THE SECURITIES  REPRESENTED  BY THIS NOTE AND THE COMMON STOCK ISSUABLE  THEREBY
HAVE NOT BEEN  REGISTERED  UNDER THE  SECURITIES  ACT OF 1933,  AS AMENDED  (THE
"SECURITIES ACT") OR ANY OTHER APPLICABLE SECURITIES LAWS AND, ACCORDINGLY,  THE
SECURITIES REPRESENTED BY THIS NOTE MAY NOT BE TRANSFERRED EXCEPT PURSUANT TO AN
EFFECTIVE  REGISTRATION  STATEMENT  UNDER,  OR  IN  A  TRANSACTION  EXEMPT  FROM
REGISTRATION  UNDER,  THE  SECURITIES  ACT  AND IN  ACCORDANCE  WITH  ANY  OTHER
APPLICABLE SECURITIES LAWS.

THIS NOTE MAY BE SUBORDINATE TO CERTAIN  INDEBTEDNESS OF BLACK WARRIOR  WIRELINE
CORP. AS AND TO THE EXTENT SET FORTH IN THAT CERTAIN  AGREEMENT FOR PURCHASE AND
SALE DATED AS OF THE DATE HEREOF  BETWEEN BLACK WARRIOR  WIRELINE  CORP. AND ST.
JAMES CAPITAL PARTNERS, L.P.


                          BLACK WARRIOR WIRELINE CORP.
                     $10,000,000 CONVERTIBLE PROMISSORY NOTE


$10,000,000                       Houston, Texas                January 23, 1998


       BLACK WARRIOR WIRELINE CORP., a Delaware corporation  (hereinafter called
the  "Company,"  which term  includes  any  directly  or  indirectly  controlled
subsidiaries or successor entities), for value received,  hereby promises to pay
to St. James Capital Partners, L.P., a Delaware limited partnership (hereinafter
called  "Holder"),  or its  registered  assigns,  the principal sum of up to Ten
Million  Dollars  ($10,000,000),  together  with  interest on the amount of such
principal  sum from time to time  outstanding,  payable in  accordance  with the
terms set forth below.  It is the  intention  of the parties that the  principal
sums of this Note shall be  advanced in multiple  Advances  (as defined  below),
subject to the satisfaction of the conditions precedent set forth in Section 1.8
of the Agreement of Purchase and Sale between the Company and Holder dated as of
the date hereof. No Advance shall be made under this Note if an Event of Default
(as defined  below) exists or would exist but for the passage of time.  Interest
under this Note shall accrue on amounts actually advanced.

       THE  OBLIGATIONS  OF THE COMPANY  CONTAINED IN THIS NOTE ARE SECURED BY A
BORROWER SECURITY  AGREEMENT BETWEEN THE COMPANY AND THE HOLDER DATED AS OF JUNE
5,  1997,  AS MAY  BE  AMENDED  OR  MODIFIED  (THE  "SECURITY  AGREEMENT").  THE
OBLIGATIONS  OF THE COMPANY  CONTAINED  IN THIS NOTE ARE FURTHER  SUBJECT TO THE
TERMS OF A SUBSIDIARY SECURITY AGREEMENT BETWEEN THE SUBSIDIARIES OF THE COMPANY
AND THE HOLDER DATED AS OF JUNE 5, 1997, AS MAY






BE AMENDED OR MODIFIED (THE "SUBSIDIARY SECURITY  AGREEMENT"),  AND A SUBSIDIARY
GUARANTY BY EACH OF THE SUBSIDIARIES OF THE COMPANY IN FAVOR OF THE HOLDER DATED
AS OF JUNE 5, 1997, AS MAY BE AMENDED OR MODIFIED (THE "SUBSIDIARY GUARANTY").


                                    ARTICLE I

                                   DEFINITIONS

       1.1  Definitions.  For all  purposes  of this Note,  except as  otherwise
expressly  provided  or unless the  context  otherwise  requires:  (a) the terms
defined in this Article  have the meanings  assigned to them in this Article and
include  the  plural  as well as the  singular;  (b) all  accounting  terms  not
otherwise  defined herein have the meanings  assigned to them in accordance with
generally accepted accounting principles as promulgated from time to time by the
Association  of  Independent  Certified  Public  Accountants;  and (c) the words
"herein,"  "hereof" and  "hereunder"  and other words of similar import refer to
this  Note as a whole  and  not to any  particular  Article,  Section  or  other
subdivision.

       "Advance" means a disbursement of proceeds of this Note.

       "Board of  Directors"  means the board of  directors  of the  Company  as
elected from time to time or any duly authorized committee of that board.

       "Bridge Loan Note" means the $3,000,000 10% Bridge Loan  Promissory  Note
of the Company to Holder dated as of June 5, 1997, as may be amended,  modified,
substituted or replaced.

       "Business Day" means each Monday, Tuesday, Wednesday, Thursday and Friday
which  is  not a day  on  which  banking  institutions  in  Houston,  Texas  are
authorized or obligated by law or executive order to be closed.

       "Common Stock" means shares of common stock, par value $0.0005 per share,
of the Company.

       "Conversion  Price" means the price per share  determined  in  accordance
with Articles IV and V (as adjusted in  accordance  with the terms of this Note)
at which shares of Common Stock shall be delivered to Holder upon  conversion of
this Note.

       "Default"  means any event  which is, or after  notice or passage of time
would be, an Event of Default.

       "Event of Default" has the meaning specified in Section 3.1.

                                      -2-






       "Indebtedness"  of any  Person  means all  indebtedness  of such  Person,
whether  outstanding  on the date of this Note or hereafter  created,  incurred,
assumed  or  guaranteed,  (a) for the  principal  of and  premium,  if any,  and
interest on all debts of the Person whether outstanding on the date of this Note
or  thereafter  created  (i)  for  money  borrowed  by  such  Person  (including
capitalized  lease  obligations),  (ii) for money borrowed by others  (including
capitalized lease obligations) and guaranteed,  directly or indirectly,  by such
Person,  or (iii)  constituting  purchase money  indebtedness,  or  indebtedness
secured by  property  at the time of the  acquisition  of such  property by such
Person, for the payment of which the Person is directly or contingently  liable;
(b) for all  accrued  obligations  of the  Person in  respect  of any  contract,
agreement  or  instrument  imposing  an  obligation  upon the Person to pay over
funds;  (c)  for  all  trade  debt of the  Person;  and  (d) for all  deferrals,
renewals,  extensions  and  refundings  of, and  amendments,  modifications  and
supplements to, any of the indebtedness referred to in (a), (b) or (c) above.

