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                                                                    Exhibit 10.1

                                ETHYL CORPORATION
                           INCENTIVE STOCK OPTION PLAN

                      As Amended Through February 25, 2002

                                    Article I

                                   DEFINITIONS

1.01  Affiliate means any Subsidiary or "parent corporation" (within the meaning
of Section 422A of the Code) of the Company.

1.02  Agreement means a written agreement (including any amendment or supplement
thereto) between the Company and a Participant specifying the terms and
conditions of an Option or SAR granted to such Participant.

1.03  Board means the Board of Directors of the Company.

1.04  Code means the Internal Revenue Code of 1986 as amended, and any successor
thereto.

1.05  Committee means a committee, consisting of not less than three members of
the Board, appointed by the Board to administer the Plan. No member of the
Committee shall be eligible to participate in the Plan.

1.06  Common Stock means the common stock of the Company.

1.07  Company means Ethyl Corporation.

1.08  Fair Market Value means, on any given date, the closing price of a share
of Common Stock as reported on the New York Stock Exchange composite tape on
such day or, if the Common Stock was not traded on the New York Stock Exchange
on such day, then on the next preceding day that the Common Stock was traded on
such exchange, all as reported by such source as the Committee may select. If
shares of Common Stock are not then traded on the New York Stock Exchange, the
Fair Market Value shall be determined by the Committee using any reasonable
method in good faith.

1.09  Option means a stock option that entitles the holder to purchase from the
Company a stated number of shares of Common Stock at the price set forth in an
Agreement.

1.10  Participant means an employee of the Company or of a Subsidiary, including
an employee who is a member of the Board, who satisfies the requirements of
Article IV and is selected by the Committee to receive an Option.

1.11  Plan means the Ethyl Corporation Incentive Stock Option Plan.

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1.12  SAR means a stock appreciation right (which may be granted only in
conjunction with an Option) that entitles the holder to receive, with respect to
each share of Common Stock encompassed by the exercise of such SAR, the lesser
of (a) the excess of the Fair Market Value at the time of exercise over the
option price of the related Option or (b) the Fair Market Value on the date of
grant. Such payment shall be made in Common Stock or in cash and Common Stock as
determined by the Committee in accordance with Section 8.03.

1.13  Subsidiary means any corporation (other than the Company) in an unbroken
chain of corporations beginning with the Company if each of the corporations in
the chain (other than the last corporation) owns stock possessing at least 50
percent of the total combined voting power of all classes of stock in one of the
other corporations in such chain.

                                   Article II

                                    PURPOSES

      This Plan is intended to assist the Company in recruiting and retaining
key employees with ability and initiative by enabling employees who contribute
significantly to the Company to participate in its future success and to
associate their interests with those of the Company. It is further intended that
Options granted under this Plan (unless otherwise designated by their terms)
shall constitute "incentive stock options" within the meaning of Section 422A of
the Code. No Option shall be invalid for failure to qualify as an incentive
stock option. The proceeds received by the Company from the sale of Common Stock
pursuant to this Plan shall be used for general corporate purposes.

                                  Article III

                                 ADMINISTRATION

      This Plan shall be administered by the Committee. The Committee shall have
authority to grant Options and SARs upon such terms (not inconsistent with the
provisions of this Plan) as the Committee may consider appropriate. Such terms
may include conditions (in addition to those contained in this Plan) on the
exercisability of all or any part of an Option or SAR. Notwithstanding any such
conditions, the Committee may, in its discretion, accelerate the time at which
any Option or SAR may be exercised; provided, however, that such acceleration
shall not affect the applicability of Section 7.04 (relating to the order in
which incentive stock options and related SARs may be exercised) or Section 4.02
(relating to the maximum number of shares for which an incentive Option or
related SAR may first become exercisable in any calendar year). In addition, the
Committee shall have complete authority to interpret all provisions of this
Plan; to prescribe the form of Agreements; to adopt, amend, and rescind rules
and regulations pertaining to the administration of this Plan; and to make all
other determinations necessary or advisable for the administration of this Plan.
The express grant in this Plan of any specific power to the Committee shall not
be construed as limiting any power or authority of the Committee. Any decision
made, or action taken,

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by the Committee in or in connection with the administration of this Plan shall
be final and conclusive. No member of the Committee shall be liable for any act
done in good faith with respect to this Plan or any Agreement, Option, or SAR.
All expenses of administering this Plan shall be borne by the Company.

                                   Article IV

                                   ELIGIBILITY

4.01  General. Any employee of the Company or of any Subsidiary (including any
corporation that becomes a Subsidiary after the adoption of this Plan) who, in
the judgment of the Committee, has contributed or can be expected to contribute
to the profits or growth of the Company or a Subsidiary may be granted one or
more Options and SARs. Directors of the Company who are employees and are not
members of the Committee are eligible to participate in this Plan.

