SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549
                            -------------------------

                                   FORM 8-A/A
                                 Amendment No. 1

                FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
                     PURSUANT TO SECTION 12(b) OR (g) OF THE
                         SECURITIES EXCHANGE ACT OF 1934


                                   WICOR, Inc.
             (Exact name of registrant as specified in its charter)


            Wisconsin                                       39-1346701
     -----------------------                            ------------------
     (State of incorporation                               (IRS Employer
        or organization)                                Identification No.)


    626 East Wisconsin Avenue, Milwaukee, Wisconsin            53202
    -----------------------------------------------          ---------
      (Address of principal executive offices)               (Zip Code)


Securities to be registered pursuant to Section 12(b) of the Act:

Title of each class to be so            Name of each exchange on which each
registered                              class is to be registered
- ----------------------------            -----------------------------------
Common Share Purchase Rights            New York Stock Exchange

If this Form relates to the  registration  of a class of securities  pursuant to
Section  12(b)  of  the  Exchange  Act  and is  effective  pursuant  to  General
Instruction A.(c), please check the following box. [X]

If this Form relates to the  registration  of a class of securities  pursuant to
Section  12(g)  of  the  Exchange  Act  and is  effective  pursuant  to  General
Instruction A.(d), please check the following box. [ ]

Securities  Act  registration  statement file number to which this form relates:
Not applicable

Securities to be registered pursuant to Section 12(g) of the Act:

                                      None




Item 1.   Description of Registrant's Securities to be Registered.

          Reference  is hereby made to the  Registration  Statement  on Form 8-A
filed with the Securities and Exchange Commission by WICOR, Inc. (the "Company")
on July 29, 1999 (the "Form  8-A").  The Form 8-A relates to the share  purchase
rights (the "Rights") of the Company and the Rights  Agreement  dated as of July
27, 1999 (the "Rights  Agreement"),  by and between the Company and  ChaseMellon
Shareholder Services, L.L.C., as Rights Agent.

          The Company  has entered  into an  amendment  to the Rights  Agreement
dated as of September 9, 1999  ("Amendment  No. 1"), a copy of which is attached
hereto as Exhibit 4.2 and is incorporated  herein by reference.  Amendment No. 1
amends the definition of "Acquiring  Person" in the Rights  Agreement by raising
the beneficial ownership percentage threshold to become an Acquiring Person, and
at which the Rights become exercisable,  from 15% to 20% of the common shares of
the Company then outstanding.  Except as otherwise  provided in Amendment No. 1,
the other  provisions  of the Rights  Agreement  are not  otherwise  amended and
continue in full force and effect.

          Pursuant to the terms of the Rights  Agreement as originally  adopted,
the Board of Directors of the Company,  on July 27, 1999, declared a dividend of
one common share  purchase  Right for each  outstanding  share of common  stock,
$1.00 par value, of the Company (the "Common Shares").  The dividend was paid on
August 29, 1999 to the  shareholders of record on that date (the "Record Date").
Each Right entitles the registered  holder to purchase from the Company one-half
of one Common Share, at a price of $75.00 per Common Share (equivalent to $37.50
for each  one-half of a Common  Share),  subject to  adjustment  (the  "Purchase
Price").  The  description  and terms of the  Rights are set forth in the Rights
Agreement, as amended by Amendment No. 1 (the "Amended Rights Agreement").

          The Amended Rights Agreement provides that, until the earlier to occur
of (i) 10 days  following  a  public  announcement  that a  person  or  group of
affiliated or associated  persons  (other than the Company,  a subsidiary of the
Company, an employee benefit plan of the Company or a subsidiary) (an "Acquiring
Person") has  acquired  beneficial  ownership of 20% or more of the  outstanding
Common Shares (the "Shares  Acquisition Date") or (ii) 10 business days (or such
later date as may be determined  by action of the  Company's  Board of Directors
prior to such time as any person  becomes an  Acquiring  Person)  following  the
commencement  of, or  announcement  of an  intention  to make, a tender offer or
exchange  offer  the  consummation  of  which  would  result  in the  beneficial
ownership  by a person or group (other than the  Company,  a  subsidiary  of the
Company or an employee  benefit plan of the Company or a  subsidiary)  of 20% or
more of such  outstanding  Common Shares (the earlier of such dates being called
the "Distribution  Date"), the Rights will be evidenced,  with respect to any of
the Common Share certificates  outstanding as of the Record Date, by such Common
Share certificate.

