258 THE LAW AFFECTING ENGINEEES 



26. Access to site. In the execution of the work, no person other than 

 the contractor, or his duly appointed superintendent, sub-contractors and 

 workmen, shall be allowed to do work on the site, except by the special 

 permission, in writing, of the engineer, but access to the works at all 

 times shall be accorded to the engineer and his representatives, and other 

 officials or representatives of the purchasers. 



[NOTE. As to the advisability of preventing strangers having access to the 

 site of the works, see Chap. V., 12.] 



27. Materials '{brought on to the site. The contractor shall provide all 

 materials, labour, haulage power, tools, tackle, and plant of every descrip- 

 tion, necessary to execute and complete the works in an efficient and 

 satisfactory manner. All such materials, plant, tools, and tackle (except 

 as provided by Clause 24 with regard to instruments and apparatus for 

 testing empty drums and packing cases), brought to and delivered upon 

 the site for the purpose of the work, shall, from the time of their being 

 so brought, vest in and be the property of the purchasers until the com- 

 pletion of the contract, when the property in any surplus materials, and 

 in the plant and tools, shall revert to the contractor, unless there shall 

 be due, owing to, or accruing, or to accrue, from the contractor to the 

 purchasers, any money or moneys under, or in respect of or by reason of 

 this contract, in which case the purchasers shall be at liberty to sell and 

 dispose of such materials, plant and tools as they shall think fit, and to 

 apply the proceeds in or towards the satisfaction of such money or moneys 

 so due, owing or accruing, or to accrue to them as aforesaid. 



If application be made to the engineer by the contractor, he may at 

 any time permit the removal of such machinery, plant, tools, and tackle 

 as may not be required for the execution of work under this contract, or 

 which may be required by the contractor for uses elsewhere. 



27A*. Materials to be described. The contractor must produce vouchers 

 proving all materials to be genuine, and of the nature described in the 

 specification, when called upon to do so by the engineer. 



28. Engineer's supervision. All the works are to be carried out under 

 the direction, control, and to the entire satisfaction in every respect of 

 the engineer; but the contractor shall be responsible for the accuracy of 

 his work, and no plea as to the acts or general supervision of the 

 engineer otherwise than instructions given by him in writing will be 

 admitted in justification of any errors of construction or fixing. 



29. Engineer's decisions. In respect of all matters which are left to the 

 decision or certificate of the engineer, the engineer shall, if required so to 

 do by the contractor, give in writing a decision thereon, and his reasons 

 for such decision, or if he shall withhold any certificate then his 

 reasons for so doing. All decisions of the engineer shall be subject to 

 the right of arbitration reserved by these conditions. 



[NOTE. As to whether an engineer is bound to give reasons if the contract 

 does not specially so provide, see Chap. XIV., 6.] 



30. Contractor's superintendent and workmen. The contractor shall 

 constantly employ at least one competent superintendent to superintend 

 the erection of the plant and the carrying out of the works. The said 



