Failure by Contractor to comply with Employer’s instructions. If the Contractor after receipt of written notice from the Employer requiring compliance within ten days fails to comply with such further the Employer may employ and pay other persons to execute any such work whatsoever that may be necessary to give effect thereto, and all costs incurred in connection therewith shall be recoverable from the Contractor by the Employer or may be deducted by him from any moneys due to the Contractor.