SECURITIES AND EXCHANGE COMMISSION
                             Washington, D. C. 20549
                                  SCHEDULE l3D
                                (Amendment No. 3)
                    Under the Securities Exchange Act of 1934


                                   OCTEL CORP.
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                                (Name of Issuer)

                     Common Stock, par value $0.01 per share
- --------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                    67572710
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                                 (CUSIP Number)

                                                 with a copy to:
Jeffrey S. Halis                                 Robert G. Minion, Esq.
500 Park Avenue                                  Lowenstein Sandler PC
Fifth Floor                                      65 Livingston Avenue
New York, New York  10022                        Roseland, New Jersey  07068
(212) 378-0879                                   (973) 597-2424

- --------------------------------------------------------------------------------
                  (Name, Address and Telephone Number of Person
                Authorized to Receive Notices and Communications)

                                November 19, 1998
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             (Date of Event which Requires Filing of this Statement)

If the filing person has previously  filed a statement on Schedule l3G to report
the  acquisition  which is the subject of this  Schedule 13D, and is filing this
schedule  because  of  Section  240.13d-1(e),  Section  240.13d-1(f)  or Section
240.13d-1(g), check the following box. [ ]

Note:  Schedules filed in proper format shall include a signed original and five
copies of the schedule, including all exhibits. See Rule l3d-7 for other parties
to whom copies are to be sent.

*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
disclosures provided in a prior cover page.

The information required on 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).


- -------------------------------------------------------------------------------- 1) Names of Reporting Persons. I.R.S. Identification Nos. of Above Persons (Entities Only): Jeffrey S. Halis - -------------------------------------------------------------------------------- 2) Check the Appropriate Box if a Member of a Group (See Instructions): (a) Not (b) Applicable - -------------------------------------------------------------------------------- 3) SEC Use Only - -------------------------------------------------------------------------------- 4) Source of Funds (See Instructions): WC - -------------------------------------------------------------------------------- 5) Check if Disclosure of Legal Proceedings is Required Pursuant to Items 2(d) or 2(e): Not Applicable - -------------------------------------------------------------------------------- 6) Citizenship or Place of Organization: United States - -------------------------------------------------------------------------------- Number of 7) Sole Voting Power: 1,754,600* Shares Beneficially -------------------------------------- Owned by 8) Shared Voting Power: 0 Each Reporting -------------------------------------- Person With: 9) Sole Dispositive Power: 1,754,600* -------------------------------------- 10) Shared Dispositive Power: 0 -------------------------------------- - -------------------------------------------------------------------------------- 11) Aggregate Amount Beneficially Owned by Each Reporting Person: 1,754,600* - -------------------------------------------------------------------------------- 12) Check if the Aggregate Amount in Row (11) Excludes Certain Shares (See Instructions): Not Applicable - -------------------------------------------------------------------------------- 13) Percent of Class Represented by Amount in Row (11): 12.5%* - -------------------------------------------------------------------------------- 14) Type of Reporting Person (See Instructions): IA - -------------------------------------------------------------------------------- * 860,500 shares (6.1%) of Octel Corp. common stock are owned by Tyndall Partners, L.P., a Delaware limited partnership. 437,700 shares (3.1%) of Octel Corp. common stock are owned by Tyndall Institutional Partners, L.P., a Delaware limited partnership. 117,500 shares (0.8%) of Octel Corp. common stock are owned by Madison Avenue Partners, L.P., a Delaware limited partnership. 338,900 shares (2.4%) of Octel Corp. common stock are owned by Halo International, Ltd., a company organized under the laws of the Cayman Islands. Pursuant to the Agreement of Limited Partnership of each of Tyndall Partners, L.P., Tyndall Institutional Partners, L.P., and Madison Avenue Partners, L.P. and the Investment Management Agreement of Halo International, Ltd., Jeffrey S. Halis possesses sole voting and investment control over all securities owned by each of Tyndall Partners, L.P., Tyndall Institutional Partners, L.P., Madison Avenue Partners, L.P., and Halo International, Ltd., respectively. See Item 5 for further information on the computation of percentages set forth herein.

Item 5. Interest in Securities of the Issuer. Based upon information set forth in Octel Corp.'s Form 10-Q for the fiscal quarter ended September 30, 1998, as of October 31, 1998, there were 14,027,325 shares of Octel Corp. common stock issued and outstanding. As of November 19, 1998, Tyndall Partners, L.P. owned 860,500 of such shares, or 6.1% of those outstanding, Tyndall Institutional Partners, L.P. owned 437,700 of such shares, or 3.1% of those outstanding, Madison Avenue Partners, L.P. owned 117,500 of such shares, or 0.8% of those outstanding, and Halo International, Ltd. owned 338,900 of such shares, or 2.4% of those outstanding. Jeffrey Halis possesses sole power to vote and direct the disposition of all shares of common stock of Octel Corp. owned by each of Tyndall Partners, L.P., Tyndall Institutional Partners, L.P., Madison Avenue Partners, L.P. and Halo International, Ltd. The following table details the transactions by each of Tyndall Partners, L.P., Tyndall Institutional Partners, L.P., Madison Avenue Partners, L.P. and Halo International, Ltd. in shares of common stock of Octel Corp. during the past sixty days (each of which were effected in an ordinary brokers transaction): A. Tyndall Partners, L.P. Date Quantity Price (Purchases) November 19, 1998 9,400 $13.25 (Sales) NONE B. Tyndall Institutional Partners, L.P. Date Quantity Price November 17, 1998 5,500 $13.36 November 18, 1998 28,500 13.19 November 19, 1998 75,600 13.25 (Sales) NONE C. Madison Avenue Partners, L.P. Date Quantity Price (Purchases) NONE (Sales) NONE D. Halo International, Ltd. Date Quantity Price (Purchases) NONE (Sales) NONE 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. November 25, 1998 /s/Jeffrey S. Halis -------------------------------------- Jeffrey S. Halis, as a general partner of Halo Capital Partners, L.P., the general partner of each of Tyndall Partners, L.P., Tyndall Institutional Partners, L.P. and Madison Avenue Partners, L.P. and as a member of Jemi Management, L.L.C., the Investment Manager for Halo International, Ltd. ATTENTION: INTENTIONAL MISSTATEMENTS OR OMISSIONS OF FACT CONSTITUTE FEDERAL CRIMINAL VIOLATIONS (SEE 18 U.S.C. 1001).