EXHIBIT (A)(4)

                          OFFER TO PURCHASE FOR CASH
                Any and All Outstanding Shares of Common Stock

                                      of

                          Johns Manville Corporation

                                      at

                             $13.00 Net per Share

                                      by

                           J Acquisition Corporation
                         a wholly owned subsidiary of

                            Berkshire Hathaway Inc.

 THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY
       TIME, ON MONDAY, JANUARY 29, 2001, UNLESS THE OFFER IS EXTENDED.


                                                              December 29, 2000

To Brokers, Dealers, Commercial Banks,
Trust Companies, and Other Nominees:

  We have been appointed by J Acquisition Corporation, a Delaware corporation
("Purchaser") and wholly owned subsidiary of Berkshire Hathaway Inc., a
Delaware corporation ("Parent"), to act as Information Agent in connection
with Purchaser's offer to purchase any and all outstanding shares of Common
Stock, par value $0.01 per share ("Shares"), of Johns Manville Corporation, a
Delaware corporation (the "Company"), at $13.00 per Share, net to the seller
in cash, upon the terms and subject to the conditions set forth in the Offer
to Purchase dated December 29, 2000, and in the related Letter of Transmittal
(which together with the Offer to Purchase and any amendments and supplements
thereto collectively constitute the "Offer") enclosed herewith. Please furnish
copies of the enclosed materials to those of your clients for whose accounts
you hold Shares registered in your name or in the name of your nominee.

  The Offer is conditioned upon, among other things, the receipt of an order
of the United States Bankruptcy Court for the Southern District of New York
approving, among other things, the tender by the Manville Personal Injury
Settlement Trust (the "Manville Trust") of Shares held by it, and upon the
Amended and Restated Tax Matters and Amended Trust Relationship Agreement
between the Company and the Manville Trust being in full force and effect (and
all relevant conditions to the transactions described therein--other than the
consummation of the Offer--being satisfied or waived), both of which are
discussed in the Offer to Purchase. The Offer is also subject to other
conditions set forth in the Offer to Purchase.

  For your information and for forwarding to your clients for whom you hold
Shares registered in your name or in the name of your nominee, we are
enclosing the following documents:

  1. Offer to Purchase dated December 29, 2000;

  2. Letter of Transmittal for your use in accepting the Offer and tendering
Shares and for the information of your clients;

  3. Notice of Guaranteed Delivery to be used to accept the Offer if
certificates for Shares and all other required documents cannot be delivered
to the Depositary, or if the procedures for book-entry transfer cannot be
completed, by the Expiration Date (as defined in the Offer to Purchase);


  4. A letter which may be sent to your clients for whose accounts you hold
Shares registered in your name or in the name of your nominee, with space
provided for obtaining such clients' instructions with regard to the Offer;

  5. Guidelines for Certification of Taxpayer Identification Number on
Substitute Form W-9;

  6. A return envelope addressed to EquiServe Trust Company, N.A. (the
"Depositary"); and

  7. A letter from Charles L. Henry, Chairman, President and Chief Executive
Officer of the Company, accompanied by the Company's
Solicitation/Recommendation Statement on Schedule 14D-9.

  Upon the terms and subject to the conditions of the Offer (including, if the
Offer is extended or amended, the terms and conditions of any such extension
or amendment), Purchaser will accept for payment and pay for Shares which are
validly tendered prior to the Expiration Date and not theretofore properly
withdrawn when, as and if Purchaser gives oral or written notice to the
Depositary of Purchaser's acceptance of such Shares for payment pursuant to
the Offer. Payment for Shares purchased pursuant to the Offer will in all
cases be made only after timely receipt by the Depositary of (i) certificates
for such Shares, or timely confirmation of a book-entry transfer of such
Shares into the Depositary's account at The Depositary Trust Company, pursuant
to the procedures described in Section 3 of the Offer to Purchase, (ii) a
properly completed and duly executed Letter of Transmittal (or a properly
completed and manually signed facsimile thereof) or an Agent's Message (as
defined in the Offer to Purchase) in connection with a book-entry transfer,
and (iii) all other documents required by the Letter of Transmittal.

  Purchaser will not pay any fees or commissions to any broker or dealer or
other person (other than the Information Agent and the Depositary as described
in the Offer to Purchase) for soliciting tenders of Shares pursuant to the
Offer. Purchaser will, however, upon request, reimburse brokers, dealers,
commercial banks, and trust companies for customary mailing and handling costs
incurred by them in forwarding the enclosed materials to their customers.

  Purchaser will pay or cause to be paid all stock transfer taxes applicable
to its purchase of Shares pursuant to the Offer, subject to Instruction 6 of
the Letter of Transmittal.

  WE URGE YOU TO CONTACT YOUR CLIENTS AS PROMPTLY AS POSSIBLE. PLEASE NOTE
THAT THE OFFER AND WITHDRAWAL RIGHTS EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY
TIME, ON MONDAY, JANUARY 29, 2001, UNLESS THE OFFER IS EXTENDED.

  In order to take advantage of the Offer, a duly executed and properly
completed Letter of Transmittal (or facsimile thereof), with any required
signature guarantees, or an Agent's Message in connection with a book-entry
transfer of Shares, and any other required documents, should be sent to the
Depositary, and certificates representing the tendered Shares should be
delivered or such Shares should be tendered by book-entry transfer, all in
accordance with the Instructions set forth in the Letter of Transmittal and in
the Offer to Purchase.

  If holders of Shares wish to tender, but it is impracticable for them to
forward their certificates or other required documents or to complete the
procedures for delivery by book-entry transfer prior to the expiration of the
Offer, a tender may be effected by following the guaranteed delivery
procedures specified in Section 3 of the Offer to Purchase.


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  Any inquiries you may have with respect to the Offer should be addressed to,
and additional copies of the enclosed materials may be obtained from,
Georgeson Shareholder Communications Inc., the Information Agent, at the
address and telephone number set forth on the back cover of the Offer to
Purchase.

                                          Very truly yours,

                                          Georgeson Shareholder
                                          Communications Inc.

  NOTHING CONTAINED HEREIN OR IN THE ENCLOSED DOCUMENTS SHALL CONSTITUTE YOU
THE AGENT OF PARENT, PURCHASER, THE COMPANY, THE INFORMATION AGENT, THE
DEPOSITARY OR ANY AFFILIATE OF ANY OF THE FOREGOING, OR AUTHORIZE YOU OR ANY
OTHER PERSON TO USE ANY DOCUMENT OR MAKE ANY STATEMENT ON BEHALF OF ANY OF
THEM IN CONNECTION WITH THE OFFER OTHER THAN THE DOCUMENTS ENCLOSED HEREWITH
AND THE STATEMENTS CONTAINED THEREIN.

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