**Exhibit 10(a)**

SECONDAMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT,

AND REAFFIRMATION OF GUARANTIES

This SECOND AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT ANDREAFFIRMATION OF GUARANTIES, dated as of March 15, 2007 (the “Second Amendment”),is entered into by and between QUIXOTE CORPORATION, a Delaware corporation (the“Borrower”), whose address is Thirty Five East Wacker Drive, Chicago, Illinois60601, and QUIXOTE TRANSPORTATION SAFETY, INC., TRANSAFE CORPORATION,ENERGY ABSORPTION SYSTEMS, INC., ENERGY ABSORPTION SYSTEMS (AL) LLC, SURFACESYSTEMS, INC., NU-METRICS, INC., HIGHWAY INFORMATION SYSTEMS, INC., U.S.TRAFFIC CORPORATION (formerly known as Green Light Acquisition Corporation),PEEK TRAFFIC CORPORATION, (formerly known as Vision Acquisition Corporation),as Subsidiary Guarantors, eachbeing referred to herein as a “Guarantor” and collectively referred to hereinas the “Guarantors”), and LASALLE BANK NATIONAL ASSOCIATION, a national bankingassociation (the “Bank”), whose address is 135 South LaSalle Street, Chicago,Illinois 60603.

R E C I T A L S:

A.            TheBorrower and the Bank entered into that certain Amended and Restated CreditAgreement, dated as of April 20, 2005, as amended by a First Amendment, datedas of December 1, 2006, and as modified and amended (collectively, the “LoanAgreement”), pursuant to which Loan Agreement the Bank has made a RevolvingLoan to the Borrower evidenced by that certain Revolving Note, dated as ofApril 20, 2005, in the maximum principal amount of $30,000,000, executed byBorrower and made payable to the order of the Bank.

B.            Inconnection with the Loan Agreement, the Guarantors executed and delivered tothe Bank that certain Guaranty, dated as of May 16, 2003 in favor of the Bank,as amended by that Reaffirmation and Amendment of Subsidiary Guaranty, dated asof April 20, 2005.

C.            Atthe present time the Borrower and the Guarantors request and the Bank isagreeable to (i) the extension of the Revolving Loan Termination Date toFebruary 1, 2009; and (ii) the modification of the pricing grid based onBorrower’s Senior Leverage Ratio as set forth in Section 2.13(D)(ii), pursuantto the terms and conditions hereinafter set forth.

NOW THEREFORE, in consideration of the premises andother good and valuable consideration, the receipt and adequacy of which arehereby acknowledged, the Borrower, the Guarantors and the Bank hereby agree asfollows:

A G R E E M E N T S:

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1.             RECITALS.  The foregoing Recitals are hereby made a partof this Second Amendment.

2.             DEFINITIONS.  Capitalized words and phrases used hereinwithout definition shall have the respective meanings ascribed to such wordsand phrases in the Loan Agreement.

3.             AMENDMENTSTO THE LOAN AGREEMENT.

3.1           Section1.1 of the Loan Agreement.  Thedefinition of “Revolving Loan Termination Date” in Section 1.1 of the LoanAgreement is hereby amended to delete “February 1, 2008” and insert “February1, 2009”.

3.2           Section1.1 of the Loan Agreement. References to “Section 2.14(D)(ii)” in the definitions of “Applicable ABRMargin”; “Applicable Eurodollar Margin” and “Applicable Commitment FeePercentage” are amended and restated to read “Section 2.13(D)(ii).”

3.3           Section 2.13 of Loan Agreement.  Section 2.13(d)(ii) is hereby amended bydeleting the existing pricing grid set forth herein and inserting the followingpricing grid in lieu thereof:
| **Level** | ** ** | **Senior Leverage  Ratio** | ** ** | **Eurodollar  Margin/L/C Fee  Percentage** | ** ** | **ABR  Margin** | ** ** | **Commitment  Fee  Percentage** | ** ** |
|-----------|------------|---------------------------------|------------|-------------------------------------------------|------------|-----------------|------------|---------------------------------|------------|
| VI        |       | >3.00                        |       | 2.50                                            | %          | 0               | %          | 0.375                           | %          |
| V         |       | >2.50  BUT<3.00           |       | 2.25                                            | %          | 0               | %          | 0.375                           | %          |
| IV        |       | >2.00  BUT<2.50           |       | 2.00                                            | %          | 0               | %          | 0.250                           | %          |
| III       |       | >1.50  BUT<2.00           |       | 1.75                                            | %          | 0               | %          | 0.250                           | %          |
| II        |       | >1.00  BUT<1.50           |       | 1.50                                            | %          | 0               | %          | 0.250                           | %          |
| I         |       | <1.00                        |       | 1.25                                            | %          | 0               | %          | 0.250                           | %          |

