ON THE MECHANICAL PROPERTIES OF STEEL. 



241 



Exp. XL.— Bar of Steel from Messrs. Turton & Sons, Sheffield. Elon- 

 gations taken on 8 inches length. Mark on bar, "E." Diameter 

 of specimen '743 inch. Area -4335 square inch. Reduced diameter 

 after fracture -737 inch. Area '4266 square inch. 



Breaking strain per 

 square inch of section. 



lbs. 



102915 



tons 



45-94 



Per unit of length. 



Elongation 



•0006 

 •0018 

 •0031 

 •0062 

 •0093 

 •0106 

 •0143 

 •0181 



Permanent 

 set. 



•0143 



Eemarkg. 



Specimen of steel 

 used in the ma- 

 nufacture of ma- 

 chinery. 



Broke in neck. 



Results. — Here the breaking strain (P^) per square inch of section is 

 102,915 lbs., or 45-94 tons ; and the corresponding elongation (l^) per unit 

 of length is •0181. By formula (13). — The work (m) expended in produ- 

 cing rupture = 929. 



Exp. XLI.— Bar of Steel from Messrs. Turton & Sons, Sheffield. Elon- 

 gations taken on 8 inches length. Mark on bar, " F." Diameter 

 of specimen -743 inch. Area ^4335 square inch. Eedueed diameter 

 after fracture ^738 inch. Area ^4277 square inch. 



Results. — Here the breaking strain (PJ per square inch of section is 

 102,567 lbs., or 45-79 tons ; and the corresponding elongation (l^) per unit 

 of length is -0206. By formula (13). — The work («) expended in producing 

 rupture = 1056. 



1867. 8 