4.02  Grants. The Committee will designate employees to whom Options and SARs
are to be granted and will specify the number of shares of Common Stock subject
to each grant. An Option may be granted with or without a related SAR. An SAR
may be granted only in conjunction with an Option and for a number of shares not
exceeding the number of shares subject to the related Option. All Options and
SARs granted under this Plan shall be evidenced by Agreements which shall be
subject to applicable provisions of this Plan and to such other provisions as
the Committee may adopt.

      With respect to Option grants prior to January 1, 1987, no Participant may
be granted incentive stock options (under all incentive stock option plans of
the Company and Affiliates) in any calendar year for stock having an aggregate
fair market value (determined as of the date an Option is granted) exceeding
$100,000 plus any unused limit carryover (as defined in Subsection 422A(c)(4) of
the Code) to such year. With respect to Options granted after December 31, 1986,
no Participant may be granted incentive stock options (under all incentive stock
option plans of the Company and Affiliates) which are first exercisable in any
calendar year for stock having an aggregate fair market value (determined as of
the date an Option is granted) exceeding $100,000. The preceding annual
limitations shall not apply with respect to Options that are not incentive stock
options.

      After April 28, 1994, no Participant may be granted Options and SARs in
any calendar year for more than 200,000 shares of Common Stock. For purposes of
this limitation, an Option and related SAR are treated as a single award.

                                   Article V

                        STOCK SUBJECT TO OPTIONS OR SARS

      Upon the exercise of any Option or SAR, the Company may deliver to the
Participant authorized but unissued stock, treasury stock, or any combination
thereof. The maximum aggregate number of shares of Common Stock that may be
issued

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pursuant to Options and SARs granted under this Plan is 11,900,000, subject to
adjustment as provided by Article IX. If an Option is terminated, in whole or in
part, for any reason other than its exercise or the exercise of a related SAR,
the number of shares of Common Stock allocated to the Option or portion thereof
may be reallocated to other Options to be granted under this Plan. If an SAR is
terminated, in whole or in part, for any reason other than its exercise or the
exercise of a related Option, the number of shares of Common Stock allocated to
the SAR or portion thereof may be reallocated to other SARs to be granted under
this Plan.

                                   Article VI

                                  OPTION PRICE

      The price per share for Common Stock purchased on the exercise of any
Option granted under this Plan shall be not less than the Fair Market Value on
the date the Option is granted.

                                  Article VII

                          EXERCISE OF OPTIONS AND SARS

7.01  Maximum Option or SAR Period. No Option or related SAR shall be
exercisable after the expiration of 10 years from the date the Option was
granted. The terms of any Option or SAR may provide that it is exercisable for a
period less than such maximum period.

7.02  Nontransferability. Any Option or SAR granted under this Plan shall be
nontransferable except by will or by the laws of descent and distribution. In
the event of any such transfer, the Option and related SAR must be transferred
to the same person(s). During the lifetime of the Participant to whom the Option
is granted, the Option or SAR may be exercised only by the Participant. No right
or interest of a Participant in any Option or SAR shall be liable for, or
subject to, any lien, obligation, or liability of such Participant.

7.03  Employee Status. For purposes of determining the applicability of Section
422A of the Code (relating to incentive stock options), or in the event that the
terms of any Option provide that it may be exercised only during employment or
within a specified period of time after termination of employment, the Committee
may decide in each case to what extent leaves of absence for governmental or
military service, illness, temporary disability, or other reasons shall not be
deemed interruptions of continuous employment.

7.04  Nonexercisability While Previously Granted Option Outstanding. No Option
which is an incentive stock option or related SAR and which was granted before
January 1, 1987, shall be exercisable by a Participant while that Participant
has outstanding (within the meaning of Subsection 422A(c)(7) of the Code) any
Option which was granted before the Option was granted and that is an incentive
stock option to

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purchase stock in the Company, in a corporation that (at the time the Option was
granted) is an Affiliate, or in a predecessor of any of such corporation.

                                  Article VIII

                               METHOD OF EXERCISE

8.01  Exercise. Subject to the provisions of Articles VII and X, an Option or
SAR may be exercised in whole at any time or in part from time to time at such
times and in compliance with such requirements as the Committee shall determine;
provided, however, that an SAR may be exercised only to the extent the related
Option is exercisable and when the Fair Market Value exceeds the option price of
the related Option. An Option or SAR granted under this Plan may be exercised
with respect to any number of whole shares less than the full number for which
the Option or SAR could be exercised. Such partial exercise of an Option or SAR
shall not affect the right to exercise the Option or SAR from time to time in
accordance with this Plan with respect to the remaining shares subject to the
Option or related to the SAR. The exercise of either an Option or SAR shall
result in the termination of the other to the extent of the number of shares
with respect to which the Option or SAR is exercised.

