all samples shall be supplied by the contractor at his own cost if the supply thereof is clearly intended by of provided for in the contract， but if not， then at the cost of the employer.
the cost of making any test shall be borne by the contractor if such test is clearly intended by of provided for in the contract and， in the cases only of a test under load or of a test to ascertain whether the design of any finished or partially finished work is appropriate for the purposes which it was intended to fulfil， is particularized in the contract in sufficient detail to enable the contractor to price of allow for the same in his tender：
if any test is ordered by the employer which is either：
（a）not so intended by or provided for； or
（b）（in the cases above mentioned） is not so particularized；or
（c）though so intended or provided for is ordered by the employer to be carried out by an independent person at any place other than the site or the place of manufacture or fabrication of the materials tested ；then the cost of such test shall be borne by the contractor， if the test shows the workmanship or materials not to be in accordance with the provisions of the contract.19 inspection of operations
the employer and any person authorized by him shall at all times have access to the works and to all workshops and places where work is being prepared or from where materials， manufactured articles or machinery are being obtained for the works and the contractor shall afford every facility for and every assistance on or in obtaining the right to such access.
no work shall be covered up or put out of view without the approval of the employer and the contractor shall afford full opportunity for the employer to examine and measure any work which is about to be covered up or put out of view and to examine foundations before permanent work is placed there on. the contractor shall give due notice to the employer whenever any such work or foundations is or are ready or about to be ready for examination and the employer shall， without unreasonable delay， unless he considers it unnecessary and advises the contractor accordingly， attend for the purpose of examining and measuring such work or of examining such foundations.20 removal of improper work and materials
the employer shall during the progress of the works have power to order in writing from time to time，
（a）the removal from the site， within such time or times as may be specified in the order， of any material which， in the opinion of the employer， are not in accordance with the contract；