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                                                                   EXHIBIT 10.42


                       SECOND AMENDMENT TO LEASE AGREEMENT

         THIS SECOND AMENDMENT TO LEASE AGREEMENT (hereinafter referred to as
the "Second Amendment") is made as of the _______ day of __________ 1997, by and
between WEEKS REALTY, L.P. (hereinafter referred to as "Landlord") and BIOFIELD
CORP. (hereinafter referred to as "Tenant").

                                   WITNESSETH:

         WHEREAS, North Meadow Associates Joint Venture and Tenant entered into
that certain Lease Agreement dated January 28, 1994, as amended by that certain
First Amendment to Lease dated July 26, 1994 (hereinafter collectively referred
to as the "Agreement") for the lease of 10,832 sq. ft. of office/warehouse space
at 1225 Northmeadow Parkway, Suite 120, Roswell, Georgia which is more
particularly described in Exhibit "A" to the Agreement and certain easements,
rights and privileges appurtenant thereto (hereinafter referred to as the
"Existing Space"); and

         WHEREAS, Weeks Realty, L.P. succeeded to the interest of the landlord
under the Agreement and is the Landlord with respect to the Leased Premises; and

         WHEREAS, Tenant desires to exercise its option to lease an additional
5,714 square feet of adjacent space known as 1225 Northmeadow Parkway, Suite 114
(hereinafter the "Additional Space"); and

         WHEREAS, the Agreement will expire by its terms on March 31, 1999 and
Tenant desires to continue to occupy the Leased Premises; and

         WHEREAS, Landlord and Tenant desire to enter into this Second Amendment
in order to provide for said expansion of the Leased Premises and to extend the
term of the Agreement upon terms and conditions mutually acceptable to Landlord
and Tenant;

         NOW, THEREFORE, for and in consideration of Ten Dollars ($10.00) paid
by Landlord and Tenant to one another, and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged by
Landlord and Tenant, Landlord and Tenant amend the Agreement as follows:

         1. Effective December 1, 1997 and continuing until midnight on March
31, 2001, Tenant shall lease an additional 5,714 square feet of space at 1225
Northmeadow Parkway, Suite 114, Roswell, Georgia as shown on the attached
Exhibit "A", which together with the 10,832 of the Existing Space, equals a
total of 16,546 square feet (the Additional Space and the Existing Space shall
be collectively hereinafter referred to as the "Leased Premises" for all
purposes of the Agreement, as amended hereby).

         2. Effective December 1, 1997, Paragraph 3(b) of the Agreement is
hereby amended to provide that Tenant shall pay the Base Rental as set forth
below:

<TABLE>
<CAPTION>
Existing Space (10,832 square feet):
------------------------------------
<S>                                          <C>                        <C>
December 1, 1997 - March 31, 1998            $ 9,631.45/month           $115,577.44/year
April 1, 1998 - March 31, 1999               $ 9,983.49/month           $119,801.92/year
April 1, 1999 - March 31, 2000               $10,362.61/month           $124,351.36/year
April 1, 2000 - March 31, 2001               $10,759.79/month           $129,117.44/year
</TABLE>


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<TABLE>
<CAPTION>
Additional Space (5,714 square feet):
-------------------------------------
<S>                                          <C>                        <C>
December 1, 1997 - March 31, 1998            $ 4,871.19/month           $ 58,454.22/year
April 1, 1998 - March 31, 1999               $ 5,056.89/month           $ 60,682.68/year
April 1, 1999 - March 31, 2000               $ 5,252.19/month           $ 63,025.42/year
April 1, 2000 - March 31, 2001               $ 5,452.11/month           $ 65,425.30/year

<CAPTION>
Total Leased Premises (16,546 square feet):
-------------------------------------------
<S>                                          <C>                        <C>
December 1, 1997 - March 31, 1998            $14,502.64/month           $174,031.66/year
April 1, 1998 - March 31, 1999               $15,040.38/month           $180,484.60/year
April 1, 1999 - March 31, 2000               $15,614.80/month           $187,376.78/year
April 1, 2000 - March 31, 2001               $16,211.90/month           $194,542.74/year
</TABLE>

         which payments shall be due and payable on or before the first day of
each calendar month during the applicable term, together with any other
additional rental as set forth hereunder or as set forth in the Agreement.

