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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 18)*
NAME OF ISSUER: PITT-DES MOINES, INC.
TITLE OF CLASS OF SECURITIES: Common Stock, No Par Value
CUSIP NUMBER: 724508-106
Check the following box if a fee is being paid with this statement: [ ]
* The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which
would alter the disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not be
deemed to be "filed" for the purpose of Section 18 of the Securities
Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of
that section of the Act but shall be subject to all other provisions of the
Act (however, see the Notes).
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CUSIP NO. 724508-106 SCHEDULE 13G PAGE 2 OF 5
1) Name of Reporting Person W. R. Jackson
SS or IRS Identification No.
of Above Person ###-##-####
2) Check the Appropriate Box (a) _________________
if a Member of a Group
(See Instructions) (b) X
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3) SEC Use Only
4) Citizenship or Place of Organization: United States
Number of Shares
Beneficially Owned by Each
Reporting Person With (5) Sole Voting Power
220,512
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(6) Shared Voting Power
122,765
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(7) Sole Dispositive Power
220,512
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(8) Shared Dispositive Power
122,765
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9) Aggregate Amount Beneficially
Owned by Each Reporting Person 343,277
10) Check if the Aggregate Amount
in Row (9) Excludes Certain
Shares (See Instructions)
11) Percent of Class Represented
by Amount in Row (9) 9.8%
12) Type of Reporting Person IN
(See Instructions)
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CUSIP NO. 724508-106 SCHEDULE 13G PAGE 3 OF 5
Item 1.
(a) Name of Issuer: PITT-DES MOINES, INC.
(b) Address of Issuer's Principal Executive Offices:
3400 Grand Avenue
Pittsburgh, PA 15225
Item 2.
(a) Name of Person Filing: W. R. Jackson
(b) Address of Principal Business Office, or if None, Residence:
3400 Grand Avenue
Pittsburgh, PA 15225
(c) Citizenship: United States
(d) Title of Class of Securities:
Common Stock, No Par Value
(e) CUSIP Number: 724508-106
Item 3. If this statement if filed pursuant to Rules 13d-1(b), or 13d-2(b),
check whether the person filing is a:
(a) [ ] Broker or Dealer registered Under Section 15 of the Act.
(b) [ ] Bank as defined in Section 3(a)(6) of the Act
(c) [ ] Insurance Company as defined in Section 3(a)(19) of the Act.
(d) [ ] Investment Company registered under Section 8 of the Investment
Company Act.
(e) [ ] Investment Advisor registered under Section 203 of the Investment
Advisers Act of 1940.
(f) [ ] Employee Benefit Plan, Pension Fund which is subject to the provisions
of the Employee Retirement Income Security Act of 1974 or Endowment
Fund; see 240.13d-1 (b)(1)(ii)(F).
(g) [ ] Parent Holding Company, in accordance with 240.13-(d)(1)(b)(ii)(G).
(Note: See Item 7)
(h) [ ] Group, in accordance with 240.13d-1(b)(1)(ii)(H).
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CUSIP NO. 724508-106 SCHEDULE 13G PAGE 4 OF 5
Item 4. Ownership:
(a) Amount beneficially owned: 343,277
(b) Percent of Class: 9.8%
(c) Number of shares as to which person has:
(i) Sole power to vote
or to direct the vote: 220,512
(ii) Shared power to vote
or to direct the vote: 122,765
(iii) Sole power to dispose
or to direct the
disposition of shares: 220,512
(iv) Shared power to dispose
or to direct the
disposition of shares: 122,765
Item 5. Ownership of Five Percent or Less of a Class:
N/A
Item 6. Ownership of More than Five Percent on Behalf of Another Person:
Other persons have the right to receive or the power to direct the
receipt of dividends from or the proceeds from the sale of the
securities referred to in this schedule but no such interest related
to more than 5% of the class.
Item 7. Identification and Classification of the Subsidiary Which Acquired the
Security Being Reported by the Parent Holding Company:
N/A
Item 8. Identification and Classification of Members of the Group:
N/A
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CUSIP NO. 724508-106 SCHEDULE 13G PAGE 5 OF 5
Item 9. Notice of Dissolution of Group:
N/A
Item 10. Certification:
N/A
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I certify
that the information set forth in this statement is true, complete and correct.
Date: February 2, 1998
Signature: /s/ W. R. Jackson
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W. R. Jackson
Name/Title: W. R. Jackson
Chairman Emeritus
