302 TOWERS AND TANK'S FOR WATER-WORKS. 



as determined from a standard test-piece cut from the finished 

 material. 



Cold and quench bends 180 degrees flat on itself without 

 fracture on outside of bent portion. 



Broken samples must show a silky fracture of uniform color. 



Punched rivet-holes, pitched two diameters from a sheared 

 edge, must stand drifting without cracking the material until 

 the diameter is one-third greater than the original hole. 



The ultimate strength for structural steel shall be the same as 

 specified for plate metal. 



Finished bars shall be free from injurious seams, flaws, or 

 cracks and shall have a workmanlike finish. 



Test-pieces of full-size cross-section shall bend, either hot or 

 cold, 1 80 degrees around a two-inch pin without cracking on 

 the convex surface. 



The ultimate strength of rod and rivet steel shall be from 

 48,000 to 58,000 Ibs. per square inch. 



Test-pLa:3 shall bend 1 80 degrees flat on themselves without 

 fracture on outside of bent portions. 



The rivets to be used in this structure shall be the output of a 

 manufactory having a reputation for a superior product, and 

 the manufacturer's test of rods shall be accepted as sufficient 

 by the engineer, but rivets taken at random from any shipment 

 must successfully withstand any usual and reasonable test that 

 may be ordered by the engineer prior to their use. 



All rods requiring threading shall be properly "upset." and 

 rods, nuts, turnbuckles, or clevises must be threaded to the U. S 

 standard. 



Pins shall be of material of superior quality and shall be 

 accurately turned. 



INSPECT i ox. 



An expert inspector shall b<- sele< ted by the engineer for the 

 purpose of testing the materials proposed to be furnished, and 