         4. Landlord has agreed to construct certain tenant improvements to the
Additional Space as shown on the plans and specifications attached hereto as
Exhibit "A" for a total cost of $36,554.00. Landlord has agreed to contribute
$2.50 per square foot contained in the Additional Space, or the sum of
$14,285.00 toward the cost of the tenant improvements. In addition, Landlord has
agreed to amortize an amount equal to $22,269.00 over the remaining term of the
Lease at a rate of ten (10%) percent per annum, which amount is included in the
Base Rental set out in paragraph 3 above.

         5. Landlord hereby grants to Tenant the right of first refusal to lease
the adjacent space, known as Suite 110, which is currently being leased to
another tenant (the Adjacent Space) upon the terms and conditions contained
herein.

         So long as Tenant is not then in default under the Lease, Landlord will
         notify Tenant when it has made a proposal to lease any portion of the
         Adjacent Space to a third party or the existing tenant and the terms
         and conditions upon which it is willing to lease such space.

         Tenant shall provide written notice to Landlord, as to Tenant's
         decision to lease or not to lease that portion of the Adjacent Space
         within five (5) business days after Landlord's notice to Tenant is
         received. If Tenant does provide such notice to lease the Adjacent
         Space, Landlord and Tenant will execute a lease for the Adjacent Space
         within ten (10) days after Landlord's receipt of Tenant's notice of
         intent to lease on all the same terms as this Lease except for the
         rental terms, and other matters which shall be the same as those
         contained in the proposal. If Tenant does not provide written notice or
         indicates that it will not exercise its right of first refusal, this
         right will expire and Landlord shall have no future obligations to
         Tenant with regard to that portion of the Adjacent Space which was
         subject to such notice.

         This right of first refusal to lease the Adjacent Space is personal to
         Biofield Corp. and may not be assigned in connection with an assignment
         of this Lease or otherwise, except to a successor to Biofield Corp.

         6. Except as expressly modified by this Second Amendment, all
provisions, terms and conditions of the Agreement shall remain in full force and
effect.

         7. In the event a provision of this Second Amendment conflicts with a
provision of the Agreement, the Second Amendment shall supersede and control.

         8. All terms and phrases used herein shall have the same meaning as
assigned to them in the Agreement, unless otherwise defined herein.


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         9.  This Second Amendment shall not be of any legal effect or
consequence unless signed by Landlord and Tenant, and once signed by Landlord
and Tenant it shall be binding upon and inure to the benefit of Landlord,
Tenant, and their respective legal representatives, successors and assigns.

         10. This Second Amendment has been executed and shall be construed
under the laws of the State of Georgia.

         IN WITNESS WHEREOF, the undersigned have caused this Second Amendment
to be executed under seal and delivered as of the day and year first above
written.

                                             LANDLORD:

Signed, sealed and delivered                 WEEKS REALTY, L.P.
in the presence of:                          a Georgia limited partnership

                                             By: Weeks GP Holdings, Inc.
------------------------------                   a Georgia corporation,
Witness                                          its sole general partner


-----------------------------
Notary Public            By:
                            -------------------------
                                             Name:
                                                  ----------------------
                                                  Its:
                                                      --------------------------




                                             TENANT:

Signed, sealed and delivered                 BIOFIELD CORP.
in the presence of:

                                             By:
-----------------------------                   ------------------------
Witness                                      Name:
                                                  ----------------------
                                              Its:
                                                  ------------------------------


----------------------------
Notary Public

                                             ATTEST:

                                             By:
                                                ------------------------
                                             Name:
                                                  ----------------------
                                             Its:
                                                 -----------------------

                                                    [Corporate Seal]


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