UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                 SCHEDULE 13G/A


                    Under the Securities Exchange Act of 1934
                                (Amendment No. 2)


                                TENNANT, COMPANY
                               -------------------
                                (Name of Issuer)


                                  COMMON STOCK
                         ------------------------------
                         (Title of Class of Securities)


                                    880345103
                                 --------------
                                 (CUSIP Number)


                                DECEMBER 31, 2004
             -------------------------------------------------------
             (Date of Event which Requires Filing of this Statement)


Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

[X]  Rule 13d-1(b)
|_|  Rule 13d-1(c)
|_|  Rule 13d-1(d)

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).


                                Page 1 of 8 Pages


CUSIP NO. 880345103                                            PAGE 2 OF 8 PAGES


                                  SCHEDULE 13G

     1     NAME OF REPORTING PERSON
           SS. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

           Fenimore Asset Management, Inc.
           14-1564237

     2     CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP    (A)  |_|
                                                               (B)  [X]

     3     SEC USE ONLY

     4     CITIZENSHIP OR PLACE OF ORGANIZATION
           New York State

                                5      SOLE VOTING POWER
     NUMBER OF SHARES                  610,205
  BENEFICIALLY OWNED BY
EACH REPORTING PERSON WITH
                                6      SHARED VOTING POWER
                                       0

                                7      SOLE DISPOSITIVE POWER
                                       610,205

                                8      SHARED DISPOSITIVE POWER
                                       0

     9     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
           610,205

     10    CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
                                                                    |_|

     11    PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
           6.78%

     12    TYPE OF REPORTING PERSON
           IA


CUSIP NO. 880345103                                            PAGE 3 OF 8 PAGES


                                  SCHEDULE 13G

     1     NAME OF REPORTING PERSON
           SS. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

           Thomas O. Putnam
           N/A

     2     CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP    (A)  |_|
                                                               (B)  [X]

     3     SEC USE ONLY

     4     CITIZENSHIP OR PLACE OF ORGANIZATION
           United States

                                5      SOLE VOTING POWER
     NUMBER OF SHARES                  610,205
  BENEFICIALLY OWNED BY
EACH REPORTING PERSON WITH
                                6      SHARED VOTING POWER
                                       0

                                7      SOLE DISPOSITIVE POWER
                                       610,205

                                8      SHARED DISPOSITIVE POWER
                                       0

     9     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
           610,205

     10    CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
                                                                    |_|

     11    PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
           6.78%

     12    TYPE OF REPORTING PERSON
           IN


CUSIP NO. 880345103                                            PAGE 4 OF 8 PAGES


                                  SCHEDULE 13G

Item 1.    (a).    Name of Issuer:  Tennant Company

           (b).    Address of Issuer's Principal Executive Offices:

                     701 North Lilac Drive
                     Minneapolis, MN 55440

Item 2.    (a).    Name of Persons Filing:

                     (i)  Fenimore Asset Management, Inc. ("Fenimore")
                     (ii) Thomas O. Putman ("Putnam")

           (b).    Address of Principal Business Office for Each of the Above:

                     384 N. Grand Street, Box 310
                     Cobleskill, NY 12043

           (c).    Citizenship or Place of Organization:

                     (i)  Fenimore:  New York State
                     (ii) Putnam:     United States

           (d).    Title of Class of Securities:  Common Stock

           (e).    CUSIP Number:  880345103

Item 3.    If this Statement is Filed Pursuant to Rules 13d-1(b) or 13d-2(b)
           or (c), Check Whether the Person Filing is a:

                   (a) [ ] Broker or dealer registered under Section 15 of the
                           Exchange Act;
                   (b) [ ] Bank as defined in Section 3(a)(6) of the Exchange
                           Act;
                   (c) [ ] Insurance company as defined in Section 3(a)(19) of
                           the Exchange Act;
                   (d) [ ] Investment company registered under Section 8 of the
                           Investment Company Act;
                   (e) [x] An investment adviser in accordance with Rule
                           13d-1(b)(1)(ii)(E);
                   (f) [ ] An employee benefit plan or endowment fund in
                           accordance with Rule 13d-1(b)(1)(ii)(F);
                   (g) [ ] A parent holding company or control person in
                           accordance with Rule 13d-1(b)(1)(ii)(G);


CUSIP NO. 880345103                                            PAGE 5 OF 8 PAGES


                                  SCHEDULE 13G

                   (h) [ ] A savings associations as defined in Section 3(b) of
                           the Federal Deposit Insurance Act;
                   (i) [ ] A church plan that is excluded from the definition of
                           an investment company under Section 3(c)(14) of the
                           Investment Company Act of 1940;
                   (j) [ ] Group, in accordance with Rule 13d-1(b)(1) (ii)(J).

