contained
                    in the Indenture or in any of the Notes shall prevent any
                    consolidation or merger of a Guarantor with or into the
                    Company or another Guarantor, or shall prevent any sale or
                    conveyance of the property of a Guarantor as an entirety or
                    substantially as an entirety to the Company or another
                    Guarantor.

          6.   RELEASES. In the event of a sale or other disposition of all of
the assets of any Guarantor, by way of merger, consolidation or otherwise, or a
sale or other disposition of all to the capital stock of any Guarantor, then
such Guarantor (in the event of a sale or other disposition, by way of merger,
consolidation or otherwise, of all of the capital stock of such

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Guarantor) or the corporation acquiring the property (in the event of a sale or
other disposition of all or substantially all of the assets of such Guarantor)
will be released and relieved of any obligations under its Guarantee; provided
that the Net Cash Proceeds of such sale or other disposition are applied in
accordance with the applicable provisions of the Indenture, including without
limitation Section 4.10 of the Indenture. Upon delivery by the Company to the
Trustee of an Officers' Certificate and an Opinion of Counsel to the effect that
such sale or other disposition was made by the Company in accordance with the
applicable provisions of the Indenture, including without limitation Section
4.10 of the Indenture, the Trustee shall execute any documents reasonably
required in order to evidence the release of any Guarantor from its obligations
under its Guarantee.

          Any Guarantor not released from its obligations under its Guarantee
shall remain liable for the full amount of principal of and interest on the
Notes and for the other obligations of any Guarantor under the Indenture as
provided in Article 11 of the Indenture.

          7.   NO RECOURSE AGAINST OTHERS. No past, present or future director,
officer, employee, incorporator, stockholder or agent of any Guaranteeing
Subsidiary, as such, shall have any liability for any obligations of the Company
or any Guaranteeing Subsidiary under the Notes, any Guarantees, the Indenture or
this Supplemental Indenture or for any claim based on, in respect of, or by
reason of, such obligations or their creation. Each Holder of the Notes by
accepting a Note waives and releases all such liability. The waiver and release
are part of the consideration for issuance of the Notes. Such waiver may not be
effective to waive liabilities under the federal securities laws and it is the
view of the Commission that such a waiver is against public policy.

          8.   NEW YORK LAW TO GOVERN. THE INTERNAL LAW OF THE STATE OF NEW YORK
SHALL GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE WITHOUT GIVING
EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE
APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

          9.   COUNTERPARTS. The parties may sign any number of copies of this
Supplemental Indenture. Each signed copy shall be an original, but all of them
together represent the same instrument.

          10.  EFFECT OF HEADINGS. The Section headings herein are for
convenience only and shall not affect the construction hereof.

          11.  THE TRUSTEE. The Trustee shall not be responsible in any manner
whatsoever for or in respect of the validity or sufficiency of this Supplemental
Indenture or for or in respect of the recitals contained herein, all of which
recitals are made solely by the Guaranteeing Subsidiary and the Company.

          IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed and attested, all as of the date first above
written.

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Dated:  April 24, 2002


                                        MODERN ACQUISITION, INC.


                                        By: /s/ JAMES A. NATTIER
                                            ------------------------------------
                                        Name:  James A. Nattier
                                        Title: Vice President


                                        STATE STREET BANK AND TRUST
                                        COMPANY , as Trustee


                                        By: /s/ PHILIP G. KANE
                                            ------------------------------------
                                        Name:  Philip G. Kane, Jr.
                                        Title: Vice President