       "Maturity Date", when used with respect to this Note, means July 23, 1999
(or such earlier date upon which this Note becomes due and payable under Section
3.2).

       "Note"  means  this  $10,000,000  8%  Convertible   Promissory  Note,  as
hereafter amended, modified, substituted or replaced.

       "Original   Convertible   Notes"  means  the  $2,000,000  9%  Convertible
Promissory  Note of the Company in favor of the Holder dated as of June 5, 1997,
as may be amended,  modified,  substituted  or replaced  and the  $2,900,000  7%
Convertible  Promissory  Note of the Company in favor of the Holder  dated as of
October 10, 1997, as may be amended, modified, substituted or replaced.

       "Person" means any individual,  corporation,  limited liability  company,
partnership,  joint venture,  association,  joint-stock company,  trust, estate,
other  entity,  unincorporated  organization  or  government  or any  agency  or
political subdivision thereof.

       "Subsidiary"  means a  corporation  or other  entity more than 50% of the
outstanding  voting stock of which,  or more than 50% of the equity  interest in
which, is owned, directly or indirectly,  by the Company or by one or more other
Subsidiaries  of the Company,  or by any  combination  of the Company and one or
more other  Subsidiaries,  provided,  however,  that the following  shall not be
deemed  Subsidiaries  for purposes of this Note:  Black  Warrior  International,
Inc.; Black Warrior  International  (Bermuda),  Ltd.; Black Warrior Oil and Gas,
Inc.;   and   Black   Warrior   Syria,   Ltd.   (collectively,   the   "Inactive
Organizations").  However,  if any Inactive  Organization  begins to conduct any
business (other than activities to "wind down" such organization), such Inactive
Organization  shall be considered a Subsidiary  under this  Agreement  from that
point forward. For purposes of this definition, "voting stock" means stock which
ordinarily has voting power for the election of directors,  whether at all times
or only so long as no senior  class of stock has such voting  power by reason of
any contingency.

                                   ARTICLE II

                                      -3-



                                    PAYMENTS

       2.1  Interest.  From the date of this Note  through  the  Maturity  Date,
interest shall accrue hereunder on the unpaid outstanding  principal sum of this
Note at a rate equal to eight percent (8%) per annum  calculated on the basis of
a 360-day  year.  All past due  amounts of  principal  and  interest  shall bear
interest at fifteen percent (15%) per annum calculated on the basis of a 360-day
year until paid.

       2.2 Payment of Principal and Interest.  Accrued and unpaid interest under
this Note shall be due and payable on January 23, 1999.  The  principal  and all
remaining  accrued and unpaid  interest under this Note shall be due and payable
in full on the Maturity  Date. At any time, the Holder may, at its option and in
lieu of cash, elect to be paid all accrued and unpaid interest owed to Holder by
the Company in the form of Common Stock, based on a price per share equal to the
Conversion  Price (the "Price Per Share").  The amount of all accrued and unpaid
interest  on the  Maturity  Date  shall be divided by the Price Per Share into a
whole number of shares of Common Stock,  with the remainder,  if any, being paid
in cash.

       2.3 Prepayments. Subject to Holder's right to convert, at any time before
the  Maturity  Date,  the  Company  may prepay  this Note,  in whole or in part,
without  penalty or  discount,  upon five days' prior  written  notice  given to
Holder  pursuant  to Section  7.5.  All  payments  made under this Note shall be
applied  first to accrued  interest,  and the  balance,  if any,  to  principal;
provided, however, that interest shall accrue on any remaining principal balance
and shall be payable at the rate provided above.

       2.4 Manner of Payment.  Cash  payments of principal  and interest on this
Note will be made by delivery of checks to Holder at its address as set forth in
this Note or wire transfers  pursuant to instructions  from Holder.  If the date
upon which the payment of principal and interest is required to be made pursuant
to this Note occurs other than on a Business Day, then such payment of principal
and interest  shall be made on the next  occurring  Business Day following  said
payment date and shall include  interest  through said next  occurring  Business
Day.

       2.5 Security; Guaranty. This Note is secured by the collateral defined in
the Security Agreement and by the collateral defined in the Subsidiary  Security
Agreement.  This Note and the  obligations  hereunder  and  under  the  Security
Agreement  and  the  Subsidiary   Security   Agreement  are  guaranteed  by  the
Subsidiaries of the Company pursuant to the Subsidiary Guaranty.

                                   ARTICLE III

                                    REMEDIES

       3.1 Events of Default. An "Event of Default" occurs if:

                                      -4-





              (a) the Company defaults in the payment or mandatory prepayment of
       the  principal or interest on this Note, or in the payment or a mandatory
       prepayment of the principal or interest on the Original  Convertible Note
       or the Bridge Loan Note, when such principal or interest  becomes due and
       payable and such default remains uncured for a period of five days; or

              (b) the Company or any Subsidiary  defaults in the  performance of
       any covenant made by the Company,  and such default remains uncured for a
       period of 45 days in any of (i) those certain Agreements for Purchase and
       Sale dated of even date herewith,  as of October 10, 1997, and as of June
       5, 1997,  respectively,  by and  between  the  Company  and  Holder  (the
       "Purchase Agreements"), (ii) the Common Stock Purchase Warrants issued by
       the Company to Holder as of the date hereof,  as of October 10, 1997, and
       as of June 5, 1997,  respectively  (the  "Warrants");  (iii) that certain
       Registration  Rights  Agreement  dated  as of  June  5,  1997,  as may be
       thereafter  amended or  modified,  by and  between  the  Company  and the
       Holder,  pursuant  to which  the  Company  grants to the  Holder  certain
       registration  rights in respect of the shares of Common Stock that may be
       issued under the Original  Convertible Notes, this Note and upon exercise
       of the Warrants (the "Registration Rights Agreement");  (iv) the Security
       Agreement;  (v) the Original  Convertible  Notes or the Bridge Loan Note;
       (vi) the Subsidiary Security Agreement; (vii) the Subsidiary Guaranty; or
       (viii) this Note (other than a default in the  performance  of a covenant
       specifically  addressed  elsewhere in this Section 3.1);  provided that a
       default in the performance of any covenant in Sections 8(a),  8(b), 8(c),
       8(d),  8(e),  8(f),  8(h),  8(i),  8(j),  8(k), 8(l), 8(m) or 8(n) of the
       Security  Agreement  or  Section  6.1 of this  Note  shall be an Event of
       Default immediately upon occurrence; or

