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                                                                    EXHIBIT 10.6
                   [MILLER EXPLORATION COMPANY - LETTERHEAD]


                                 May 18, 1999



Mr. C.E. "Gene" Miller
Eagle Investment Inc.
3140 Logan Valley Rd.
Traverse City, MI  49685

          RE:  Participation Letter Agreement
               Allar #6 Well
               Midway Dome
               Lamar County, MS

Dear Gene,

          This Participation Letter Agreement (hereinafter referred to as "the
Agreement") is written for the purpose of setting forth the terms and
conditions between Miller Exploration Company ("Miller") and Eagle Investment
Inc. ("Eagle") with respect to Eagle's participation in the drilling of the
Miller Allar #6 well ("Allar#6") located on the Midway Dome Prospect, Lamar
County, MS.  The terms and conditions of Eagle's participation are as follows:

          1.  Eagle agrees that concurrently with the execution of this
              Agreement, Eagle shall pay to Miller twenty six and two thirds
              percent (26.67%) of the one million three hundred and forty
              thousand dollar ($1,340,000.00) estimated dry hole costs
              attributable to the Allar#6. Eagle recognizes that the amount of
              the AFE is an estimate only, and Eagle shall pay twenty six and
              two thirds percent (26.67%) of the actual cost and expense of
              drilling the Allar#6 as such costs are determined under the terms
              of this Agreement and the March 1, 1999 Joint Operating Agreement
              ("Operating Agreement") governing the operations of the Allar#6,
              whether incurred prior to or after the date of this Agreement to
              production casing point as defined in the Operating Agreement.
              Such costs shall include, if applicable and by way of
              illustration and not limitation, the following: permits; staking
              and surveying; legal fees as relating to title examination and
              curative, spacing; fee of consultants; rights-of-way; surface
              leases; damages; roads, canals and locations; drilling mud and
              chemicals; rentals and services; drilling contractor costs;
              supplies and materials; fuel and water, cement and services;
              transportation; tubular goods; well head equipment (casinghead and
              slips); logging; coring; surveys (velocity, etc,); analyses or
              reports, travel and telephone expenses of Operator's employees
              directly related to the costs described herein; drafting;
              reproduction; plugging and abandoning. However, Eagle shall not
              pay leasehold or brokerage expenses and shall not pay a prospect
              fee and/or any geological or geophysical expenses incurred by
              Miller in the Midway Dome Prospect.

          2.  It is agreed that contemporaneously with the execution of this
              Agreement by Eagle, Miller shall assign to Eagle twenty percent
              (20%) of 8/8ths of those portions of the oil, gas and mineral
              leases and a like interest in any other oil, gas and mineral
              leases owned or controlled by Miller in Section 31-T4N-15W, Lamar
              County, MS inclusive of the




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Page 2
Eagle Investment
Allar #6 Participation Agreement



               Allar#6 640 acre unit (hereinafter called "Allar#6 Unit Leases").
               The Allar#6 Unit Leases are hereby subject to the Operating
               Agreement. In the event of conflict or inconsistency between the
               terms and provisions of this Agreement and those of the Operating
               Agreement or the Joint Venture Agreement, the terms and
               provisions of this Agreement shall prevail as to the interests of
               the parties hereunder.

          3.   Eagle will have the right, but not the obligation to participate
               for twenty percent (20%) interest in any completion attempt on
               the Allar#6. It is agreed and understood that Eagle's after
               casing point interest in the Allar#6 will be tweny percent (20%).

          4.   In the event Miller proposes a well to be drilled offsetting the
               Miller Allar #3 well in Section 20, T4N-R15W, Eagle will have the
               option to participate under the same terms and conditions as its
               participation in the Allar #6. However, Miller may elect to
               assign Eagle a two percent (2%) of 8/8ths overriding royalty
               interest in the leases included in the unit designated for the
               above reference offset well in lieu of Eagle's participation.

          Should the foregoing meet with your approval, please so indicate where
provided below and return one executed copy to the undersigned at MEXP's Houston
office. Upon receipt Miller will immediately provide Eagle with an assignment of
the Allar #6 unit leases.

                                        Sincerely,

                                        MILLER EXPLORATION COMPANY



                                        /s/ C.W. Measley, Jr.
                                        ---------------------------------------
                                        C.W. Measley, Jr.
                                        Manager Land & Acquisitions

AGREED TO AND ACCEPTED THIS 19TH DAY OF MAY, 1999.

EAGLE INVESTMENTS INC.

BY: /s/ C.E. Miller
   -------------------------------
C.E. ("Gene") Miller-President



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