8.02  Payment. Unless otherwise provided by the Agreement or permitted by the
Committee, payment of the Option price shall be made in cash or such cash
equivalent as shall be acceptable to the Committee. If the Agreement provides or
the Committee permits, payment of all or a part of the Option price may be made
by surrendering shares of Common Stock to the Company. If Common Stock is used
to pay all or part of the Option price, the shares surrendered must have a fair
market value (determined by the Committee using any reasonable method in good
faith) that is not less than such price or part thereof.

8.03  Determination of Payment of Cash and/or Common Stock Upon Exercise of SAR.
If the Agreement provides or the Committee so determines, up to one-half of the
amount payable as a result of the exercise of an SAR may be settled by the
payment of cash and the remainder by the issuance of Common Stock having an
aggregate Fair Market Value equal thereto. In the absence of such provision or
determination, a Participant exercising an SAR shall be entitled to receive
Common Stock equal in aggregate Fair Market Value to the amount payable as a
result of the exercise of an SAR.

8.04  Shareholder Rights. No Participant shall, as a result of receiving any
Option or SAR, have any rights as a shareholder until the date he exercises such
Option or SAR.

                                   Article IX

                     ADJUSTMENT UPON CHANGE IN COMMON STOCK

      Should the Company affect one or more stock dividends, stock split-ups,
subdivisions or consolidations of shares or other similar changes in
capitalization, then the maximum number of shares as to which Options and SARs
may be granted under this

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Plan shall be proportionately adjusted and the terms of Options and SARs shall
be adjusted as the Committee shall determine to be equitably required. Any
determination made under this Article IX by the Committee shall be final and
conclusive.

       The issuance by the Company of shares of stock of any class, or
securities convertible into shares of stock of any class, for cash or property,
or for labor or services, either upon direct sale or upon the exercise of rights
or warrants to subscribe therefor, or upon conversion of shares or obligations
of the Company convertible into such shares or other securities, shall not
affect, and no adjustment by reason thereof shall be made with respect to,
Options or SARs.

                                   Article X

              COMPLIANCE WITH LAW AND APPROVAL OF REGULATORY BODIES

       No Option or SAR shall be exercisable, no Common Stock shall be issued,
no certificate for shares of Common Stock shall be delivered, and no payment be
made under this Plan except in compliance with all applicable federal and state
laws and regulations (including, without limitation, withholding tax
requirements) and the rules of all domestic stock exchanges on which the
Company's shares may be listed. The Company shall have the right to rely on an
opinion of its counsel as to such compliance. Any share certificate issued to
evidence Common Stock for which an Option or SAR is exercised may bear such
legends and statements as the Committee may deem advisable to assure compliance
with federal and state laws and regulations. No Option or SAR shall be
exercisable, no Common Stock shall be issued, no certificate for shares shall be
delivered, and no payment shall be made under this Plan until the Company has
obtained such consent or approval as the Committee may deem advisable from
regulatory bodies having jurisdiction over such matters.

                                   Article XI

                               GENERAL PROVISIONS

11.01  Effect on Employment. Neither the adoption of this Plan, its operation,
nor any documents describing or referring to this Plan (or any part thereof)
shall confer upon any employee any right to continue in the employ of the
Company or a Subsidiary or in any way affect any right and power of the Company
or a Subsidiary to terminate the employment of any employee at any time with or
without assigning a reason therefor.

11.02  Unfunded Plan. This Plan, insofar as it provides for grants, shall be
unfunded, and the Company shall not be required to segregate any assets that may
at any time be represented by grants under the Plan. Any liability of the
Company to any person with respect to any grant under this Plan shall be based
solely upon any contractual obligations which may be created pursuant to this
Plan. No such obligation of the Company shall be deemed to be secured by any
pledge of, or other encumbrance on, any property of the Company.

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11.03  Rules of Construction. Headings are given to the articles and sections of
this Plan solely as a convenience to facilitate reference. The reference to any
statute, regulation, or other provision of law shall be construed to refer to
any amendment to or successor of such provision of law.

                                   Article XII

                                    AMENDMENT

       The Board may amend or terminate this Plan from time to time; provided,
however, that no amendment may become effective until shareholder approval is
obtained if (i) the amendment increases the aggregate number of shares that may
be issued pursuant to Options and SARs, (ii) the amendment reduces the option
price, or (iii) the amendment changes the class of employees eligible to become
Participants. No amendment shall, without a Participant's consent, adversely
affect any rights of such Participant under any Option or SAR outstanding at the
time such amendment is made.

                                  Article XIII

                                DURATION OF PLAN

       No Option or SAR may be granted under this Plan after March 2, 2004.
Options and SARs granted before that date shall remain valid in accordance with
their terms.

                                  Article XIV

                             EFFECTIVE DATE OF PLAN

       Options and SARs may be granted under this Plan upon its adoption by the
Board, provided that no Option or SAR will be effective unless this Plan is
approved (at a duly held shareholders' meeting) by shareholders holding a
majority of the Company's outstanding voting stock within twelve months of such
adoption.

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