              (c) any  representation  or  warranty  made by the  Company or any
       Subsidiary in the Purchase  Agreements,  the Warrants,  the  Registration
       Rights Agreement,  the Original  Convertible Notes, the Bridge Loan Note,
       the Security Agreement, the Subsidiary Security Agreement, the Subsidiary
       Guaranty,  or this Note or in any certificate furnished by the Company in
       connection with the consummation of the transaction  contemplated thereby
       or  hereby,  is untrue in any  material  respect as of the date of making
       thereof and such default remains uncured for a period of 45 days; or

              (d) the Company or any Subsidiary defaults in the payment when due
       (whether by lapse of time,  by  declaration,  by call for  redemption  or
       otherwise)  of the  principal of or interest on any  Indebtedness  of the
       Company or such Subsidiary (other than the Indebtedness evidenced by this
       Note)  having an aggregate  principal  amount in excess of $100,000 or on
       any  Indebtedness  of the  Company  to any of its  stockholders  and such
       default remains uncured for a period of 45 days; or

              (e) a  court  of  competent  jurisdiction  enters  a  judgment  or
       judgments  against  the  Company or any  Subsidiary,  or any  property or
       assets  of the  Company  or any  Subsidiary,  for the  payment  of  money
       aggregating $100,000 or more in excess of


                                      -5-




       applicable  insurance  coverage  (other than the  judgment  disclosed  on
       Schedule  3.1(e) hereto) and such default remains uncured for a period of
       45 days; or

              (f) a court of competent jurisdiction enters (i) a decree or order
       for relief in respect of the Company or any  Subsidiary in an involuntary
       case or  proceeding  under any  applicable  federal or state  bankruptcy,
       insolvency, reorganization or other similar law or (ii) a decree or order
       adjudging  the  Company or any  Subsidiary  a bankrupt or  insolvent,  or
       approving   as  properly   filed  a  petition   seeking   reorganization,
       arrangement, adjustment or composition of or in respect of the Company or
       any Subsidiary under any applicable federal or state law, or appointing a
       custodian, receiver, liquidator, assignee, trustee, sequestrator or other
       similar  official of the Company or any Subsidiary or of any  substantial
       part of the  property of the Company or any  Subsidiary  or ordering  the
       winding up or liquidation of the affairs of the Company or any Subsidiary
       and any such decree or order of relief or any such other  decree or order
       remains unstayed for a period of 90 days from its date of entry; or

              (g) the Company or any  Subsidiary  commences a voluntary  case or
       proceeding under any applicable federal or state bankruptcy,  insolvency,
       reorganization or other similar law or any other case or proceeding to be
       adjudicated  a bankrupt or  insolvent,  or the Company or any  Subsidiary
       files a  petition,  answer or consent  seeking  reorganization  or relief
       under  any  applicable  federal  or  state  law,  or the  Company  or any
       Subsidiary makes an assignment for the benefit of creditors, or admits in
       writing its inability to pay its debts generally as they become due; or

              (h) any person or group  (within the  meaning of Section  13(d) of
       the Securities  Exchange Act of 1934) becomes the beneficial owner of 40%
       or  more  of the  total  voting  power  of the  Company  and  was not the
       beneficial  owner of 40% or more of the total voting power of the Company
       as of the date hereof;  provided that the foregoing shall not include any
       person  or group  who or which  acquires  the  Warrants  or shares of the
       Company's  Common Stock  issuable  upon  exercise of the Warrants or upon
       conversion of the Original  Convertible  Notes or this Note;  and further
       provided  that such  default has not been cured or waived  within  ninety
       (90) days following such change of beneficial ownership.

              (i) the Company or any Subsidiary (1) merges or consolidates  with
       or into any other Person  (unless the Company or any of its  Subsidiaries
       is the surviving or acquiring party); (2) dissolves or liquidates; or (3)
       sells all or any substantial  portion of its assets (unless the purchaser
       is a Subsidiary of the Company).

       3.2  Acceleration of Maturity.  This Note and all accrued  interest shall
automatically  become  immediately  due  and  payable  if an  Event  of  Default
described in Sections  3.1(f),  3.1(g) or 3.1(i) occurs and, this Note shall, at
the  option of the Holder in its sole  discretion,  become  immediately  due and
payable if any other Event of Default occurs, and in every such case the

                                      -6-





Holder of the Note may declare the  principal and interest on the Note to be due
and payable immediately.

                                   ARTICLE IV

                               CONVERSION OF NOTE


       Subject to and upon  compliance  with the provisions of this Article,  at
the option of Holder, all or any part of this Note may be converted at any time,
at the  principal  amount  hereof  together  with  accrued  and unpaid  interest
thereon,  into  fully  paid  and  nonassessable  shares  (calculated  as to each
conversion  to the nearest  1/100 of a share) of Common  Stock.  The  Conversion
Price shall initially be $7.00 per share.  Notwithstanding  anything else to the
contrary set forth herein,  the Holder shall have the right to convert this Note
pursuant to the terms set forth  herein at any time,  including  the 30 Business
Days following (i) the Maturity Date or (ii) any prepayment  pursuant to Section
2.3 hereof.  If Holder  elects to convert this Note after a prepayment  has been
made  pursuant to Section  2.3,  then Holder shall return all or such portion of
the funds paid to Holder as to which Holder has elected to convert.

