104 



REPORT — 1853. 



On comparing the resisting powers of the iron from this melting 

 with that of the last, it will be found that a sudden and rapid de- 

 cline of nearly one-half the strength has taken place. Referring 

 to the drawing of this iron, it will be observed that all the four 

 corners have become silvered with a fine white frosted surface, 

 which fully accounts for the brittle nature of the bars, and the 

 consequent loss of adhesion in those parts furthest from the 

 neutral axis ; and in which, when exposed to a transverse strain, 

 is the principal strength of the bar. Colour a light gray, sur- 

 rounded with four triangles of white silvery iron at each corner, 

 as seen in the figure. 



Results reduced to those of bars TOO in. square. 



Experiment 1, bar 4 ft. 6 in. between 

 supports 



Experiment 2, bar 4 ft. C in. between 

 sujiports 



Experiment 3, bar 4 ft. 6 in. between 

 supports 



Mean 



Specific 

 gravity. 



7-248 



r-248 



Breaking 



weiglit 



(b). 



399-6 

 376-9 

 336-9 



3711 



Ultimate 

 deflection 



0-64 

 0-64 

 0-65 



0-643 



Product b X 



d, or power 



of resisting 



impact 



255-7 

 241-2 

 218-8 



238-6 