Item 4.      Ownership.

           (a).    Amount beneficially owned:
                   (i)  Fenimore:       610,205
                   (ii) Putnam:         610,205

           (b).    Percent of class:
                   (i)  Fenimore:       6.78%
                   (ii) Putnam:         6.78%

           (c).    Number of shares as to which such person has:

                   (1) Sole power to vote or to direct the vote:

                       (i)  Fenimore:       610,205
                       (ii) Putnam:               0

                   (2) Shared power to vote or to direct the vote:

                       (i)  Fenimore:             0
                       (ii) Putnam:         610,205

                   (3) Sole power to dispose or to direct the disposition of:

                       (i)  Fenimore:       610,205
                       (ii) Putnam:               0

                   (4) Shared power to dispose or to direct the disposition of:

                       (i)  Fenimore:             0
                       (ii) Putnam:         610,205


CUSIP NO. 880345103                                            PAGE 6 OF 8 PAGES


                                  SCHEDULE 13G

Item 5.    Ownership of Five Percent or Less of a Class:

           Not Applicable

Item 6.    Ownership of More Than Five Percent on Behalf of Another Person:

           Not Applicable.

Item 7.    Identification and Classification of Subsidiaries which Acquired the
           Security Being Reported on by the Parent Holding Company:

           Not Applicable

Item 8.    Identification and Classification of Members of the Group:

           Not Applicable

Item 9.    Notice of Dissolution of Group:

           Not Applicable

Item 10.   Certification:

           By signing below, I certify that, to the best of my knowledge and
           belief, the securities referred to above were acquired and are held
           in the ordinary course of business and were not acquired and are not
           held for the purpose of or with the effect of changing or influencing
           the control of the issuer of the securities and were not acquired and
           are not held in connection with or as a participant in any
           transaction having that purpose or effect.

           In accordance with Rule 13d-4 of the Securities Exchange Act of 1934,
           each of the persons filing this statement expressly disclaim the
           beneficial ownership of the securities covered by this statement and
           the filing of this report shall not be construed as an admission by
           such persons that they are the beneficial owners of such securities.



CUSIP NO. 880345103                                            PAGE 7 OF 8 PAGES


                                  SCHEDULE 13G

                                   SIGNATURES

     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.

                                       FENIMORE ASSET MANAGEMENT, INC.


Date:  February 4, 2005                By: /S/ JOSEPH A. BUCCI
                                           ----------------------------
                                           Joseph A. Bucci
                                           Secretary and Compliance Officer


                                       THOMAS O. PUTNAM


Date:  February 4, 2005                By: /S/ THOMAS O. PUTNAM
                                           -----------------------------
                                           Thomas O. Putman


CUSIP NO. 880345103                                            PAGE 8 OF 8 PAGES


                                  SCHEDULE 13G

                                    EXHIBIT 1

JOINT FILING AGREEMENT AMONG FENIMORE ASSET MANAGEMENT, INC.
AND THOMAS O. PUTNAM

WHEREAS, in accordance with Rule 13d-1(k) under the Securities and Exchange Act
of 1934 (the "Act"), only one joint statement and any amendments thereto need to
be filed whenever one or more persons are required to file such a statement or
any amendments thereto pursuant to Section 13(d) of the Act with respect to the
same securities, provided that said persons agree in writing that such statement
or amendments thereto is filed on behalf of each of them;

NOW, THEREFORE, the parties hereto agree as follows:

FENIMORE ASSET MANAGEMENT, INC. AND THOMAS O. PUTNAM hereby agree, in accordance
with Rule 13d-1(k) under the Act, to file a statement on Schedule 13G relating
to their ownership of Common Stock of the Issuer and do hereby further agree
that said statement shall be filed on behalf of each of them.

                                       FENIMORE ASSET MANAGEMENT, INC.


Date:  February 4, 2005                By: /S/ JOSEPH A. BUCCI
                                           ----------------------------
                                           Joseph A. Bucci
                                           Secretary and Compliance Officer


                                       THOMAS O. PUTNAM


Date:  February 4, 2005                By: /S/ THOMAS O. PUTNAM
                                           -----------------------------
                                           Thomas O. Putnam