ON THE MKCHANICAL PROPERTIES OF STEEL. 



169 



TKANSTEESE STKAIN. 



Exp. IV. — Bar of Steel from Messrs. John Brown & Co., Sheffield. Dimen- 

 sion of bar -98 inch square. Length between supports 4 feet 6 inches. 

 Mark on bar, "B 4." 



Results of Exp. IV. 



Here the weight {tu) at the limit of elasticity is 960 lbs., and the corre- 

 ponding deflection (I) is 1^318. 



By formula (6). — The mean value of the deflection for unity of pressure 

 and section (D^) = -0012581. 



By formula (7). — The mean value of the modulus of elasticity (E) 

 = 29,463,000. 



By formula (2). — The modulus of elasticity (E) corresponding to 112 lbs. 

 pressure = 29,370,000. 



By formula (8).— Work of deflection (U) up to the limit of elasticity 

 = 52-720. 



By formula (9).— Work of deflection (?f)for unity of section = 54-893. 



By formula (12).— Value of C, the unit of working strength = 6-134 

 tons. 



