12. The Contractor shall keep full, accurate and careful account of all supplies and materials acquired by it for use under this contract, and shall also keep in separate accounts a full, accurate and careful record of all labor employed in, about or in connection with such work under this contract, and the Owner shall have the right to be exercised at its discretion, at any time or times during the progress of said work and until full payment hereunder, by its duly accredited agent to inspect the books, papers, records and accounts of the Contractor with respect to such supplies, materials and time, and to inspect such supplies and materials and check up such supplies and materials.

13. No certificate given or payment made under this contract, except the final certificate or final payment, shall be conclusive evidence of the performance of this contract, either wholly or in part, and no payment except the final payment shall be construed to be an acceptance of defective work or improper materials.

14. In case the Architect and the Contractor fail to agree in relation to matters respecting payment, or the true construction or meaning of the plans or specifications, or as to defective work or materials as hereinbefore mentioned, or as to whether the Contractor is entitled to the final certificate of performance, or protection of or damage to work, or should any dispute arise in respect of any extension of time, such questions shall be determined by arbitration. The Contractor agrees to prosecute the work with promptness and diligence during the arbitration proceedings. The parties may agree upon one arbitrator; otherwise there shall be three, one named in writing by each party and the third chosen by these two arbitrators, no one of whom shall have been or shall be connected with the work covered by this agreement. If said two arbitrators fail to select a third within five days, he shall be chosen by the president of the New York Society of Architects. Should the party demanding arbitration fail to name an arbitrator within three days of its demand, its right to arbitration shall lapse. Should the other party fail to choose an arbitrator within such three days, then the party demanding arbitration shall deliver a notice in writing to the party so failing, and requesting said party to choose an arbitrator, as provided in this paragraph, and if said party shall fail to choose such arbitrator and to notify the other in writing of such selection within twenty-four hours after the receipt of such notice, then the Architect shall appoint one in its stead with the same power as though he had been appointed by said party. The arbitrators shall act with promptness. The decision of any two shall be binding on all parties to the dispute. The expense of such arbitration shall be borne by the party against whom the award is made.

15. (a) The Contractor agrees that its work hereunder shall be substantially completed according to the plans and specification on............. If the Contractor be delayed in the completion of the work by any act or neglect of the Owner on the Architect, or of any employee of either, or by any other Contractor employed by the Owner, or by changes ordered in the work, or by weather conditions, or by strikes, lockouts, fire, unusual delay by common carriers, unavoidable casualties or any causes beyond the Contractor's control, or by delay authorized by the Architect pending arbitration, or by any cause which the Architect shall decide to justify the delay, then the time of completion shall be extended for a period equivalent to the time lost, or additional time properly required on account of and by reason of any or all of the causes aforesaid. Provided, however, that if the Contractor shall be delayed for a period of three months through any act or fault of the Owner, then the contractor may stop work and terminate this contract, and recover from the owner payment for all work executed and materials delivered, including said Contractor's profit, overhead charge prorated to the time of such termination, and any loss sustained upon any plant or material, and damages.

(b) In the event that said building is wholly, or partially but substantially, destroyed while in the course of construction by fire, lightning, earthquake, cyclone or tornado, flood, act of God or of the elements, or by any other causes beyond the control of the Contractor, the time herein fixed for the completion of the work or any portion thereof shall be extended for a period equivalent to the time requisite and necessary to put the works in the stage of progress in which they were before such destruction.

(c) If the Owner shall decide not to rebuild the building or to repair any such partial destruction, it shall have the right to abandon the further prosecution of the work, on condition that it pay to the Contractor the total cost to the Contractor of performance to the date of due notice to the Contractor of such abandonment, including the said overhead charge prorated to such date, the expense of removal of the Contractor's apparatus and works, the cost of all materials delivered on the premises, or other place of storage of such materials, the cost or price of all materials or structures specially made for the said building, and any and all loss, however sustained, which the Contractor may sustain by reason of orders for materials, structures or other commodities contracted for for use in said building, plus ten (10%) per cent. of the Contractor's total cost.

(d) The Owner shall, within ten days after the happening of any of the contingencies mentioned in the foregoing subdivisions (b) and (c) of this paragraph, exercise its election as to whether it shall abandon the further prosecution of the work, or shall rebuild the building. In the event of its failure to decide and notify the Contractor within said period, it shall be deemed to have decided to abandon and to have abandoned the further prosecution of the work, as mentioned in subdivision (c) of this paragraph.