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Exhibit 4.2    
    


[Union
Electric Company Letterhead] 


Company Order


July 28,
2003 


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 $200,000,000 aggregate principal amount of the Company's 5.10% Senior
Secured Notes due 2018 (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. 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 DD" (the "First Mortgage Bonds") in the
principal amount of $200,000,000 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 Goldman, Sachs & Co. and Wachovia Capital Markets, LLC, on behalf of the several underwriters, 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, July 28, 2003, at the offices of Pillsbury Winthrop LLP, One Battery Park Plaza, New York, NY 10004. 








        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/  BELINDA BROWN      
 Name: Belinda Brown

As Agent











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Exhibit 4.2