EXHIBIT 10.15




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August 28, 1995



Mr. David J. Birkenshaw
Chairman of the Board and Chief Executive Officer
Atlas Corporation
Republic Plaza
370 Seventeenth Street
Suite 3150
Denver, Colorado 80202

Dear Mr. Birkenshaw:

     It is proposed that certain revisions be made to the Employment Agreement
(the "Agreement") made as of September 22, 1993 between yourself and Atlas
Corporation (the "Company") in order to reflect the increase in the time which
you must devote to your duties thereunder, to increase your base annual salary
to $200,000, to conform the Agreement, where appropriate, to the terms of the
Long Term Incentive Plan of the Company, to broaden the definition of "Good
Reason" in Section 6.1(g) of the Agreement and to provide for look-back
provisions with regard to Section 6.2 of the Agreement.  Such revisions shall be
as follows:

     1.   Section 2 shall be revised to define the time which Executive must
devote to his duties thereunder as "(i.e., 100% of Executive's business time)."
                                     ----                                      

     2.   Section 3 shall be revised to read as follows:

          Salary.  As compensation for the services to be furnished by Executive
          ------                                                                
to Employer hereunder, as long as Executive is employed by Employer hereunder,
Employer shall pay Executive a salary at a minimum annual rate of $200,000
payable in accordance with Employer's standard payroll policies applicable to
officers.

     3.   Section 6.1(c) shall be revised to read as follows (the underlined
language, other than the defined term, is added):

          "Change of Control Event" means any one of the following:  (i)
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     Continuing Directors no longer constitute at least two thirds of the
     Directors constituting the Board; (ii) any person or group (as defined in
     Rule 13d-5 under 

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     the Securities Exchange Act of 1934), together with its affiliates, other
                                                                         -----
     than Phoenix Financial Holdings Inc., Mackenzie Financial Corporation or
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     M.I.M. Holdings Limited (in each case, together with its affiliates),
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     becomes the beneficial owner, directly or indirectly, of 15% or more of
     Employer's then outstanding Common Stock or 15% or more of the voting power
     of Employer's then outstanding securities entitled generally to vote for
     the election of Directors, provided that the foregoing circumstances shall
     not constitute a Change of Control Event if such beneficial owner is
     Employer, any subsidiary of Employer, any employee benefit plan or employee
     stock plan of Employer or of any subsidiary of Employer, and provided
                                                              ------------
     further that, notwithstanding the foregoing, a Change of Control Event
     ----------------------------------------------------------------------
     shall be deemed to occur if Mackenzie Financial Corporation, and its
     --------------------------------------------------------------------
     affiliates, or M.I.M. Holdings Limited, and its affiliates, shall acquire
     -------------------------------------------------------------------------
     25% or more of the Employer's then outstanding Common Stock or the voting
     -------------------------------------------------------------------------
     power of the Employer's then outstanding securities entitled generally to
     -------------------------------------------------------------------------
     vote for the election of Directors; (iii) the approval by Employer's
     ----------------------------------
     stockholders of the merger or consolidation of Employer with any other
     corporation, the sale of substantially all of Employer's assets or the
     liquidation or dissolution of Employer, unless, in the case of a merger or
     consolidation, the Continuing Directors in office immediately prior to such
     merger or consolidation constitute at least two thirds of the directors
     constituting the board of directors of the surviving corporation of such
     merger or consolidation and any parent (as such term is defined in Rule 
     12b-2 under the Securities Exchange Act of 1934) of such corporation; or
     (iv) at least two thirds of the Continuing Directors in office immediately
     prior to any other action taken or proposed to be taken by Employer's
     stockholders or by the Board determines that such action constitutes, or
     that such proposed action, if taken, would constitute, a Change of Control
     of Employer and such action is taken.

     4.   Section 6.1(g)(i)(A) shall be revised to read as follows:

       (1) the assignment to Executive of any duties and responsibilities, or
     any limitation of Executive's duties and responsibilities, inconsistent
     with Executive's positions, duties, responsibilities and status as an
     executive of Employer or (2) any removal of Executive from, or any failure
     to reelect Executive to, any of Executive's positions with Employer except
     for Cause or as a result of the death or Disability of Executive ...

     5.   Section 6.2(b)(i) shall be revised to add the following underlined
language:

          Executive shall be entitled to compensation as specified in Section
     6.2(b)(ii) and (iii) if (A) Employer terminates Executive's employment
     hereunder without Cause either prior to 3 months before a Change of Control
                                   ------------------                           
     Event or more than two years after the last Change of Control Event, or (B)
     Executive voluntarily terminates his employment hereunder with Good Reason
     either prior to 3 months before a Change of Control Event or more than two
            -----------------                                                  
     years after the last Change of Control Event.

     6.   Section 6.2(c)(i) shall be revised to add the following underlined
language:

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          Executive shall be entitled to compensation as specified in Section
     6.2(c)(ii) and (iii) if (A) Employer terminates Executive's employment
     hereunder without Cause either (1) within 3 months prior to a Change of
                             -----------------------------------------------
     Control Event or (2) upon or after a Change of Control Event but within two
     --------------------                                                       
     years after the date of that Change of Control Event, or (B) Executive
     voluntarily terminates his employment hereunder with Good Reason either (1)
                                                                      ----------
     within 3 months prior to a Change of Control Event or (2) upon or after a
     ---------------------------------------------------------                
     Change of Control Event but within two years after the date of that Change
     of Control Event.

     Please sign and date this letter in the space indicated below in order to
affirm your acceptance of and agreement to the proposed revisions to the
Agreement, as above set forth.

                                    Very truly yours,

                                    ATLAS CORPORATION

                                    _________________________________
                                    [Name]
                                    [Title]



Accepted and agreed to this _____ day of ________, 1995:



By:       /s/    David J. Birkenshaw
      --------------------------------------------
         David J. Birkenshaw


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