 

3.4           RevolvingNote.  All references in the LoanAgreement to the Revolving Note in the form of “Exhibit A” to the LoanAgreement shall be deemed to be references to the Replacement Revolving Note inthe form of Exhibit A attached hereto and made a part hereof (the “ReplacementRevolving Note”).

4.             REAFFIRMATIONOF GUARANTIES.  Each of theGuarantors hereby expressly (a) consents to the execution by the Borrower andthe Bank of this Second Amendment, (b) acknowledges that the “Guaranteed Debt”(as defined in each of the Guaranties) includes all of the obligations andliabilities owing from the Borrower to the Bank, including, but not limited to,the obligations and liabilities of the Borrower to the Bank under and pursuantto the Loan Agreement, as amended from time to time, and as evidenced by theRevolving Note, as modified, extended and/or replaced from time to time, (c)reaffirms, assumes and binds themselves in all respects to all of theobligations, liabilities, duties, covenants, terms and conditions that arecontained in their respective Guaranty, (d) agrees that all such obligationsand liabilities under their respective Guaranty shall continue in full forceand effect and shall not be 

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discharged, limited, impaired or affected in any manner whatsoever, and(e) represents and warrants that each of the representations and warrantiesmade by such Guarantor in any of the documents executed in connection with theLoans remain true and correct as of the date hereof.

5.             REPRESENTATIONSAND WARRANTIES.  To induce the Bankto enter into this Second Amendment, the Borrower hereby certifies, representsand warrants to the Bank that:

5.1           Organization.  The Borrower is a corporation duly organized,existing and in good standing under the laws of the State of Delaware with fulland adequate corporate power to carry on and conduct its business as presentlyconducted.  The Borrower is duly licensedor qualified in all foreign jurisdictions wherein the nature of its activitiesrequire such qualification or licensing. The Articles of Incorporation andBylaws, Borrowing Resolutions and Incumbency Certificate of the Borrower havenot been changed or amended since the most recent date that certified copiesthereof were delivered to the Bank.  TheBorrower’s state issued organizational identification number is ________ [state“None” if the Borrower’s state of organization does not issue such anumber].  The exact legal name of theBorrower is as set forth in the preamble of this Second Amendment, and theBorrower currently does not conduct, nor has it during the last five (5) yearsconducted, business under any other name or trade name.  The Borrower will not change its name, itsorganizational identification number, if it has one, its type of organization,its jurisdiction of organization or other legal structure.

5.2           Authorization.  The Borrower is duly authorized to executeand deliver this Second Amendment and is and will continue to be dulyauthorized to borrow monies under the Loan Agreement, as amended hereby, and toperform its obligations under the Loan Agreement, as amended hereby.

5.3           NoConflicts.  The execution and deliveryof this Second Amendment and the performance by the Borrower of its obligationsunder the Loan Agreement, as amended hereby, do not and will not conflict withany provision of law or of the articles of incorporation or bylaws of theBorrower or of any agreement binding upon the Borrower.

5.4           Validityand Binding Effect.  The LoanAgreement, as amended hereby, is a legal, valid and binding obligation of theBorrower, enforceable against the Borrower in accordance with its terms, exceptas enforceability may be limited by bankruptcy, insolvency or other similarlaws of general application affecting the enforcement of creditors’ rights orby general principles of equity limiting the availability of equitableremedies.

5.5           Compliancewith Loan Agreement.  Therepresentation and warranties set forth in Section VI of the Loan Agreement, asamended hereby, are true and correct with the same effect as if suchrepresentations and warranties had been made on the date hereof, with theexception that all references to the financial statements shall mean thefinancial statements most recently delivered to the Bank and except for suchchanges as are specifically permitted under the Loan Agreement.  In addition, the Borrower has complied withand is in compliance with all of the covenants set forth in the Loan Agreement,as amended hereby, including, but not limited to, those set forth in SectionVII thereof.