                                    ARTICLE V

                         ADJUSTMENT OF CONVERSION PRICE

       5.1  Anti-Dilution  Provisions.  The Conversion Price shall be subject to
adjustment  from time to time as hereinafter  provided.  Upon each adjustment of
the Conversion  Price,  the holder of this Note shall  thereafter be entitled to
purchase, at the Conversion Price resulting from such adjustment,  the number of
shares of Common Stock  obtained by multiplying  the Conversion  Price in effect
immediately  prior  to such  adjustment  by the  number  of  shares  purchasable
pursuant  hereto  immediately  prior to such adjustment and dividing the product
thereof by the Conversion Price resulting from such adjustment.

       5.2 Adjustment of Conversion Price Upon Issuance of Common Stock.

              5.2.1 (A) If and whenever  after the date hereof the Company shall
       issue  or  sell  any  Common  Stock  for  no   consideration   or  for  a
       consideration  per share less than the Conversion Price then,  forthwith,
       upon such issue or sale, the  Conversion  Price shall be reduced (but not
       increased,  except as otherwise  specifically provided in Section 5.2.2),
       to the price  (calculated  to the nearest  one-ten  thousandth of a cent)
       determined  by  dividing  (x)  an  amount  equal  to the  sum of (i)  the
       aggregate number of shares of Common Stock outstanding  immediately prior
       to such issue or sale  multiplied by the then existing  Conversion  Price
       plus (ii) the  consideration  received by the Company  upon such issue or
       sale by (y) the  aggregate  number of shares of Common Stock  outstanding
       immediately after such issue or sale.

                                      -7-





              (B)  Notwithstanding  the  provisions  of  this  Section  5.2,  no
       adjustment  shall be made in the  Conversion  Price in the event that the
       Company  issues,  in one or more  transactions,  (i)  Common  Stock  upon
       exercise of any options issued to officers, directors or employees of the
       Company  pursuant to a stock option plan or an  employment,  severance or
       consulting agreement as now or hereafter in effect, in each case approved
       by the Board of Directors  (provided that the aggregate  number of shares
       of Common Stock which may be issuable,  including options issued prior to
       the date hereof, under all such employee plans and agreements shall at no
       time exceed the number of such shares of Common Stock  outstanding on the
       date hereof on a fully  diluted basis that are issuable  under  currently
       effective employee plans and agreements); (ii) Common Stock upon exercise
       of the  Original  Convertible  Notes or this  Note or any  other  warrant
       issued  pursuant to the terms of the  Purchase  Agreements;  (iii) Common
       Stock upon exercise of any stock  purchase  warrant or option (other than
       the  options  referred  to in  clause  (i)  above)  or other  convertible
       security  outstanding on the date hereof;  or (iv) Common Stock issued as
       consideration in acquisitions.  In addition,  for purposes of calculating
       any adjustment of the  Conversion  Price as provided in this Section 5.2,
       all of  the  shares  of  Common  Stock  issuable  pursuant  to any of the
       foregoing  shall be assumed to be outstanding  prior to the event causing
       such adjustment to be made.

              5.2.2 For purposes of this Section  5.2,  the  following  shall be
       applicable:

              (A)  Issuance of Rights or Options.  In case at any time after the
       date hereof the Company shall in any manner grant (whether directly or by
       assumption  in a merger or  otherwise)  any rights to subscribe for or to
       purchase,  or any options for the purchase of,  Common Stock or any stock
       or securities  convertible  into or  exchangeable  for Common Stock (such
       convertible  or  exchangeable  stock or  securities  being herein  called
       "Convertible  Securities")  (other than warrants,  options or convertible
       securities  issued as consideration for or assumed in conjunction with an
       acquisition  or to  officers,  directors,  or  employees  of the acquired
       entity in conjunction  therewith),  whether or not such rights or options
       or the right to convert or exchange any such  Convertible  Securities are
       immediately  exercisable,  and the price  per  share for which  shares of
       Common Stock are issuable  upon the exercise of such rights or options or
       upon conversion or exchange of such Convertible Securities (determined by
       dividing (i) the total  amount,  if any,  received or  receivable  by the
       Company as consideration for the granting of such rights or options, plus
       the minimum aggregate amount of additional consideration, if any, payable
       to the Company upon the exercise of such rights or options,  or plus,  in
       the case of such rights or options that relate to Convertible Securities,
       the minimum aggregate amount of additional consideration, if any, payable
       upon  the  issue  or sale of such  Convertible  Securities  and  upon the
       conversion  or  exchange  thereof,  by (ii) the total  maximum  number of
       shares of Common  Stock  issuable  upon the  exercise  of such  rights or
       options  or upon the  conversion  or  exchange  of all  such  Convertible
       Securities issuable upon the exercise of such rights or options) shall be
       less than the Conversion  Price in effect as of the date of granting such
       rights or options, then the total maximum number of shares of Common


                                      -8-



       Stock  issuable  upon the  exercise  of such  rights or  options  or upon
       conversion or exchange of all such Convertible  Securities  issuable upon
       the exercise of such rights or options shall be deemed to be  outstanding
       as of the date of the granting of such rights or options and to have been
       issued for such price per share,  with the effect on the Conversion Price
       specified in Section  5.2.1  hereof.  Except as provided in Section 5.2.2
       hereof, no further  adjustment of the Conversion Price shall be made upon
       the  actual  issuance  of  such  Common  Stock  or  of  such  Convertible
       Securities  upon  exercise  of such  rights or options or upon the actual
       issuance  of such  Common  Stock  upon  conversion  or  exchange  of such
       Convertible Securities.