          Until the  Distribution  Date, the Rights will be transferred with and
only with the Common Shares.  Until the Distribution Date (or earlier redemption
or expiration  of the Rights),  new Common Share  certificates  issued after the
Record  Date,  upon  transfer or new issuance of Common  Shares,  will contain a
notation  incorporating  the Amended  Rights  Agreement by reference.  Until the
Distribution  Date (or earlier  redemption  or  expiration  of the Rights),  the
surrender for transfer of any certificates for Common Shares,  outstanding as of
the Record Date,  even without such notation,  will also constitute the transfer
of the Rights associated with the Common Shares represented by such certificate.
As soon as practicable  following the Distribution Date,  separate  certificates
evidencing the Rights ("Right Certificates") will be mailed to holders of record
of the Common  Shares as of the close of business on the  Distribution  Date and
such separate Right Certificates alone will evidence the Rights.


                                      -2-


          The Rights are not exercisable until the Distribution Date. The Rights
will expire on August 29, 2009 (the "Final Expiration Date"),  unless the Rights
are  earlier  redeemed  or  exchanged  by the  Company,  or the  Amended  Rights
Agreement is amended, in each case as described below.

          The Purchase Price  payable,  and the number of Common Shares or other
securities  or  property  issuable,  upon  exercise of the Rights are subject to
adjustment  from time to time to  prevent  dilution  (i) in the event of a stock
dividend on, or a subdivision,  combination or  reclassification  of, the Common
Shares; (ii) upon the grant to holders of the Common Shares of certain rights or
warrants to subscribe for or purchase  Common  Shares at a price,  or securities
convertible  into  Common  Shares  with a  conversion  price  less than the then
current market price of the Common  Shares;  or (iii) upon the  distribution  to
holders of the Common Shares of evidences of indebtedness  or assets  (excluding
regular  quarterly cash  dividends or dividends  payable in Common Shares) or of
subscription rights or warrants (other than those referred to above).

          The  number of  outstanding  Rights  and the  number of Common  Shares
issuable upon exercise of each Right are also subject to adjustment in the event
of a stock split of the Common  Shares or a stock  dividend on the Common Shares
payable in Common Shares or subdivisions,  consolidations or combinations of the
Common Shares occurring, in any such case, prior to the Distribution Date.

          In the event that any person  becomes an Acquiring  Person (a "Flip-In
Event"),  holders of Rights will thereafter  generally have the right to receive
upon exercise that number of Common Shares (or, in certain  circumstances  cash,
property  or other  securities  of the Company or a  reduction  in the  Purchase
Price)  having a market  value of two times  the then  current  Purchase  Price.
Notwithstanding  any of the  foregoing,  following  the  occurrence of a Flip-In
Event all Rights  that are, or (under  certain  circumstances  specified  in the
Amended Rights Agreement) were, or subsequently  become beneficially owned by an
Acquiring Person, related persons and transferees will be null and void.

          In the event that, at any time following the Shares  Acquisition Date,
(i)  the  Company  is  acquired  in  a  merger  or  other  business  combination
transaction or (ii) 50% or more of its consolidated  assets or earning power are
sold (the events  described  in clauses  (i) and (ii) are herein  referred to as
"Flip-Over  Events"),  proper  provision  will be made so that holders of Rights
will  (subject to the  limitations  set forth in the Amended  Rights  Agreement)
thereafter  have the right to  receive,  upon the  exercise  thereof at the then
current  Purchase Price,  that number of shares of common stock of the acquiring
company  which at the time of such  transaction  will have a market value of two
times the then current Purchase Price.

          With certain  exceptions,  no adjustment in the Purchase Price will be
required until  cumulative  adjustments  require an adjustment of at least 1% in
such  Purchase  Price.  No fractional  Common Shares will be issued.  In lieu of
fractional  Common  Shares  equal  to  one-half  of a Common  Share or less,  an
adjustment  in cash will be made based on the market price of the Common  Shares
on the last  trading  day  prior  to the  date of  exercise.  No  Rights  may be
exercised that would entitle the holder  thereof to any fractional  Common Share
greater  than  one-half of a Common  Share unless  concurrently  therewith  such
holder purchases an additional  fraction of a Common Share,  which when added to
the  number  of Common  Shares to be  received  upon  such  exercise,  equals an
integral number of Common Shares.


                                      -3-


          The Purchase  Price is payable by certified  check,  cashier's  check,
bank draft or money order or, if so provided by the Company,  the Purchase Price
following the occurrence of a Flip-In Event and until the first  occurrence of a
Flip-Over Event may be paid in Common Shares having an equivalent value.

          At any time after a person  becomes an  Acquiring  Person and prior to
the acquisition by any Acquiring Person of 50% or more of the outstanding Common
Shares,  the Board of Directors  of the Company may  exchange the Rights  (other
than Rights owned by any Acquiring  Person which have become void),  in whole or
in part,  at an  exchange  ratio of one  Common  Share  per  Right  (subject  to
adjustment).

          At any time prior to a person becoming an Acquiring Person,  the Board
of Directors of the Company may redeem the Rights in whole,  but not in part, at
a price of $.001 per Right  (the  "Redemption  Price").  The  redemption  of the
Rights  may be made  effective  at  such  time,  on such  basis  and  with  such
conditions  as the Board of  Directors  in its sole  discretion  may  establish.
Immediately upon any redemption of the Rights,  the right to exercise the Rights
will  terminate  and the only right of the  holders of Rights will be to receive
the Redemption Price.