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5.6           NoEvent of Default.  As of the datehereof, no Event of Default under Section VIII of the Loan Agreement, as amendedhereby, or event or condition which, with the giving of notice or the passageof time, or both, would constitute an Event of Default, has occurred or iscontinuing.

5.7           NoSubordinated Debt Default.  As of thedate hereof, no default under any of the documents evidencing or securing anyof the Junior Debt, or event or condition which, with the giving of notice orthe passage of time, or both, would constitute a default under any of thedocuments evidencing or securing any of the Subordinated Debt, has occurred oris continuing.

6.             CONDITIONSPRECEDENT.  This Second Amendmentshall become effective as of the date above first written after receipt by theBank of the following documents:

6.1           SecondAmendment.  This Second Amendmentexecuted by the Borrower, the Guarantors, and the Bank.

6.2           ReplacementRevolving Note.  A ReplacementRevolving Note, dated as of March 15, 2007, in the maximum principal amount of$30,000,000, executed by Borrower and made payable to the order of the Bank inthe form of Exhibit A attached hereto.

6.3           Resolutions.  A certified copy of Resolutions of the boardof directors of Borrower authorizing the execution, delivery and performance ofthis Second Amendment and related loan documents.

6.4           OtherDocuments.  Such other documents,certificates and/or opinions of counsel as the Bank may request.

7.             GENERAL.

7.1           GoverningLaw; Severability.  This SecondAmendment shall be construed in accordance with and governed by the laws ofIllinois.  Wherever possible eachprovision of the Loan Agreement and this Second Amendment shall be interpretedin such manner as to be effective and valid under applicable law, but if anyprovision of the Loan Agreement and this Second Amendment shall be prohibitedby or invalid under such law, such provision shall be ineffective to the extentof such prohibition or invalidity, without invalidating the remainder of suchprovision or the remaining provisions of the Loan Agreement and this SecondAmendment.

7.2           Successorsand Assigns.  This Second Amendment shallbe binding upon the Borrower, the Guarantors, and the Bank and their respectivesuccessors and assigns, and shall inure to the benefit of the Borrower, theGuarantors, and the Bank and the successors and assigns of the Bank.

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7.3           ContinuingForce and Effect of Loan Documents and Guaranty.  Except as specifically modified or amended bythe terms of this Second Amendment, all other terms and provisions of the LoanAgreement and the other Loan Documents are incorporated by reference herein,and in all respects, shall continue in full force and effect.  The Borrower, by execution of this SecondAmendment, hereby reaffirms, assumes and binds itself to all of theobligations, duties, rights, covenants, terms and conditions that are containedin the Loan Agreement and the other Loan Documents.  Each of the Guarantors, by execution of thisSecond Amendment, hereby reaffirms, assumes and binds itself to all of theobligations, duties, rights, covenants, terms and conditions that are containedin Guaranty.

7.4           FinancingStatements.  The Borrower herebyirrevocably authorizes the Bank at any time and from time to time to file inany jurisdiction any initial UCC financing statements and/or amendments theretothat (a) describe the Collateral, and (b) contain any other informationrequired by part 5 of Article 9 of the UCC for the sufficiency or filing officeacceptance of any financing statement or amendment.

7.5           Referencesto Loan Agreement.  Each reference inthe Loan Agreement to “this Agreement”, “hereunder”, “hereof”, or words of likeimport, and each reference to the Loan Agreement in any and all instruments ordocuments delivered in connection therewith, shall be deemed to refer to theLoan Agreement, as amended hereby.

7.6           Expenses.  The Borrower shall pay all costs and expensesin connection with the preparation of this Second Amendment and other relatedloan documents, including, without limitation, reasonable attorneys’ fees andtime charges of attorneys who may be employees of the Bank or any affiliate orparent of the Bank.  The Borrower shallpay any and all stamp and other taxes, UCC search fees, filing fees and othercosts and expenses in connection with the execution and delivery of this SecondAmendment and the other instruments and documents to be delivered hereunder,and agrees to save the Bank harmless from and against any and all liabilitieswith respect to or resulting from any delay in paying or omission to pay suchcosts and expenses.

7.7           Counterparts.  This Second Amendment may be executed in any numberof counterparts, all of which shall constitute one and the same agreement.