              (B) Change in Option Price or Conversion  Rate. Upon the happening
       of any of the following  events,  namely,  if the purchase price provided
       for in any  right or option  referred  to in  Section  5.2.2  above,  the
       additional consideration, if any, payable upon the conversion or exchange
       of any Convertible  Securities referred to in Section 5.2.2(A) hereof, or
       the rate at which  any  Convertible  Securities  referred  to in  Section
       5.2.2(A)  hereof,  are convertible  into or exchangeable for Common Stock
       shall  change  (other than under or by reason of  provisions  designed to
       protect against dilution),  the Conversion Price then in effect hereunder
       shall  forthwith be readjusted  (increased or decreased,  as the case may
       be) to the  Conversion  Price that would have been in effect at such time
       had such rights,  options or  Convertible  Securities  still  outstanding
       provided for such changed  purchase price,  additional  consideration  or
       conversion  rate,  as the case may be,  at the  time  initially  granted,
       issued or sold. On the expiration of any such option or right referred to
       in Section  5.2.2(A)  hereof,  or on the termination of any such right to
       convert  or  exchange  any such  Convertible  Securities  referred  to in
       Section  5.2.2(A)  hereof,  the Conversion Price then in effect hereunder
       shall  forthwith be readjusted  (increased or decreased,  as the case may
       be) to the Conversion Price that would have been in effect at the time of
       such  expiration or  termination  had such right,  option or  Convertible
       Securities,   to  the  extent  outstanding   immediately  prior  to  such
       expiration or  termination,  never been granted,  issued or sold, and the
       Common  Stock  issuable  thereunder  shall  no  longer  be  deemed  to be
       outstanding.  If the  purchase  price  provided  for in Section  5.2.2(A)
       hereof or the rate at which any  Convertible  Securities  referred  to in
       Section  5.2.2(A) hereof are convertible  into or exchangeable for Common
       Stock shall be reduced at any time under or by reason of provisions  with
       respect thereto designed to protect against dilution, then in case of the
       delivery of Common Stock upon the exercise of any such right or option or
       upon  conversion  or exchange  of any such  Convertible  Securities,  the
       Conversion Price then in effect hereunder shall, if not already adjusted,
       forthwith  be  adjusted to such  amount as would have  obtained  had such
       right,  option or  Convertible  Securities  never been  issued as to such
       Common  Stock and had  adjustments  been made  upon the  issuance  of the
       Common  Stock  delivered  as  aforesaid,  but only if as a result of such
       adjustment  the  Conversion  Price  then in effect  hereunder  is thereby
       reduced.

              (C)  Consideration  for Stock. In case at any time Common Stock or
       Convertible  Securities  or any rights or options  to  purchase  any such
       Common Stock or

                                      -9-




       Convertible   Securities   shall  be  issued   or  sold  for  cash,   the
       consideration  therefor shall be deemed to be the amount  received by the
       Company  therefor.  In case at any time  any  Common  Stock,  Convertible
       Securities  or any rights or options to purchase any such Common Stock or
       Convertible  Securities shall be issued or sold for  consideration  other
       than cash,  the amount of the  consideration  other than cash received by
       the Company  shall be deemed to be the fair value of such  consideration,
       as determined  reasonably  and in good faith by the Board of Directors of
       the Company. In case at any time any Common Stock, Convertible Securities
       or any rights or  options to  purchase  any Common  Stock or  Convertible
       Securities shall be issued in connection with any merger or consolidation
       in  which  the  Company  is the  surviving  corporation,  the  amount  of
       consideration  received therefor shall be deemed to be the fair value, as
       determined  reasonably and in good faith by the Board of Directors of the
       Company,  of such portion of the assets and business of the  nonsurviving
       corporation  as such Board of Directors may determine to be  attributable
       to such Common Stock,  Convertible  Securities,  rights or options as the
       case may be. In case at any time any rights or options  to  purchase  any
       shares  of  Common  Stock or  Convertible  Securities  shall be issued in
       connection with the issuance and sale of other securities of the Company,
       together consisting of one integral transaction in which no consideration
       is  allocated  to such rights or options by the  parties,  such rights or
       options shall be deemed to have been issued without consideration.

              (D) Record  Date.  In the case the Company  shall take a record of
       the holders of its Common Stock for the purpose of entitling  them (i) to
       receive a  dividend  or other  distribution  payable  in Common  Stock or
       Convertible Securities, or (ii) to subscribe for or purchase Common Stock
       or  Convertible  Securities,  then such record date shall be deemed to be
       the date of the  issuance  or sale of the  Common  Stock  or  Convertible
       Securities  deemed  to  have  been  issued  or sold  as a  result  of the
       declaration of such dividend or the making of such other  distribution or
       the date of the granting of such right of  subscription  or purchase,  as
       the case may be.

              (E)  Treasury  Shares.  The  number  of  shares  of  Common  Stock
       outstanding  at any given time shall not include shares owned directly by
       the Company in treasury,  and the disposition of any such shares shall be
       considered  an issuance  or sale of Common  Stock for the purpose of this
       Section 5.2.

       5.3 Stock Dividends. In case the Company shall declare a dividend or make
any other  distribution upon any shares of the Company,  payable in Common Stock
or Convertible Securities,  any Common Stock or Convertible  Securities,  as the
case may be,  issuable  in payment of such  dividend  or  distribution  shall be
deemed to have been issued or sold without consideration.

       5.4 Stock Splits and Reverse Splits.  In the event that the Company shall
at any time  subdivide  its  outstanding  shares of Common  Stock into a greater
number of  shares,  the  Conversion  Price in effect  immediately  prior to such
subdivision shall be proportionately

                                      -10-





reduced  and the  number  of  Shares  into  which  this  Note  may be  converted
immediately prior to such subdivision shall be  proportionately  increased,  and
conversely,  in the event that the  outstanding  shares of Common Stock shall at
any time be combined into a smaller number of shares,  the  Conversion  Price in
effect immediately prior to such combination shall be proportionately  increased
and the number of Shares into which this Note may be converted immediately prior
to such combination shall be proportionately reduced. Except as provided in this
Section 5.4 no adjustment in the Conversion Price and no change in the number of
Shares  shall be made  under  this  Article V as a result of or by reason of any
such subdivision or combination.

