SPECIFICA TIONS. 303 



the expense of mill and laboratory tests shall be paid by the con- 

 tractor and must be included in the price bid for this water- 

 tower. 



From each lot of materials offered, one or more samples 

 will be selected by the inspector for testing, and all pieces intended 

 to be used in the work shall have the number representing the 

 melt from which this material has been rolled clearly stamped 

 upon them, and the absence of such numbers shall be deemed 

 sufficient cause for rejection. 



Each melt of steel must be represented by test, and when 

 required, tests shall be made of the different sizes and shapes 

 from the same melt. Chemical analysis of borings taken from 

 each shall be made to determine the amount of phosphorus and 

 sulphur in the material proposed to be furnished. 



Allowance for variation in weight shall be made by the in- 

 spector in accordance with the standard adopted by the American 

 Steel Manufacturers' Association. 



Manufacturers shall afford inspectors the usual facilities for 

 the examination of materials, which to pass a surface inspection 

 must appear to be a good merchantable product, sound and 

 well finished. 



Materials that have been warped or buckled shall be rejected. 



If, for lack of transportation or other cause, delay in shipment 

 occurs, the material must be safely stored and protected. 



After leaving the mill, the right is reserved to appoint in- 

 spectors both at the shop and in the field to approve materials 

 and constructive methods, but the wages of such employes shall 

 not be assessed against the contractor. 



STRESSES. 



The thickness of the plates composing the cylinder and the 

 bottom shall be such as to sustain the stresses produced by their 

 weight and contents, with a factor of safety of at least four (4) 



