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                                                                   EXHIBIT 3.9.1

                          CERTIFICATE OF INCORPORATION
                                        
                                       OF
                                        
                                 C.& W.A., INC.
                                        
                                   * * * * *


          1.   The name of the corporation is

                   C.& W.A., INC.

          2.   The address of its registered office in the State of Delaware is 
No. 100 West Tenth Street, in the City of Wilmington, County of New Castle. The
name of its registered agent at such address is The Corporation Trust Company.

          3.   The nature of the business or purposes to be conducted or
promoted is:

          To engage in any lawful act or activity for which corporations may be
organized under the General Corporation Law of Delaware.

          4.   The total number of shares of stock which the corporation shall
have authority to issue is one thousand (1,000) and the par value of each of
such shares is One Dollar ($1.00) amounting in the aggregate to One Thousand
Dollars ($1,000.00).                   

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          5.   The name and mailing address of each incorporator is as follows:


          NAME                    MAILING ADDRESS
          ----                    ---------------

                              100 West Tenth Street
B. J. Consono                 Wilmington, Delaware 19899

                              100 West Tenth Street
F. J. Obara, Jr.              Wilmington, Delaware 19899


J. L. Rivera                  100 West Tenth Street
                              Wilmington, Delaware 19899

          6.   The corporation is to have perpetual existence.

          7.   In furtherance and not in limitation of the powers conferred by
statute, the board of directors is expressly authorized.

          To make, alter or repeal the by-laws of the corporation.

          To authorize and cause to be executed mortgages and liens upon the
real and personal property of the corporation.

          To set apart out of any of the funds of the corporation available for
dividends a reserve or reserves for any proper purpose and to abolish any such
reserve in the manner in which it was created.

          By a majority of the whole board, to designate one or more committees,
each committee to consist of one or more of the directors of the corporation.
The board may designate one or more directors as alternate members of any
committee, who may replace any absent or disqualified member at any meeting of
the committee. The by-laws may provide that in the absence or disqualification
of a member of a committee, the member or members thereof present at any meeting
and not disqualified from voting, whether or



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not he or they constitute a quorum, may unanimously appoint another member of
the board of directors to act at the meeting in the place of any such absent or
disqualified member. Any such committee, to the extent provided in the
resolution of the board of directors, or in the by-laws of the corporation,
shall have and may exercise all the powers and authority of the board of
directors in the management of the business and affairs of the corporation, and
may authorize the seal of the corporation to be affixed to all papers which may
require it; but no such committee shall have the power or authority in
reference to amending the certificate of incorporation, adopting an agreement
of merger or consolidation, recommending to the stockholders the sale, lease or
exchange of all or substantially all of the corporation's property and assets,
recommending to the stockholders a dissolution of the corporation or a
revocation of a dissolution, or amending the by-laws of the corporation; and,
unless the resolution or by-laws, expressly so provide, no such committee shall
have the power or authority to declare a dividend or to authorize the issuance
of stock.

          When and as authorized by the stockholders in accordance with
statute, to sell, lease or exchange all or substantially all of the property
and assets of the corporation, including its good will and its corporate
franchises, upon such terms and conditions and for such consideration, which may
consist in whole or in part of money or property including shares of stock in,
and/or other securities of, any other corporation or corporations, as its
board of directors shall deem expedient and for the best interests of the
corporation.


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          8.   Meetings of stockholders may be held within or without the Sate
of Delaware, as the by-laws may provide. The books of the corporation may be
kept (subject to any provision contained in the statutes) outside the State of
Delaware at such place or places as may be designated from time to time by the
board of directors or in the by-laws of the corporation. Elections of
directors need not be by written ballot unless the by-laws of the corporation
shall so provide.

          9.   The corporation reserves the right to amend, alter, change or
repeal any provision contained in this certificate of incorporation, in the
manner now or hereafter prescribed by statute, and all rights conferred upon
stockholders herein are granted subject to this reservation.

          WE, THE UNDERSIGNED, being each of the incorporators hereinbefore
named, for the purpose of forming a corporation pursuant to the General
Corporation Law of the State of Delaware, do make this certificate, hereby
declaring and certifying that this is our act and deed and the facts herein
stated are true, and accordingly have hereunto set our hands this 11th day of
September 1970.


                                             /s/ B J. CONSONO
                                             ----------------------


                                             /s/ F. J. OBARA, JR.
                                             ----------------------



                                             /s/ J. L. RIVERA
                                             ----------------------
 


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STATE OF DELAWARE        )
                         )  ss:
COUNTY OF NEW CASTLE     )



          BE IT REMEMBERED that on this 11th day of September 1979,
personally came before me, a Notary Public for the State of Delaware, B. J.
Consono, F. J. Obara, Jr. and J. L. Rivera, all of the parties to the foregoing
certificate of incorporation, known to me personally to be such, and severally
acknowledged the said certificate to be the act and deed of the signers
respectively and that the facts stated therein are true.

          GIVEN under my hand and seal of office the day and year aforesaid.





                                                     /s/ [ILLEGIBLE] 
                                                     ---------------------------
                                                                   Notary Public