       5.5  Reorganizations  and Asset Sales. If any capital  reorganization  or
reclassification  of the capital  stock of the  Company,  or any  consolidation,
merger or share  exchange  of the  Company  with  another  Person,  or the sale,
transfer  or other  disposition  of all or  substantially  all of its  assets to
another  Person  shall be  effected in such a way that  holders of Common  Stock
shall be entitled to receive capital stock, securities or assets with respect to
or in exchange for their shares, then the following provisions shall apply:

              5.5.1 As a  condition  of such  reorganization,  reclassification,
       consolidation,   merger,   share  exchange,   sale,   transfer  or  other
       disposition (except as otherwise provided below in Section 5.5.3), lawful
       and  adequate  provisions  shall be made  whereby the holder of this Note
       shall  thereafter  have the right to purchase  and receive upon the terms
       and  conditions  specified  in  this  Note  and in  lieu  of  the  shares
       immediately  theretofore  receivable  upon  the  exercise  of the  rights
       represented hereby, such shares of capital stock, securities or assets as
       may be issued or payable  with  respect to or in exchange for a number of
       outstanding  shares of such  Common  Stock  equal to the number of shares
       immediately   theretofore   so   receivable   had  such   reorganization,
       reclassification, consolidation, merger, share exchange or sale not taken
       place, and in any such case appropriate provision reasonably satisfactory
       to such holder shall be made with respect to the rights and  interests of
       such holder to the end that the  provisions  hereof  (including,  without
       limitation, provisions for adjustments of the Conversion Price and of the
       number  of shares  receivable  upon the  exercise)  shall  thereafter  be
       applicable,  as nearly as possible,  in relation to any shares of capital
       stock,  securities or assets thereafter  deliverable upon the exercise of
       this Note.

              5.5.2 In the event of a merger, share exchange or consolidation of
       the Company with or into another  Person as a result of which a number of
       shares of common stock or its equivalent of the successor  Person greater
       or  lesser  than  the  number  of  shares  of  Common  Stock  outstanding
       immediately  prior to such merger,  share exchange or  consolidation  are
       issuable to holders of Common Stock,  then the Conversion Price in effect
       immediately prior to such merger,  share exchange or consolidation  shall
       be  adjusted  in the same manner as though  there were a  subdivision  or
       combination of the outstanding shares of Common Stock.


    
                                  -11-




              5.5.3 The Company shall not effect any such consolidation, merger,
       share exchange,  sale,  transfer or other disposition  unless prior to or
       simultaneously  with the  consummation  thereof the successor  Person (if
       other than the Company) resulting from such consolidation, share exchange
       or merger or the Person  purchasing  or otherwise  acquiring  such assets
       shall have assumed by written instrument executed and mailed or delivered
       to the Holder hereof at the last address of such Holder  appearing on the
       books of the Company the obligation to deliver to such Holder such shares
       of  capital  stock,  securities  or  assets  as, in  accordance  with the
       foregoing  provisions,  such Holder may be  entitled to receive,  and all
       other liabilities and obligations of the Company hereunder.  Upon written
       request by the Holder hereof, such Successor Person will issue a new Note
       revised to reflect the  modifications  in this Note effected  pursuant to
       this Section 5.5.

              5.5.4  If a  purchase,  tender  or  exchange  offer is made to and
       accepted  by the  holders  of 50% or more of the  outstanding  shares  of
       Common  Stock,  the Company shall not effect any  consolidation,  merger,
       share  exchange  or  sale,  transfer  or  other  disposition  of  all  or
       substantially  all of the  Company's  assets with the Person  having made
       such offer or with any  affiliate  of such  Person,  unless  prior to the
       consummation  of  such  consolidation,   merger,  share  exchange,  sale,
       transfer or other  disposition  the holder hereof shall have been given a
       reasonable  opportunity  to then elect to receive upon the  conversion of
       this Note either the capital  stock,  securities  or assets then issuable
       with  respect to the Common  Stock or the capital  stock,  securities  or
       assets, or the equivalent, issued to previous holders of the Common Stock
       in accordance with such offer.

       5.6 Adjustment for Asset Distribution. If the Company declares a dividend
or other  distribution  payable  to all  holders  of shares  of Common  Stock in
evidences  of  indebtedness  of the  Company  or  other  assets  of the  Company
(including,  cash (other than  regular cash  dividends  declared by the Board of
Directors),  capital stock (other than Common Stock,  Convertible  Securities or
options or rights thereto) or other  property),  the Conversion  Price in effect
immediately  prior to such  declaration  of such dividend or other  distribution
shall  be  reduced  by an  amount  equal  to the  amount  of  such  dividend  or
distribution  payable per share of Common Stock,  in the case of a cash dividend
or distribution, or by the fair value of such dividend or distribution per share
of  Common  Stock  (as  reasonably  determined  in good  faith  by the  Board of
Directors of the Company),  in the case of any other  dividend or  distribution.
Such reduction  shall be made whenever any such dividend or distribution is made
and shall be  effective as of the date as of which a record is taken for purpose
of such dividend or  distribution  or, if a record is not taken,  the date as of
which  holders  of  record  of  Common  Stock   entitled  to  such  dividend  or
distribution are determined.

       5.7 De  Minimis  Adjustments.  No  adjustment  in the number of shares of
Common Stock  purchasable  hereunder  shall be required  unless such  adjustment
would  require an increase  or  decrease  of at least one share of Common  Stock
purchasable  upon  conversion of the Note and no  adjustment  in the  Conversion
Price shall be  required  unless such  adjustment  would  require an increase or
decrease of at least $.01 in the Conversion Price;  provided,  however, that any

                                      -12-



adjustments  which by reason of this  Section  5.7 are not  required  to be made
shall be carried  forward and taken into account in any  subsequent  adjustment.
All  calculations  shall  be made to the  nearest  full  share  or  nearest  one
hundredth of a dollar, as applicable.

       5.8 Notice of Adjustment.  Whenever the Conversion Price or the number of
Shares  issuable  upon the  conversion  of the Note shall be  adjusted as herein
provided,  or the rights of the holder  hereof  shall  change by reason of other
events specified herein, the Company shall compute the adjusted Conversion Price
and the adjusted number of Shares in accordance  with the provisions  hereof and
shall prepare an Officer's  Certificate  setting  forth the adjusted  Conversion
Price and the adjusted  number of Shares  issuable  upon the  conversion of this
Note or specifying the other shares of stock, securities or assets receivable as
a result of such change in rights,  and showing in  reasonable  detail the facts
and  calculations  upon which such  adjustments or other changes are based.  The
Company shall cause to be mailed to the Holder  hereof copies of such  Officer's
Certificate  together with a notice  stating that the  Conversion  Price and the
number of Shares purchasable upon conversion of this Note have been adjusted and
setting forth the adjusted  Conversion  Price and the adjusted  number of Shares
purchasable upon conversion of this Note.

