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Exhibit 4.2    
    


        [Union Electric Company Letterhead] 


Company
Order 


September 23,
2004 


The
Bank of New York

101 Barclay Street

Floor 21W

New York, New York 10286 


Ladies
and Gentlemen: 


        Application
is hereby made to The Bank of New York, a New York banking corporation, as trustee (the "Trustee"), under the Indenture dated as of August 15, 2002 (the "Indenture"),
between Union Electric Company, a Missouri corporation (the "Company"), and the Trustee for the authentication and delivery of $300,000,000 aggregate principal amount of the Company's 5.10% Senior
Secured Notes due 2019 (the "Notes"), pursuant to the provisions of Article II of the Indenture. On or after the Release Date, the Company, in its discretion, may change the descriptive title
of the Notes to delete the word "Secured" from such descriptive title. Additional Notes without limitation as to amount, and without the consent of the holders of the then Outstanding Notes, may also
be authenticated and delivered in the manner provided in Section 2.05 of the Indenture. All capitalized terms not defined herein which are defined in the Indenture shall have the same meaning
as used in the Indenture. 


        In
connection with this Company Order, there are delivered to you herewith the following: 



	1.
	Certified
copies of the resolutions adopted by the Board of Directors of the Company authorizing this Company Order and the issuance and sale of the Notes by the Company pursuant to
Section 2.05(c)(1) of the Indenture;



	2.
	Opinions
of Counsel addressed to you or in which it is stated that you may rely pursuant to Section 2.05(c)(2) of the Indenture;



	3.
	Expert's
certificate pursuant to Section 2.05(c)(3) of the Indenture;



	4.
	Officers'
Certificate pursuant to Section 2.05(c)(4) of the Indenture;



	5.
	A
Global Note representing the Notes and, pursuant to Section 2.05(c) of the Indenture, specifying the terms of the Notes (which terms are incorporated by reference herein)
executed on behalf of the Company in accordance with the terms of Section 2.05(a) of the Indenture; and



	6.
	Pursuant
to Section 2.05(c)(3) of the Indenture, the Company's First Mortgage Bonds designated "First Mortgage Bonds, Senior Notes Series GG" (the "First Mortgage Bonds") in the
principal amount of $300,000,000 relating to the Notes, fully registered in the name of the Trustee in trust for the benefit of the Holders from time to time of such Notes. 




        You
are hereby instructed to authenticate the Global Note representing the Notes and deliver it to The Depository Trust Company ("DTC") or its custodian. The Global Note representing the
Notes is to be held for delivery to BNP Paribas Securities Corp., BNY Capital Markets, Inc. and Lehman Brothers Inc., against payment therefor at the closing in respect of the sale
thereof, such closing to be held at 10:00 a.m., New York time, September 23, 2004, at the offices of Pillsbury Winthrop LLP, 1540 Broadway, New York, NY 10036. 










        Please
acknowledge receipt of the Global Note representing the Notes, the instructions referred to above and the supporting documentation pursuant to the Indenture referred to above. 



	

 	
 	

Very truly yours,

Union Electric Company

(d/b/a AmerenUE)
	

 	
 	

By:	

/s/  JERRE E. BIRDSONG      
 Name: Jerre E. Birdsong

Title: Vice President and Treasurer





        Receipt
from the Company of the Global Note representing the Notes, certain instructions related thereto and the supporting documentation pursuant to the Indenture, including the First
Mortgage Bonds in trust for the benefit of the Holders in connection with the authentication and delivery of the Notes is hereby acknowledged. 



	 	 	The Bank of New York,

as Trustee
	

 	
 	

By:	

/s/  ROBERT J. DUNN      
 Name: Robert J. Dunn

                As Agent













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Exhibit 4.2