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IN WITNESS WHEREOF, the parties hereto have executedthis Second Amendment to the Amended and Restated Credit Agreement andReaffirmation of Guaranties as of the date first above written.
|        | QUIXOTE CORPORATION                 |
|--------|-------------------------------------|
|   | a Delaware corporation, as Borrower |
|   |                                |   |
|   |                                |   |
|   | By:                                 | /s/ Daniel P. Gorey |
|   | Name:                               | Daniel P. Gorey |
|   | Title:                              | Vice President, Chief Financial Officer |
|   |                                | and Treasurer |
|   |                                |   |
|   |                                |   |
|   | QUIXOTE TRANSPORTATION SAFETY, INC. |
|   | TRANSAFE CORPORATION                |
|   | ENERGY ABSORPTION SYSTEMS, INC.     |
|   | ENERGY ABSORPTION SYSTEMS (AL) LLC  |
|   | SURFACE SYSTEMS, INC.               |
|   | NU-METRICS, INC.                    |
|   | HIGHWAY INFORMATION SYSTEMS, INC.   |
|   | U.S. TRAFFIC CORPORATION            |
|   | PEEK TRAFFIC CORPORATION,           |
|   |                                |   |
|   |                                |   |
|   | Name:                               | /s/ Daniel P. Gorey |
|   | Title:                              | Vice President and  Treasurer |
|   |                                |   |
|   |                                |   |
|   | LASALLE BANK NATIONAL  ASSOCIATION, |
|   | a national banking  association     |
|   |                                |   |
|   |                                |   |
|   | By:                                 | /s/ Lora Backofen |
|   | Name:                               | Lora Backofen |
|   | Title:                              | Senior Vice President |

 

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REVOLVING LOAN NOTE
| $30,000,000 | Chicago, Illinois |
|-------------|-------------------|
|        | March 15, 2007    |

 

FOR VALUE RECEIVED, the undersigned, QUIXOTECORPORATION, a Delaware corporation (the “Borrower”), promises to pay to theorder of LaSalle Bank National Association and its registered assigns (the “Lender”),on February 1, 2009, the principal sum of Thirty Million Dollars, or, if less,the aggregate unpaid principal amount of all Loans made by the Lender to theBorrower from time to time pursuant to that certain Amended and Restated CreditAgreement, dated as of April 20, 2005, between the Borrower and Lender asamended by a First Amendment, dated as of December 1, 2006, and a SecondAmendment, dated as of the date hereof, (together with all amendments, if any,from time to time made thereto, the “Credit Agreement”).

The Borrower agrees to pay interest on the principalhereof remaining from time to time unpaid in accordance with Section 2.13 ofthe Credit Agreement.

All payments of principal of and interest on thisNote shall be payable in lawful currency of the United States of America at theAgent’s office at 135 South LaSalle Street, Chicago, Illinois 60603, inimmediately available funds.

This Note evidences indebtedness incurred under, andis subject to the terms and provisions of, the Credit Agreement, to whichreference is made for a statement of those terms and provisions.  Should the indebtedness represented by thisNote or any part hereof be collected at law or in equity or in bankruptcy,receivership, or other court proceedings, or this Note be placed in the handsof attorneys for collection after maturity (by declaration or otherwise), theundersigned agrees to pay, in addition to principal and interest due andpayable hereon, reasonable attorneys’ and collection fees.

This Revolving Note constitutes a renewal andrestatement of, and replacement and substitution for, that certain RevolvingNote, dated as of April 1, 2005 in the maximum principal amount of ThirtyMillion and 00/100 Dollars ($30,000,000.00), executed by the Borrower and madepayable to the order of the Bank (the “Prior Note”).  The indebtedness evidenced by the Prior Noteis continuing indebtedness evidenced hereby, and nothing herein shall be deemedto constitute a payment, settlement or novation of the Prior Note, or to releaseor otherwise adversely affect any lien, mortgage or security interest securingsuch indebtedness or any rights of the Bank against any guarantor, surety orother party primarily or secondarily liable for such indebtedness.
|        | QUIXOTE CORPORATION |
|--------|---------------------|
|   |                |   |
|   |                |   |
|   | By:                 | /s/ Daniel P. Gorey |
|   | Name:               | Daniel P. Gorey |
|   | Title:              | Vice President, Chief Financial |
|   |                | Officer and Treasurer |
|   |                |   |

 

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