       5.9 Notifications to Holders. In case at any time the Company proposes:

              (i) to  declare  any  dividend  upon its Common  Stock  payable in
       capital stock or make any special dividend or other  distribution  (other
       than cash dividends) to the holders of its Common Stock;

              (ii) to offer for  subscription  pro rata to all of the holders of
       its Common Stock any  additional  shares of capital stock of any class or
       other rights;

              (iii) to effect any capital reorganization, or reclassification of
       the  capital  stock of the  Company,  or  consolidation,  merger or share
       exchange of the Company with another Person,  or sale,  transfer or other
       disposition of all or substantially all of its assets; or

              (iv) to effect a voluntary or involuntary dissolution, liquidation
       or winding up of the Company,

then, in any one or more of such cases, the Company shall give the holder hereof
(a) at least 10 days (but not more  than 90 days)  prior  written  notice of the
date on which the books of the Company  shall  close or a record  shall be taken
for such dividend, distribution or subscription rights or for determining rights
to vote in  respect  of any  such  issuance,  reorganization,  reclassification,
consolidation, merger, share exchange, sale, transfer, disposition, dissolution,
liquidation  or  winding  up,  and  (b)  in  the  case  of  any  such  issuance,
reorganization,  reclassification,  consolidation, merger, share exchange, sale,
transfer, disposition,  dissolution, liquidation or winding up, at least 10 days
(but not more than 90 days) prior written notice of the

                                      -13-





date  when the same  shall  take  place.  Such  notice  in  accordance  with the
foregoing  clause  (a) shall  also  specify,  in the case of any such  dividend,
distribution  or  subscription  rights,  the date on which the holders of Common
Stock  shall  be  entitled  thereto,  and such  notice  in  accordance  with the
foregoing  clause (b) shall also specify the date on which the holders of Common
Stock shall be entitled to exchange their Common Stock,  as the case may be, for
securities   or   other   property   deliverable   upon   such   reorganization,
reclassification,   consolidation,   merger,  share  exchange,  sale,  transfer,
disposition, dissolution, liquidation or winding up, as the case may be.

       5.10 Company to Prevent Dilution.  If any event or condition occurs as to
which  other  provisions  of this  Article  are not  strictly  applicable  or if
strictly  applicable would not fairly protect the exercise or purchase rights of
this  Note  evidenced  hereby  in  accordance  with  the  essential  intent  and
principles of such provisions, or that might materially and adversely affect the
exercise or purchase  rights of the holder  hereof under any  provisions of this
Note,  then the Company shall make such  adjustments in the  application of such
provisions,  in accordance with such essential  intent and principles,  so as to
protect such  exercise and purchase  rights as  aforesaid,  and any  adjustments
necessary  with  respect  to the  Conversion  Price  and the  number  of  shares
purchasable  hereunder so as to preserve the rights of the holder hereunder.  In
no event shall any such  adjustment have the effect of increasing the Conversion
Price as otherwise  determined pursuant to this Article except in the event of a
combination of shares of the type  contemplated in Section 5.4 hereof,  and then
in no event to an amount greater than the Conversion Price as adjusted  pursuant
to Section 5.4 hereof.

                                   ARTICLE VI

                                    COVENANTS

       The  Company  covenants  and  agrees  that,  so  long  as  this  Note  is
outstanding:

       6.1 Payment of Principal and Accrued Interest.  The Company will duly and
punctually pay or cause to be paid the principal sum of this Note, together with
interest  accrued  thereon  from the date  hereof  to the  date of  payment,  in
accordance with the terms hereof.

       6.2 Corporate Existence. The Company will, and will cause each Subsidiary
to, do or cause to be done all things  necessary  to  preserve  and keep in full
force and effect its corporate  existence,  rights  (charter and  statutory) and
franchises;  provided,  however,  that the Company or a Subsidiary  shall not be
required  to  preserve  any such  right  or  franchise  if it  shall  reasonably
determine that the preservation thereof is no longer desirable in the conduct of
its business.

       6.3 Taxes;  Claims; etc. The Company will, and will cause each Subsidiary
to, promptly pay and discharge all lawful taxes,  assessments,  and governmental
charges or levies imposed upon it or upon its income or profits,  or upon any of
its  properties,  real,  personal,  or mixed,  before the same  shall  become in
default,  as well as all lawful  claims for labor,  materials,  and  supplies or
otherwise which, if unpaid, might become a lien or charge upon such properties

                                      -14-




or any part  thereof,  and which  lien or charge  will have a  material  adverse
effect on the  business of the  Company;  provided,  however,  that  neither the
Company nor any Subsidiary shall be required to pay or cause to be paid any such
tax,  assessment,  charge,  levy, or claim prior to  institution  of foreclosure
proceedings  if the validity  thereof  shall  concurrently  be contested in good
faith by  appropriate  proceedings  and if the  Company  shall have  established
reserves  deemed by the Company  adequate with respect to such tax,  assessment,
charge, levy, or claim.

       6.4 Maintenance of Existence and  Properties.  The Company will, and will
cause each Subsidiary to, keep its material  properties in good repair,  working
order,  and  condition,  ordinary wear and tear  excepted,  so that the business
carried on may be properly  conducted  at all times in  accordance  with prudent
business management.

       6.5 SEC Reports.  The Company  will deliver to the Holder  within 20 days
after it files them with the SEC, copies of its annual and quarterly reports and
of the information,  documents, and other reports (or copies of such portions of
any of the foregoing as the SEC may by rules and  regulations  prescribe)  which
the Company is required or elects to file with the SEC pursuant to Section 13 or
15(d) of the  Securities  Exchange Act of 1934.  The Company will timely  comply
with  its  reporting  and  filing   obligations  under  the  applicable  federal
securities laws.

       6.6 Notice of Defaults.  The Company will  promptly  notify the Holder in
writing of the  occurrence of (i) any Event of Default under this Note, and (ii)
any event of default (or if any event of default  would  result upon any payment
with  respect to this Note) with  respect to any  Indebtedness  as such event of
default is defined  therein or in the instrument  under which it is outstanding,
permitting holders to accelerate the maturity of such Indebtedness.

