110 



REPORT 1869. 



TEANSTEESE STEAIN. 



Exp. IV. (January 1868). — Bar of Steel from the Barrow Haematite Steel 

 Company. Dimension of bar 1-071 inch square. Length between 

 supports 4 feet 6 inches. Mark on bar, " H 1 + ." 



Results of Exp. IV. 



Here the weight (w) at the limit of elasticity is 660 lbs., and the corre- 

 sponding deflection {K) is '771. 



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

 and section (Dj) = -001383. 



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

 = 28,460,000. 



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

 pressure = 31,740,000. 



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

 = 21-20. 



By formula (9). — Work of deflection (h) for unity of section = 18^48. 



By formula (12). — Value of C, the unit of working strength = 3^228 tons. 