          Other than amendments  that would change the Redemption  Price or move
to an earlier date the expiration of the Rights,  the terms of the Rights may be
amended by the Board of  Directors  of the  Company  without  the consent of the
holders  of the  Rights,  including  an  amendment  to lower the  threshold  for
exercisability  of the Rights  from 20% to not less than 10%,  with  appropriate
exceptions for any person then beneficially owning a percentage of the number of
Common  Shares  then  outstanding  equal to or in excess  of the new  threshold,
except that from and after the Distribution Date no such amendment may adversely
affect the interests of the holders of the Rights.

          Until a Right is exercised,  the holder thereof, as such, will have no
rights as a shareholder of the Company, including, without limitation, the right
to vote or to receive dividends.

          As of July 26, 1999,  there were  37,503,735  Common Shares issued and
outstanding.  Each  outstanding  Common  Share on the Record Date  received  one
Right. As long as the Rights are attached to the Common Shares, the Company will
issue one Right for each Common  Share  which  becomes  outstanding  between the
Record Date and the Distribution Date so that all such shares will have attached
Rights.

          The Rights have certain  anti-takeover  effects. The Rights will cause
substantial  dilution to a person or group that  attempts to acquire the Company
without  conditioning  the offer on redemption of the Rights or on a substantial
number of Rights being acquired. The Rights should not interfere with any merger
or other business  combination approved by the Board of Directors of the Company
prior to the time that the Rights may not be redeemed (as described above) since
the  Board of  Directors  may,  at its  option,  at any time  until  the  Shares
Acquisition Date redeem all but not less than all the then outstanding Rights at
$.001 per Right.  The  Rights are  designed  to  provide  additional  protection
against abusive takeover tactics such as offers for all shares at less than full
value or at an inappropriate time (in terms of maximizing long-term  shareholder
value),  partial tender offers and selective open-market  purchases.  The Rights
are intended to assure that the Company's  Board of Directors has the ability to
protect  shareholders and the Company if efforts are made to gain control of the
Company in a manner  that is not in the best  interests  of the  Company and its
shareholders.


                                      -4-


          The Rights  Agreement and Amendment No. 1 thereto  between the Company
and the Rights  Agent  specifying  the terms of the  Rights,  which  includes as
Exhibit A the Form of Right Certificate, are incorporated herein by reference to
Exhibits 4.1 and 4.2 hereto.  The foregoing  description  of the Rights does not
purport to be complete  and is  qualified  in its  entirety by reference to such
exhibits.


                                      -5-


Item 2.   Exhibits.

          (4.1)     Rights Agreement,  dated as of July 27, 1999, by and between
                    WICOR, Inc. and ChaseMellon Shareholder Services, L.L.C., as
                    Rights Agent  [incorporated by reference to Exhibit (4.1) to
                    the Registration  Statement on Form 8-A of WICOR, Inc. dated
                    as of July 27, 1999 (Commission File No. 1-7951)]

          (4.2)     Amendment  No. 1, dated as of September  9, 1999,  to Rights
                    Agreement,  dated as of July 27, 1999, by and between WICOR,
                    Inc. and ChaseMellon Shareholder Services, L.L.C., as Rights
                    Agent.


          All exhibits  required by the  instructions to Item 2 will be supplied
          to the New York Stock Exchange.


                                      -6-



                                    SIGNATURE

          Pursuant to the requirements of Section 12 of the Securities  Exchange
Act of 1934, the registrant has duly caused this Amendment No. 1 to Registration
Statement  on Form 8-A to be signed on its  behalf by the  undersigned,  thereto
duly authorized.

                                   WICOR, INC.


Date:  September 9, 1999           By: /s/ Joseph P. Wenzler
                                      --------------------------------
                                      Joseph P. Wenzler
                                      Senior Vice President and Chief
                                      Financial Officer


                                      -7-



                                   WICOR, Inc.
                                    FORM 8-A
                                  EXHIBIT INDEX


Exhibit
Number                   Description
- -------                  -----------

(4.1)     Rights  Agreement,  dated as of July 27, 1999,  by and between  WICOR,
          Inc. and ChaseMellon  Shareholder  Services,  L.L.C.,  as Rights Agent
          [incorporated  by  reference  to  Exhibit  (4.1)  to the  Registration
          Statement  on Form  8-A of  WICOR,  Inc.  dated  as of July  27,  1999
          (Commission File No. 1-7951)]

(4.2)     Amendment No. 1, dated as of September 9, 1999,  to Rights  Agreement,
          dated as of July 27, 1999, by and between WICOR,  Inc. and ChaseMellon
          Shareholder Services, L.L.C., as Rights Agent.