       6.7 Compliance with Laws. The Company will promptly comply with all laws,
ordinances and  governmental  rules and regulations to which it is subject,  the
violation of which would materially and adversely affect the Company.

       6.8  Amendments  to  Charter.  The  Company  will not amend or modify its
charter without the prior written consent of Holder.

       6.9 Mergers  and  Acquisitions.  Without  the consent of the Holder,  the
Company or any Subsidiary will not dissolve,  liquidate,  consolidate,  merge or
enter  into a share  exchange  with or sell  or  transfer  all or a  substantial
portion of its assets to any Person.

         6.10  Election of  Director.  The Company  will use its best efforts to
cause the  election,  at all  shareholders'  meetings  called for the purpose of
electing  directors  of the Company or in any other  action  taken to elect such
directors,  of one person  designated  by Holder as a nominee  (the  "Designated
Director"). If a vacant directorship arises due to the resignation or disability
of the Designated  Director,  or if the  Designated  Director is removed for any
reason,  the  Company  will use its best  efforts  to cause the  appointment  of
another person designated by Holder to replace the Designated Director.

                                      -15-




                                   ARTICLE VII

                                  MISCELLANEOUS

       7.1 Consent to Amendments.  This Note may be amended, and the Company may
take any action herein prohibited, or omit to perform any act herein required to
be performed by it, if and only if the Company shall obtain the written  consent
to such  amendment,  action or omission to act from the holders of a majority of
the aggregate principal amount of this Note.

       7.2  Benefits  of Note;  No  Impairment  of  Rights  of  Holder of Senior
Indebtedness.  Nothing  in this  Note,  express  or  implied,  shall give to any
Person, other than the Company,  Holder, and their successors any benefit or any
legal or equitable right, remedy or claim under or in respect of this Note.

       7.3  Successors  and Assigns.  All covenants and  agreements in this Note
contained  by or on behalf of the Company and the Holder shall bind and inure to
the  benefit of the  respective  successors  and  assigns of the Company and the
Holder.

       7.4 Restrictions on Transfer.  Holder shall not transfer this Note except
(by the grant of a  security  interest)  to its  lender or  lenders.  As between
Holder and its lender or lenders,  this Note is  transferable in the same manner
and with the same effect as in the case of a negotiable  instrument payable to a
specified person.  Any lender to which Holder grants a security interest in this
Note shall be  entitled  to  exercise  all  remedies  to which it is entitled by
contract or by law, including (without  limitation)  transferring this Note into
its own  name or into  the  name of any  purchaser  at any  sale  undertaken  in
connection with enforcement by such lender of its remedies.

       7.5  Notice;  Address  of  Parties.  Except as  otherwise  provided,  all
communications to the Company or Holder provided for herein or with reference to
this Note  shall be deemed to have  been  sufficiently  given or served  for all
purposes on the third  business day after being sent as certified or  registered
mail,  postage  and  charges  prepaid,  to the  following  addresses:  if to the
Company:  Black  Warrior  Wireline  Corp.,  3748  Highway  #45 North,  Columbus,
Mississippi  39701, or at any other address designated by the Company in writing
to Holder; if to Holder:  St. James Capital Partners,  L.P., _ St. James Capital
Corp., 1980 Post Oak Boulevard,  Suite 2030, Houston, Texas 77056, Attn: John L.
Thompson,  or at any  other  address  designated  by Holder  to the  Company  in
writing.

       7.6  Separability  Clause.  In case any  provision  in this Note shall be
invalid,  illegal or unenforceable in any jurisdiction,  the validity,  legality
and enforceability of the remaining provisions in such jurisdiction shall not in
any way be affected or impaired thereby;  provided,  however,  such construction
does not destroy the essence of the bargain provided for hereunder.

       7.7  Governing  Law.  This Note shall be governed  by, and  construed  in
accordance


                                      -16-




with, the internal laws of the State of Delaware  (without  regard to principles
of choice of law).

       7.8 Usury. It is the intention of the parties hereto to conform  strictly
to the  applicable  laws of the  State of  Delaware  and the  United  States  of
America,  and  judicial  or  administrative  interpretations  or  determinations
thereof  regarding the contracting  for,  charging and receiving of interest for
the use,  forbearance,  and detention of money (hereinafter  referred to in this
Section 7.8 as "Applicable  Law").  The Holder shall have no right to claim,  to
charge or to receive any interest in excess of the maximum rate of interest,  if
any,  permitted  to be  charged  on  that  portion  of the  amount  representing
principal  which is outstanding  and unpaid from time to time by Applicable Law.
Determination  of the rate of interest  for the purpose of  determining  whether
this  Note is  usurious  under  Applicable  Law  shall  be  made by  amortizing,
prorating,  allocating  and  spreading  in equal parts  during the period of the
actual  time of this Note,  all  interest  or other sums  deemed to be  interest
(hereinafter  referred  to in  this  Section  7.8 as  "Interest")  at  any  time
contracted  for,  charged or received from the Company in  connection  with this
Note. Any Interest  contracted for, charged or received in excess of the maximum
rate allowed by Applicable Law shall be deemed a result of a mathematical  error
and a mistake.  If this Note is paid in part prior to the end of the full stated
term of this Note and the Interest  received for the actual  period of existence
of this Note exceeds the maximum rate allowed by  Applicable  Law,  Holder shall
credit the amount of the excess  against any amount owing under this Note or, if
this Note has been paid in full,  or in the event  that it has been  accelerated
prior to maturity, Holder shall refund to the Company the amount of such excess,
and shall not be subject to any of the penalties  provided by Applicable Law for
contracting  for,  charging or receiving  Interest in excess of the maximum rate
allowed by Applicable Law. Any such excess which is unpaid shall be canceled.

                                      -17-





       IN WITNESS  WHEREOF,  the Company has caused this  instrument  to be duly
executed on the date first above written.

                                             BLACK WARRIOR WIRELINE CORP.



                                             By:
                                                   William L. Jenkins, President



















                      [Signature Page -- Convertible Note]


                                      -18-